\documentclass[journal]{rmaa}

%\usepackage{paralist}
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\title{The San Pedro M\'artir Planetary Nebula Kinematic\\ Catalogue: Extragalactic Planetary Nebulae\altaffilmark{1}} 

\author{
M.~G. Richer,\altaffilmark{2} 
J.~A. L\'opez,\altaffilmark{2}
E. D\'iaz-M\'endez,\altaffilmark{3}
H. Riesgo,\altaffilmark{2}
S.-H. B\'aez,\altaffilmark{4}
Ma.-T. Garc\'ia-D\'iaz,\altaffilmark{2}\\
J. Meaburn,\altaffilmark{5}
D.~M. Clark,\altaffilmark{2} 
R.~M. Calder\'on Olvera,\altaffilmark{6}
G. L\'opez Soto,\altaffilmark{6}
and  O. Toledano Rebolo\altaffilmark{7}}

\altaffiltext{1}{Based on observations obtained at the Observatorio Astron\'omico Nacional at San Pedro M\'artir, Baja California, Mexico.}
\altaffiltext{2}{Instituto de Astronom\'ia, Universidad Nacional Aut\'o\-noma de M\'exico, Mexico.}
\altaffiltext{3}{Texas Christian University, Fort Worth, Texas, USA.}
\altaffiltext{4}{Facultad de F\'isica e Inteligencia Artificial, Universidad Veracruzana, Mexico.}
\altaffiltext{5}{Jodrell Bank Observatory, University of Manchester, UK.}
\altaffiltext{6}{Universidad Nacional Aut\'onoma de M\'exico, Mexico.}
\altaffiltext{7}{Instituto de Ciencias F\'isicas, Universidad Nacional Aut\'onoma de M\'exico, Mexico.}


\shortauthor{Richer et al.}

\shorttitle{SPM PN Kinematic Catalogue: Extragalactic Data}


\fulladdresses{
\item Sol-Haret B\'aez: Facultad de F\'isica e Inteligencia Artificial, Universidad Veracruzana, Circuito G. Aguirre Beltr\'an s/n, 
Zona Universitaria, Xalapa, Veracruz, Mexico (solharet@hotmail.com).
\item Roxana Marisol Calder\'on Olvera, Giovanni L\'opez Soto:  Universidad Nacional Aut\'oma de M\'exico, Ciudad Universitaria, 
04510 M\'exico, D.F., Mexico  (roxanama@msn.com, blackhole\_mx@yahoo.com.mx).
\item David M. Clark, Mar\'ia-Teresa Garc\'ia-D\'iaz, Jos\'e Alberto L\'opez, Michael G. Richer, Hortensia Riesgo: Instituto de 
Astronom\'ia, Universidad Nacional Aut\'onoma de M\'exico, Apdo. Postal 877, 22830,  Ensenada, B.~C., Mexico 
(tere, jal, richer, hriesgo@astrosmo.unam.mx).
\item Enrique D\'iaz-M\'endez: Dept. of Physics and Astronomy, Texas Christian University, Fort Worth, Texas, US.  76109 (e.d.mendez@tcu.edu).
\item John Meaburn: Jodrell Bank Observatory, Dept. of Physics \& Astronomy, University of Manchester, Macclesfield, Cheshire 
SK11 9DL, UK (jm@ast.man.ac.uk).
\item Oswaldo Toledano Rebolo: Instituto de Ciencias F\'isicas, Universidad Nacional Aut\'onoma de M\'exico, Av. Universidad s/n, 
62210, Cuernavaca, Morelos, Mexico (oswaldotoledano@hotmail.com).}


\listofauthors{M.~G.~Richer, J.~A.~L\'opez, E.~D\'iaz-M\'endez, H.~Riesgo, S.-H.~B\'aez, Ma.~T.~Garc\'ia-D\'iaz, J.~Meaburn, 
D.~M. Clark, R.~M.~Calder\'on~Olvera, G.~L\'opez~Soto, \& O.~Toledano~Rebolo}

\indexauthor{Richer, M.~G.}
\indexauthor{L\'opez, J.~A.}
\indexauthor{D\'iaz-M\'endez, E.}
\indexauthor{Riesgo, H.}
\indexauthor{B\'aez, S.-H.}
\indexauthor{Garc\'ia-D\'iaz, Ma.~T.}
\indexauthor{Meaburn, J.}
\indexauthor{Clark, D.~M.}
\indexauthor{Calder\'on Olvera, R.~M.}
\indexauthor{L\'opez Soto, G.}
\indexauthor{Toledano Rebolo, O.}


\ReceivedDate{2009 October 14} 
\AcceptedDate{2010 April 17} 
\SetYear{2010}
\SetVolume{46}


\abstract{We present kinematic data for 211 bright planetary nebulae in eleven Local Group galaxies: M31 (137 PNe), 
M32 (13), M33 (33), Fornax (1), Sagittarius (3), NGC 147 (2), NGC 185 (5), NGC 205 (9), NGC 6822 (5), Leo A (1), and 
Sextans A (1). The data were acquired at the Observatorio Astron\'omico Nacional in the Sierra de San Pedro M\'artir 
using the 2.1 m telescope and the Manchester Echelle Spectrometer in the light of [\ion{O}{3}]$\lambda$5007 at a 
resolution of 11~km~s$^{-1}$. A few objects were observed in H$\alpha$. The internal kinematics of bright planetary 
nebulae do not depend strongly upon the metallicity or age of their progenitor stellar populations, though small 
systematic differences exist. The nebular  kinematics and H$\beta$ luminosity require that the nebular shells be 
accelerated during the early evolution of their central stars.  Thus, kinematics provides an additional argument 
favoring similar stellar progenitors for bright planetary nebulae in all galaxies.}

\resumen{Presentamos datos cinem\'aticos para 211 nebulosas planetarias brillantes en once galaxias del Grupo Local: 
M31 (137 NPs), M32 (13), M33 (33), Fornax (1), Sagittarius (3), NGC 147 (2), NGC 185 (5), NGC 205 (9), NGC 6822 (6), 
Leo A (1), y Sextans A (1). Adquirimos los datos en el Observatorio Astron\'omico Nacional en la Sierra de San Pedro 
M\'artir con el telescopio de 2.1 m y el espectr\'ometro Manchester Echelle en la l\'inea de [\ion{O}{3}]$\lambda$5007 
con una resoluci\'on de 11~km~s$^{-1}$. Observamos algunos objetos en H$\alpha$. La cinem\'atica de nebulosas planetarias 
brillantes no depende fuertemente de la metalicidad o la edad de la poblaci\'on estelar proge\-nitora en sus galaxias 
hu\'espedes, aunque existen peque\~nas diferencias sistem\'aticas. La cinem\'atica y la luminosidad en H$\beta$ de las 
c\'ascaras nebulares requieren la acele\-raci\'on de las c\'ascaras durante la evoluci\'on temprana de las estrellas 
centrales.  As\'i, la cinem\'atica representa otro argumento a favor de estrellas progenitoras similares para las 
nebulosas planetarias brillantes en todas galaxias.}


\addkeyword{ISM: kinematics and dynamics}
\addkeyword{Local Group}
\addkeyword{planetary nebulae: general}
\addkeyword{stars: evolution}



\begin{document}

\maketitle

\section{Introduction}
\label{introduction}

Planetary nebulae are the immediate descendants of asymptotic giant branch (AGB) stars of low and intermediate masses 
($1~M_{\odot} < M < 8~M_{\odot}$). The mass lost on the AGB (or part of it) is seen as the ionized nebular shell in 
planetary nebulae. The composition of these nebular shells is extremely useful in studying the nucleosynthetic production 
of their precursor stars. The cycling of matter through these stars and its transformation is part of the chemical 
evolution of galaxies, since the progenitors of planetary nebulae are responsible for much of the helium, carbon, 
nitrogen, and some s-process elements in the universe.  

The luminosity function of bright extragalactic planetary nebulae (PNLF) has been used extensively as a distance indicator 
for about two decades (Jacoby 1989; Ciardullo et al. 1989b). While some progress has been made in understanding the nature 
of the progenitor stars of bright planetary nebulae \citep[e.g.,][]{richermccall2008}, the comments made by \citet{pottasch1990} 
are still largely valid: ``It may seem rather strange to determine the distance to the galactic centre by calibrating against 
the much more distant galaxy M31, but it is no stranger than the idea of using PN as standard candles in the first place, 
since individual distances to PN are so poorly known.''

Bright extragalactic planetary nebulae have two key advantages for evolutionary studies with respect to their Galactic 
counterparts. First, their distances are known, so their absolute luminosities are studied easily. Second, in galaxies 
more distant than the Magellanic Clouds, planetary nebulae are unresolved for ground-based observations, making it easy 
to study their integrated spectral properties, even at high spectral resolution. The drawback, of course, is the lack 
(usually) of spatial resolution available for Galactic planetary nebulae that is so useful in studying physical processes.  

Over the past decade, a substantial quantity of low resolution spectroscopy has been acquired (e.g. Jacoby \& Ciardullo 1999; 
Walsh et al. 1999; Roth et al. 2004; M\'endez et al. 2005; Pe\~na, Richer, \& Stasi\'nska 2007; Richer \& McCall 2008; 
Magrini \& Gon\c alves 2009). On the other hand, the only high resolution spectroscopy of extragalactic planetary nebulae 
suitable for studying their internal kinematics is that of \citet{zijlstraetal2006} and \citet{arnaboldietal2008}, apart from 
the pioneering efforts of \citet{dopitaetal1985, dopitaetal1988}. Here, we present our high resolution spectroscopic observations 
of 211 planetary nebulae in 11 Local Group galaxies. For the first time, these data allow redundant comparisons across different 
stellar populations. This study is part of a larger effort to understand the systematics of planetary nebula kinematics within 
our Milky Way and the Local Group. L\'opez et al. (2010, in preparation) present our results for Galactic planetary nebulae.  


%%%%% TABLA 1

\begin{table}[!t]
\vspace{0.1cm}
\centering
%\setlength{\tabnotewidth}{0.5\columnwidth}
\tablecols{2}
\caption{Observing Runs} 
\label{tab_obs_run}
\small
\begin{tabular}{ll}
\toprule
\multicolumn{1}{c}{Run} & \multicolumn{1}{c}{Dates} \\
\midrule
2001sep & 2001 Sep 21--26 \\
2002jul & 2002 Jul 23--24 \\
2002oct & 2002 Oct 31--2002 Nov 05 \\
2003oct & 2003 Oct 14--19 \\
2004jun & 2004 Jun 10--16 and 20--26 \\
2004nov & 2004 Nov 19--25 \\
2004dec & 2004 Dec 17--18 \\
2005jul & 2005 Jul 22--31 \\
2005sep & 2005 Sep 10--15 \\
2006sep & 2006 Sep 05--12 \\
2007feb & 2007 Feb 01--08 \\
2007aug & 2007 Aug 18--27 \\
\bottomrule
\end{tabular}
\vspace{0.2cm}
\end{table}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%


We present our observations and the data reduction in \S~\ref{observations}. We explain the analysis as well as its limitations 
in \S~\ref{analysis}. The results follow in \S~\ref{results}. We argue that the [\ion{O}{3}]$\lambda 5007$ line width is an 
adequate description of the kinematics of the majority of the ionized gas. We demonstrate that our radial velocities are 
accurate and in agreement with extant data. We find that the average line widths for bright planetary nebulae in all galaxies 
are similar, though there is a trend of decreasing line width with nuclear distance in the disc of M31. In \S~\ref{discussion}, 
we consider the implications of the foregoing, the most important being that the progenitor stars of bright planetary 
nebulae in all galaxies span a relatively small range in mass and that the central star plays an important role in accelerating 
the ionized shells of these objects. \S~\ref{conclusions} summarizes our conclusions.

Here, we focus on what we can learn of the evolution of bright extragalactic planetary nebulae and their progenitor stars from 
their [\ion{O}{3}]$\lambda 5007$ line widths. We make no attempt to investigate the kinematics of individual objects nor to 
interpret the line widths in terms of internal kinematics, as our spatially-integrated line profiles make this very difficult.  


%%%%%% TABLA 2

\setcounter{table}{1}
\begin{table*}[!t]
\vspace{0.1cm}
\centering
\setlength{\tabnotewidth}{0.9\textwidth}
\tablecols{7}
\setlength{\tabcolsep}{1.5\tabcolsep}
\caption{[\ion{O}{3}]$\lambda$5007 data for extragalactic planetary nebulae}
\label{tab_o3}
\footnotesize
\begin{tabular}{llccccl}
\toprule
\multicolumn{1}{c}{Galaxy} & \multicolumn{1}{c}{Object} & Flux\tabnotemark{a} & FWHM & $V_\mathrm{helio}$\tabnotemark{b} & $\Delta V_{0.5}$ & \multicolumn{1}{c}{Run} \\    
       &        & $(10^3\,\mathrm{ADU})$ & (\AA) & (km/s)                            & (km/s) &      \\
\midrule
Fornax      & PN1         & $40.5\pm 0.4$   & $ 0.353\pm 0.004 $   & $ ~~~51.2\pm 0.1$   & $ ~8.4\pm 0.1 $   & 2004nov \\
Leo A       & PN1         & $16.5\pm 0.4$   & $ 0.65\pm 0.02   $   & $ ~~~32.4\pm 0.4$   & $ 18.3\pm 0.5 $   & 2004jun, 2004nov \\
M31         & f08n04      & $~6.9\pm 0.2$   & $ 0.53\pm 0.02   $   & $ -381.7\pm 0.5 $   & $ 14.6\pm 0.6 $   & 2005sep \\
M31         & f08n05      & $10.2\pm 0.3$   & $ 0.79\pm 0.03   $   & $ -148.0\pm 0.7 $   & $ 22.7\pm 0.8 $   & 2004nov \\
M31         & f08n08      & $~7.0\pm 0.2$   & $ 0.67\pm 0.02   $   & $ -229.2\pm 0.5 $   & $ 18.9\pm 0.6 $   & 2005sep \\
M31         & f08n09      & $~8.1\pm 0.2$   & $ 0.424\pm 0.009 $   & $ ~-54.5\pm 0.2 $   & $ 10.9\pm 0.3 $   & 2004nov \\
M31         & f08n10      & $~7.8\pm 0.3$   & $ 0.85\pm 0.03   $   & $ ~-50.9\pm 0.8 $   & $ 24.6\pm 0.9 $   & 2005sep \\
M31         & f15n12002   & $~9.2\pm 0.2$   & $ 0.50\pm 0.01   $   & $ ~-90.8\pm 0.3 $   & $ 13.6\pm 0.3 $   & 2005sep \\
M31         & f29n2065    & $~4.2\pm 0.2$   & $ 0.76\pm 0.04   $   & $ -474~~\pm 1~~ $   & $ 22~~\pm 1~~ $   & 2007aug \\
M31         & f29n9178    & $~5.5\pm 0.1$   & $ 0.52\pm 0.02   $   & $ -524.1\pm 0.4 $   & $ 14.1\pm 0.5 $   & 2007aug \\
M31         & f32n1       & $~5.9\pm 0.2$   & $ 0.59\pm 0.03   $   & $ -371.8\pm 0.6 $   & $ 16.4\pm 0.7 $   & 2004nov \\
M31         & fjchp51     & $~3.7\pm 0.2$   & $ 0.54\pm 0.03   $   & $ -503.0\pm 0.8 $   & $ 15~~\pm 1~~ $   & 2007jan \\
M31         & fjchp57     & $~5.2\pm 0.2$   & $ 0.54\pm 0.03   $   & $ -141.9\pm 0.7 $   & $ 14.7\pm 0.8 $   & 2007aug \\
M31         & M0050       & $13.7\pm 0.2$   & $ 0.549\pm 0.008 $   & $ ~-35.7\pm 0.2 $   & $ 15.1\pm 0.2 $   & 2005sep \\
M31         & M0273       & $~8.9\pm 0.2$   & $ 0.84\pm 0.02   $   & $ -132.0\pm 0.5 $   & $ 24.2\pm 0.7 $   & 2005sep \\
M31         & M0319       & $14.5\pm 0.2$   & $ 0.546\pm 0.009 $   & $ -137.2\pm 0.2 $   & $ 15.0\pm 0.3 $   & 2005sep \\
M31         & M0442       & $12.8\pm 0.2$   & $ 0.597\pm 0.009 $   & $ ~-86.0\pm 0.2 $   & $ 16.7\pm 0.3 $   & 2005sep \\
M31         & M1232       & $~2.9\pm 0.2$   & $ 0.85\pm 0.06   $   & $ -174~~\pm 1~~ $   & $ 25~~\pm 2~~ $   & 2006sep \\
M31         & M1296       & $~1.6\pm 0.2$   & $ 0.68\pm 0.08   $   & $ ~-90~~\pm 2~~ $   & $ 19~~\pm 2~~ $   & 2001sep \\
M31         & M1558       & $12.2\pm 0.2$   & $ 0.59\pm 0.01   $   & $ -349.7\pm 0.3 $   & $ 16.5\pm 0.4 $   & 2005sep \\
M31         & M1596       & $~8.0\pm 0.2$   & $ 0.76\pm 0.02   $   & $ -374.5\pm 0.5 $   & $ 21.7\pm 0.7 $   & 2007aug \\
M31         & M1980       & $~7.5\pm 0.2$   & $ 0.67\pm 0.02   $   & $ -417.1\pm 0.4 $   & $ 18.9\pm 0.5 $   & 2005sep \\
M31         & M2357       & $~5.8\pm 0.2$   & $ 0.58\pm 0.02   $   & $ -561.7\pm 0.5 $   & $ 16.1\pm 0.7 $   & 2004nov \\
M31         & M2371       & $~8.6\pm 0.2$   & $ 0.67\pm 0.02   $   & $ -463.5\pm 0.4 $   & $ 19.0\pm 0.5 $   & 2004nov \\
M31         & M2401       & $~9.1\pm 0.2$   & $ 0.56\pm 0.01   $   & $ -437.0\pm 0.3 $   & $ 15.5\pm 0.3 $   & 2004nov \\
M31         & M2404       & $21.0\pm 0.3$   & $ 0.65\pm 0.01   $   & $ -379.6\pm 0.3 $   & $ 18.2\pm 0.4 $   & 2004nov \\
M31         & M2410       & $13.1\pm 0.5$   & $ 0.92\pm 0.04   $   & $ -436.2\pm 0.9 $   & $ 27~~\pm 1~~ $   & 2004nov \\
M31         & M2437       & $12.2\pm 0.3$   & $ 0.74\pm 0.02   $   & $ ~-73.8\pm 0.5 $   & $ 21.2\pm 0.6 $   & 2004nov \\
M31         & M2466       & $~4.8\pm 0.2$   & $ 0.46\pm 0.02   $   & $ -412.5\pm 0.5 $   & $ 12.2\pm 0.6 $   & 2005sep \\
M31         & M2496       & $11.7\pm 0.2$   & $ 0.534\pm 0.009 $   & $ -353.7\pm 0.2 $   & $ 14.6\pm 0.3 $   & 2004nov \\
M31         & M2501       & $~3.2\pm 0.2$   & $ 0.66\pm 0.06   $   & $ -386~~\pm 1~~ $   & $ 19~~\pm 1~~ $   & 2004nov \\
M31         & M2502       & $~3.6\pm 0.2$   & $ 0.65\pm 0.04   $   & $ -428.5\pm 0.9 $   & $ 19~~\pm 1~~ $   & 2004nov \\
M31         & M2507       & $~9.8\pm 0.3$   & $ 0.61\pm 0.02   $   & $ -184.7\pm 0.4 $   & $ 16.9\pm 0.5 $   & 2004nov \\
M31         & M2512       & $~6.6\pm 0.3$   & $ 0.61\pm 0.03   $   & $ -315.6\pm 0.8 $   & $ 17~~\pm 1~~ $   & 2004nov \\
M31         & M2514       & $~4.1\pm 0.3$   & $ 0.61\pm 0.04   $   & $ -453~~\pm 1~~ $   & $ 17~~\pm 1~~ $   & 2004nov \\
M31         & M2519       & $~6.0\pm 0.2$   & $ 0.55\pm 0.02   $   & $ -480.4\pm 0.4 $   & $ 15.2\pm 0.5 $   & 2004nov \\
M31         & M2538       & $11.5\pm 0.1$   & $ 0.434\pm 0.006 $   & $ -444.3\pm 0.1 $   & $ 11.3\pm 0.2 $   & 2007aug \\
M31         & M2694       & $10.2\pm 0.2$   & $ 0.53\pm 0.01   $   & $ -240.5\pm 0.3 $   & $ 14.6\pm 0.4 $   & 2005sep \\
M31         & M2860       & $~9.2\pm 0.2$   & $ 0.68\pm 0.02   $   & $ -413.4\pm 0.4 $   & $ 19.3\pm 0.5 $   & 2005sep \\
M31         & M2943       & $~8.9\pm 0.2$   & $ 0.53\pm 0.01   $   & $ -329.4\pm 0.3 $   & $ 14.6\pm 0.3 $   & 2007aug \\
M31         & M2985       & $~6.7\pm 0.2$   & $ 0.46\pm 0.01   $   & $ -431.9\pm 0.3 $   & $ 12.2\pm 0.4 $   & 2004nov \\
M31         & M2988       & $~5.0\pm 0.2$   & $ 0.49\pm 0.02   $   & $ -116.7\pm 0.6 $   & $ 13.0\pm 0.7 $   & 2004nov \\
M31         & M3246       & $~7.8\pm 0.2$   & $ 0.68\pm 0.02   $   & $ -542.9\pm 0.4 $   & $ 19.3\pm 0.5 $   & 2005sep \\
M31         & PN001       & $~7.0\pm 0.3$   & $ 0.66\pm 0.03   $   & $ -418.8\pm 0.8 $   & $ 19.0\pm 1~~ $   & 2001sep \\
M31         & PN003       & $~4.9\pm 0.3$   & $ 0.56\pm 0.04   $   & $ -273~~\pm 1~~ $   & $ 15~~\pm 1~~ $   & 2006sep \\
M31         & PN008       & $~5.7\pm 0.3$   & $ 0.65\pm 0.04   $   & $ -241~~\pm 1~~ $   & $ 18~~\pm 1~~ $   & 2006sep \\
M31         & PN010       & $~4.5\pm 0.3$   & $ 0.61\pm 0.05   $   & $ -157~~\pm 1~~ $   & $ 17~~\pm 2~~ $   & 2001sep \\
M31         & PN012       & $~4.7\pm 0.3$   & $ 0.79\pm 0.06   $   & $ -236~~\pm 2~~ $   & $ 23~~\pm 2~~ $   & 2007jan \\
M31         & PN015       & $10.5\pm 0.6$   & $ 0.99\pm 0.06   $   & $ -351~~\pm 2~~ $   & $ 29~~\pm 2~~ $   & 2001sep, 2005sep \\
M31         & PN017       & $~2.1\pm 0.2$   & $ 0.61\pm 0.05   $   & $ -495~~\pm 1~~ $   & $ 17~~\pm 1~~ $   & 2001sep \\
M31         & PN018       & $~3.9\pm 0.3$   & $ 0.62\pm 0.05   $   & $ -507~~\pm 1~~ $   & $ 17~~\pm 1~~ $   & 2001sep \\
M31         & PN023       & $~7.1\pm 0.3$   & $ 0.72\pm 0.03   $   & $ -231.2\pm 0.8 $   & $ 20~~\pm 1~~ $   & 2006sep \\
\bottomrule
\end{tabular}
\end{table*}


%%%%% CONTINUA TABLA 2

\setcounter{table}{1}
\begin{table*}[!t]
\vspace{0.1cm}
\centering
\centerline{TABLE~2 (CONTINUED)\smallskip}
\setlength{\tabnotewidth}{0.9\textwidth}
\tablecols{7}
\setlength{\tabcolsep}{1.5\tabcolsep}
\footnotesize
\begin{tabular}{llccccl}
\toprule
\multicolumn{1}{c}{Galaxy} & \multicolumn{1}{c}{Object} & Flux\tabnotemark{a} & FWHM & $V_\mathrm{helio}$\tabnotemark{b} & $\Delta V_{0.5}$ & \multicolumn{1}{c}{Run} \\    
       &        & $(10^3\,\mathrm{ADU})$ & (\AA) & (km/s)                            & (km/s) &      \\
\midrule
M31         & PN024       & $~4.9\pm 0.2$   & $ 0.69\pm 0.04   $   & $ -273.5\pm 0.9 $   & $ 20~~\pm 1~~ $   & 2001sep, 2005sep \\
M31         & PN026       & $~6.3\pm 0.3$   & $ 0.56\pm 0.03   $   & $ -400.2\pm 0.7 $   & $ 15.4\pm 0.9 $   & 2001sep \\
M31         & PN027       & $~6.4\pm 0.2$   & $ 0.89\pm 0.03   $   & $ -135.3\pm 0.8 $   & $ 26~~\pm 1~~ $   & 2006sep \\
M31         & PN028       & $~4.5\pm 0.3$   & $ 0.80\pm 0.07   $   & $ -256~~\pm 2~~ $   & $ 23~~\pm 2~~ $   & 2001sep \\
M31         & PN029       & $~5.8\pm 0.4$   & $ 0.97\pm 0.06   $   & $ -456~~\pm 2~~ $   & $ 28~~\pm 2~~ $   & 2001sep, 2005sep \\
M31         & PN030       & $11.4\pm 0.4$   & $ 1.03\pm 0.04   $   & $ -279~~\pm 1~~ $   & $ 30~~\pm 1~~ $   & 2001sep, 2007jan \\
M31         & PN031       & $~6.2\pm 0.2$   & $ 0.57\pm 0.02   $   & $ -226.5\pm 0.6 $   & $ 15.8\pm 0.7 $   & 2001sep \\
M31         & PN032       & $16.8\pm 0.6$   & $ 0.90\pm 0.03   $   & $ -119.5\pm 0.8 $   & $ 26~~\pm 1~~ $   & 2001sep, 2005sep \\
M31         & PN033       & $~4.8\pm 0.2$   & $ 0.63\pm 0.03   $   & $ ~131.7\pm 0.8 $   & $ 18~~\pm 1~~ $   & 2007jan \\
M31         & PN035       & $~4.4\pm 0.3$   & $ 0.71\pm 0.05   $   & $ -372~~\pm 1~~ $   & $ 20~~\pm 1~~ $   & 2001sep, 2005sep \\
M31         & PN036       & $~1.9\pm 0.2$   & $ 0.58\pm 0.07   $   & $ -183~~\pm 2~~ $   & $ 16~~\pm 2~~ $   & 2001sep \\
M31         & PN037       & $~1.9\pm 0.3$   & $ 0.8\pm 0.1     $   & $ -346~~\pm 3~~ $   & $ 23~~\pm 4~~ $   & 2001sep \\
M31         & PN038       & $~5.2\pm 0.2$   & $ 0.71\pm 0.03   $   & $ -319.1\pm 0.8 $   & $ 20~~\pm 1~~ $   & 2007jan \\
M31         & PN042       & $~8.7\pm 0.2$   & $ 0.55\pm 0.01   $   & $ -390.1\pm 0.3 $   & $ 15.2\pm 0.3 $   & 2005jul \\
M31         & PN043       & $~5.8\pm 0.2$   & $ 0.63\pm 0.02   $   & $ ~-93.3\pm 0.5 $   & $ 17.7\pm 0.7 $   & 2006sep \\
M31         & PN045       & $14.8\pm 0.3$   & $ 0.55\pm 0.01   $   & $ -255.0\pm 0.3 $   & $ 15.1\pm 0.4 $   & 2001sep \\
M31         & PN046       & $14.6\pm 0.4$   & $ 0.57\pm 0.02   $   & $ -457.2\pm 0.4 $   & $ 15.7\pm 0.5 $   & 2005jul \\
M31         & PN047       & $14.2\pm 0.4$   & $ 0.61\pm 0.02   $   & $ -316.7\pm 0.5 $   & $ 17.2\pm 0.6 $   & 2005jul \\
M31         & PN048       & $14.6\pm 0.2$   & $ 0.76\pm 0.01   $   & $ -237.5\pm 0.3 $   & $ 21.8\pm 0.3 $   & 2005sep \\
M31         & PN049       & $~3.2\pm 0.2$   & $ 0.59\pm 0.04   $   & $ -334~~\pm 1~~ $   & $ 17~~\pm 1~~ $   & 2005jul \\
M31         & PN052       & $~4.8\pm 0.2$   & $ 0.59\pm 0.03   $   & $ -153.4\pm 0.6 $   & $ 16.5\pm 0.8 $   & 2005sep \\
M31         & PN053       & $~7.1\pm 0.2$   & $ 0.45\pm 0.01   $   & $ -270.3\pm 0.4 $   & $ 11.8\pm 0.4 $   & 2001sep \\
M31         & PN054       & $~8.3\pm 0.2$   & $ 0.48\pm 0.01   $   & $ -499.7\pm 0.3 $   & $ 13.0\pm 0.4 $   & 2005sep \\
M31         & PN055       & $~4.1\pm 0.2$   & $ 0.75\pm 0.04   $   & $ -492.8\pm 0.9 $   & $ 22~~\pm 1~~ $   & 2005sep \\
M31         & PN056       & $~7.6\pm 0.2$   & $ 0.54\pm 0.01   $   & $ -252.1\pm 0.4 $   & $ 14.7\pm 0.4 $   & 2005sep \\
M31         & PN058       & $~5.5\pm 0.3$   & $ 0.74\pm 0.04   $   & $ -420~~\pm 1~~ $   & $ 21~~\pm 1~~ $   & 2006sep \\
M31         & PN061       & $~8.7\pm 0.3$   & $ 0.67\pm 0.02   $   & $ -183.4\pm 0.6 $   & $ 19.0\pm 0.7 $   & 2001sep, 2005sep \\
M31         & PN062       & $~8.3\pm 0.3$   & $ 0.69\pm 0.02   $   & $ -570.2\pm 0.6 $   & $ 19.6\pm 0.7 $   & 2006sep \\
M31         & PN064       & $~2.3\pm 0.2$   & $ 0.61\pm 0.07   $   & $ -609~~\pm 2~~ $   & $ 17~~\pm 2~~ $   & 2001sep \\
M31         & PN067       & $19.0\pm 0.3$   & $ 0.498\pm 0.008 $   & $ -410.6\pm 0.2 $   & $ 13.4\pm 0.2 $   & 2005sep \\
M31         & PN069       & $~3.8\pm 0.2$   & $ 0.76\pm 0.05   $   & $ -522~~\pm 1 ~~$   & $ 22~~\pm 2~~ $   & 2005sep \\
M31         & PN071       & $~2.5\pm 0.2$   & $ 0.71\pm 0.05   $   & $ -229~~\pm 1 ~~$   & $ 20~~\pm 2~~ $   & 2007jan \\
M31         & PN072       & $~5.4\pm 0.4$   & $ 0.54\pm 0.04   $   & $ -351~~\pm 1 ~~$   & $ 15~~\pm 1~~ $   & 2005sep \\
M31         & PN075       & $~5.6\pm 0.4$   & $ 0.81\pm 0.06   $   & $ -398~~\pm 1 ~~$   & $ 23~~\pm 2~~ $   & 2007jan \\
M31         & PN080       & $11.0\pm 0.3$   & $ 0.73\pm 0.02   $   & $ -299.7\pm 0.5 $   & $ 20.9\pm 0.6 $   & 2007jan \\
M31         & PN087       & $~3.4\pm 0.3$   & $ 0.70\pm 0.07   $   & $ -381~~\pm 2 ~~$   & $ 20~~\pm 2~~ $   & 2001sep, 2007jan \\
M31         & PN091       & $~6.5\pm 0.2$   & $ 0.80\pm 0.03   $   & $ -182.0\pm 0.7 $   & $ 23.0\pm 0.8 $   & 2007jan \\
M31         & PN092       & $~8.0\pm 0.2$   & $ 0.49\pm 0.01   $   & $ -275.0\pm 0.3 $   & $ 13.1\pm 0.3 $   & 2005sep \\
M31         & PN093       & $~4.5\pm 0.2$   & $ 0.85\pm 0.05   $   & $ -546~~\pm 1 ~~$   & $ 25~~\pm 1~~ $   & 2006sep \\
M31         & PN095       & $~4.4\pm 0.1$   & $ 0.42\pm 0.02   $   & $ -394.3\pm 0.4 $   & $ 10.8\pm 0.4 $   & 2006sep \\
M31         & PN097       & $~8.4\pm 0.2$   & $ 0.64\pm 0.01   $   & $ -480.0\pm 0.3 $   & $ 17.9\pm 0.4 $   & 2005sep \\
M31         & PN116       & $~8.9\pm 0.2$   & $ 0.66\pm 0.02   $   & $ -350.1\pm 0.4 $   & $ 18.8\pm 0.5 $   & 2005sep \\
M31         & PN125       & $~5.0\pm 0.2$   & $ 0.55\pm 0.03   $   & $ -227.6\pm 0.7 $   & $ 15.1\pm 0.8 $   & 2006sep \\
M31         & PN131       & $~5.0\pm 0.1$   & $ 0.53\pm 0.02   $   & $ -339.3\pm 0.4 $   & $ 14.4\pm 0.5 $   & 2005sep \\
M31         & pn136       & $~3.4\pm 0.3$   & $ 0.73\pm 0.06   $   & $ -329~~\pm 2 ~~$   & $ 21~~\pm 2~~ $   & 2007jan \\
M31         & PN142       & $~3.1\pm 0.2$   & $ 0.62\pm 0.04   $   & $ -259~~\pm 1 ~~$   & $ 17~~\pm 1~~ $   & 2005jul \\
M31         & PN143       & $~1.6\pm 0.2$   & $ 1.0\pm 0.1     $   & $ -267~~\pm 3 ~~$   & $ 28~~\pm 4~~ $   & 2005sep \\
M31         & PN150       & $~5.4\pm 0.2$   & $ 0.64\pm 0.02   $   & $ -136.2\pm 0.6 $   & $ 18.2\pm 0.7 $   & 2005sep \\
M31         & PN151       & $~6.8\pm 0.2$   & $ 0.76\pm 0.02   $   & $ -562.1\pm 0.6 $   & $ 22.0\pm 0.7 $   & 2005sep \\
M31         & PN154       & $~7.3\pm 0.2$   & $ 0.55\pm 0.01   $   & $ -349.3\pm 0.3 $   & $ 15.2\pm 0.4 $   & 2005sep \\
M31         & PN155       & $~9.8\pm 0.2$   & $ 0.69\pm 0.01   $   & $ -241.6\pm 0.3 $   & $ 19.5\pm 0.4 $   & 2005sep \\
M31         & PN172       & $~8.9\pm 0.2$   & $ 0.82\pm 0.02   $   & $ -247.2\pm 0.5 $   & $ 23.6\pm 0.6 $   & 2005sep \\
M31         & PN177       & $~4.1\pm 0.2$   & $ 0.58\pm 0.04   $   & $ -300.3\pm 0.9 $   & $ 16~~\pm 1~~ $   & 2007jan \\
M31         & PN178       & $11.8\pm 0.2$   & $ 0.58\pm 0.01   $   & $ -213.8\pm 0.3 $   & $ 16.1\pm 0.3 $   & 2005sep \\
\bottomrule
\end{tabular}
\end{table*}


%%%%%%%% CONTINUA TABLA 2

\setcounter{table}{1}
\begin{table*}[!t]
\vspace{0.1cm}
\centering
\centerline{TABLE~2 (CONTINUED)\smallskip}
\setlength{\tabnotewidth}{0.9\textwidth}
\tablecols{7}
\setlength{\tabcolsep}{1.5\tabcolsep}
\footnotesize
\begin{tabular}{llccccl}
\toprule
\multicolumn{1}{c}{Galaxy} & \multicolumn{1}{c}{Object} & Flux\tabnotemark{a} & FWHM & $V_\mathrm{helio}$\tabnotemark{b} & $\Delta V_{0.5}$ & \multicolumn{1}{c}{Run} \\    
       &        & $(10^3\,\mathrm{ADU})$ & (\AA) & (km/s)                            & (km/s) &      \\
\midrule
M31         & pn179       & $~4.0\pm 0.2$   & $ 0.62\pm 0.04   $   & $ -124.6\pm 0.9 $   & $ 17~~\pm 1~~ $   & 2007jan \\
M31         & PN190       & $~4.8\pm 0.2$   & $ 0.48\pm 0.02   $   & $ -113.2\pm 0.5 $   & $ 12.9\pm 0.7 $   & 2007jan \\
M31         & PN209       & $~6.1\pm 0.2$   & $ 0.47\pm 0.01   $   & $ -320.9\pm 0.3 $   & $ 12.6\pm 0.4 $   & 2005sep \\
M31         & PN216       & $~7.2\pm 0.2$   & $ 0.43\pm 0.01   $   & $ -229.1\pm 0.3 $   & $ 11.2\pm 0.3 $   & 2005sep \\
M31         & PN219       & $~5.1\pm 0.2$   & $ 0.71\pm 0.03   $   & $ -140.9\pm 0.7 $   & $ 20.2\pm 0.8 $   & 2005sep \\
M31         & PN237       & $~5.3\pm 0.2$   & $ 0.87\pm 0.04   $   & $ ~-64.7\pm 0.9 $   & $ 25~~\pm 1~~ $   & 2005sep \\
M31         & PN240       & $11.0\pm 0.2$   & $ 0.61\pm 0.01   $   & $ ~-95.1\pm 0.3 $   & $ 17.2\pm 0.4 $   & 2005sep \\
M31         & PN278       & $~4.2\pm 0.3$   & $ 0.75\pm 0.05   $   & $ -135~~\pm 1~~ $   & $ 21~~\pm 2~~ $   & 2005sep \\
M31         & PN290       & $~3.4\pm 0.2$   & $ 0.57\pm 0.03   $   & $ -658.6\pm 0.7 $   & $ 15.7\pm 0.9 $   & 2007jan \\
M31         & PN335       & $~3.5\pm 0.2$   & $ 0.74\pm 0.04   $   & $ -446.1\pm 0.9 $   & $ 21~~\pm 1~~ $   & 2004nov \\
M31         & PN344       & $~8.5\pm 0.2$   & $ 0.60\pm 0.01   $   & $ -505.2\pm 0.3 $   & $ 16.7\pm 0.4 $   & 2004nov \\
M31         & PN345       & $~9.8\pm 0.2$   & $ 0.60\pm 0.02   $   & $ -490.4\pm 0.4 $   & $ 16.8\pm 0.5 $   & 2004nov \\
M31         & PN349       & $~6.4\pm 0.2$   & $ 0.47\pm 0.01   $   & $ -494.5\pm 0.3 $   & $ 12.6\pm 0.4 $   & 2004nov \\
M31         & PN353       & $~6.9\pm 0.2$   & $ 0.74\pm 0.02   $   & $ -257.3\pm 0.5 $   & $ 21.1\pm 0.6 $   & 2004nov \\
M31         & PN363       & $~7.2\pm 0.2$   & $ 0.75\pm 0.02   $   & $ ~-95.6\pm 0.5 $   & $ 21.6\pm 0.6 $   & 2007aug \\
M31         & PN364       & $~6.8\pm 0.1$   & $ 0.309\pm 0.006 $   & $ -102.5\pm 0.1 $   & $ ~6.6\pm 0.2 $   & 2005sep \\
M31         & PN370       & $~5.7\pm 0.2$   & $ 0.41\pm 0.01   $   & $ ~-91.0\pm 0.3 $   & $ 10.4\pm 0.4 $   & 2004nov \\
M31         & PN375       & $11.5\pm 0.2$   & $ 0.71\pm 0.02   $   & $ -410.6\pm 0.4 $   & $ 20.1\pm 0.4 $   & 2005sep \\
M31         & PN380       & $13.3\pm 0.2$   & $ 0.66\pm 0.01   $   & $ -297.1\pm 0.3 $   & $ 18.7\pm 0.3 $   & 2005sep \\
M31         & PN387       & $~7.5\pm 0.2$   & $ 0.66\pm 0.02   $   & $ -254.6\pm 0.4 $   & $ 18.6\pm 0.5 $   & 2005sep \\
M31         & PN390       & $~9.8\pm 0.2$   & $ 0.83\pm 0.02   $   & $ -578.7\pm 0.5 $   & $ 23.9\pm 0.6 $   & 2005sep \\
M31         & PN410       & $~6.1\pm 0.2$   & $ 0.82\pm 0.03   $   & $ -530.3\pm 0.7 $   & $ 23.7\pm 0.8 $   & 2005sep \\
M31         & PN413       & $10.5\pm 0.3$   & $ 0.52\pm 0.01   $   & $ -317.6\pm 0.4 $   & $ 14.2\pm 0.4 $   & 2005sep \\
M31         & PN414       & $~5.1\pm 0.2$   & $ 0.73\pm 0.03   $   & $ ~~~37.6\pm 0.8$   & $ 20.7\pm 0.9 $   & 2005sep \\
M31         & PN450       & $~2.3\pm 0.2$   & $ 0.86\pm 0.06   $   & $ -361~~\pm 1~~ $   & $ 25~~\pm 2~~ $   & 2005sep \\
M31         & PN478       & $~5.6\pm 0.2$   & $ 0.47\pm 0.02   $   & $ -115.9\pm 0.5 $   & $ 12.6\pm 0.6 $   & 2007jan \\
M31         & PN537       & $~7.8\pm 0.1$   & $ 0.425\pm 0.009 $   & $ -154.8\pm 0.2 $   & $ 11.0\pm 0.3 $   & 2005sep \\
M31         & PN555       & $11.2\pm 0.2$   & $ 0.80\pm 0.02   $   & $ ~-98.5\pm 0.4 $   & $ 23.1\pm 0.6 $   & 2005sep \\
M31         & PN557       & $~7.1\pm 0.2$   & $ 0.66\pm 0.02   $   & $ ~-70.2\pm 0.5 $   & $ 18.8\pm 0.6 $   & 2005sep \\
M31         & PN559       & $11.9\pm 0.1$   & $ 0.520\pm 0.007 $   & $ -113.0\pm 0.2 $   & $ 14.2\pm 0.2 $   & 2005sep \\
M31         & PN563       & $~8.8\pm 0.3$   & $ 0.87\pm 0.03   $   & $ -157.5\pm 0.7 $   & $ 25.1\pm 0.9 $   & 2005sep \\
M31         & PN568       & $~7.9\pm 0.2$   & $ 0.69\pm 0.02   $   & $ -118.7\pm 0.5 $   & $ 19.8\pm 0.7 $   & 2005sep \\
M31         & PN569       & $~2.7\pm 0.2$   & $ 0.87\pm 0.06   $   & $ -148~~\pm 2~~ $   & $ 25~~\pm 2~~ $   & 2005sep \\
M32         & PN1         & $10.6\pm 0.3$   & $ 0.56\pm 0.02   $   & $ -206.7\pm 0.4 $   & $ 15.3\pm 0.5 $   & 2001sep, 2006sep \\
M32         & PN2         & $~6.6\pm 0.2$   & $ 0.66\pm 0.02   $   & $ -218.0\pm 0.6 $   & $ 18.8\pm 0.7 $   & 2006sep \\
M32         & PN3         & $~5.6\pm 0.2$   & $ 0.46\pm 0.02   $   & $ -169.3\pm 0.5 $   & $ 12.3\pm 0.6 $   & 2001sep \\
M32         & PN5         & $~5.5\pm 0.4$   & $ 0.80\pm 0.06   $   & $ -245~~\pm 1~~ $   & $ 23~~\pm 2~~ $   & 2001sep, 2006sep \\
M32         & PN6         & $~4.8\pm 0.3$   & $ 0.84\pm 0.06   $   & $ -206~~\pm 1~~ $   & $ 24~~\pm 2~~ $   & 2001sep, 2006sep \\
M32         & PN7         & $~5.6\pm 0.2$   & $ 0.42\pm 0.02   $   & $ -194.4\pm 0.5 $   & $ 10.8\pm 0.6 $   & 2001sep, 2006sep \\
M32         & PN8         & $~4.0\pm 0.3$   & $ 0.83\pm 0.06   $   & $ -168~~\pm 2~~ $   & $ 24~~\pm 2~~ $   & 2001sep \\
M32         & PN21        & $10.1\pm 0.5$   & $ 0.90\pm 0.05   $   & $ -192~~\pm 1~~ $   & $ 26~~\pm 1~~ $   & 2001sep, 2006sep \\
M32         & PN23        & $~3.5\pm 0.2$   & $ 0.87\pm 0.05   $   & $ -231~~\pm 1~~ $   & $ 25~~\pm 2~~ $   & 2006sep \\
M32         & PN24+PN25   & $~7.8\pm 0.2$   & $ 0.77\pm 0.03   $   & $ -171.1\pm 0.6 $   & $ 22.2\pm 0.7 $   & 2006sep \\
M32         & PN24        & $~3.8\pm 0.2$   & $ 0.82\pm 0.04   $   & $ -166.8\pm 0.9 $   & $ 24~~\pm 1~~ $   & 2006sep \\
M32         & PN25        & $~4.1\pm 0.2$   & $ 0.72\pm 0.03   $   & $ -174.8\pm 0.7 $   & $ 20.5\pm 0.9 $   & 2006sep \\
M32         & PN26        & $~3.5\pm 0.2$   & $ 0.91\pm 0.06   $   & $ -229~~\pm 2~~ $   & $ 26~~\pm 2~~ $   & 2006sep \\
M32         & PN29        & $~2.4\pm 0.2$   & $ 0.63\pm 0.06   $   & $ -646~~\pm 2~~ $   & $ 18~~\pm 2~~ $   & 2006sep \\
M33         & M002        & $~5.0\pm 0.3$   & $ 0.56\pm 0.03   $   & $ -126.9\pm 0.8 $   & $ 16~~\pm 1~~ $   & 2003oct \\
M33         & M005        & $~4.0\pm 0.2$   & $ 0.38\pm 0.02   $   & $ -125.5\pm 0.6 $   & $ ~9.5\pm 0.7 $   & 2003oct \\
M33         & M008        & $~4.4\pm 0.2$   & $ 0.45\pm 0.02   $   & $ -115.7\pm 0.5 $   & $ 11.9\pm 0.6 $   & 2003oct \\
M33         & M013        & $~3.2\pm 0.1$   & $ 0.44\pm 0.02   $   & $ -106.9\pm 0.6 $   & $ 11.5\pm 0.7 $   & 2002nov \\
M33         & M017        & $~7.0\pm 0.3$   & $ 0.57\pm 0.03   $   & $ -195.9\pm 0.7 $   & $ 15.8\pm 0.8 $   & 2002nov \\
M33         & M018        & $13.4\pm 0.3$   & $ 0.55\pm 0.01   $   & $ -155.2\pm 0.3 $   & $ 15.3\pm 0.4 $   & 2002nov \\
M33         & M028        & $~5.0\pm 0.2$   & $ 0.54\pm 0.03   $   & $ -161.4\pm 0.7 $   & $ 15.0\pm 0.9 $   & 2002nov \\
\bottomrule
\end{tabular}
\end{table*}


%%%%%%%%% CONTINUA TABLA 2

\setcounter{table}{1}
\begin{table*}[!t]
\vspace{0.1cm}
\centering
\centerline{TABLE~2 (CONTINUED)\smallskip}
\setlength{\tabnotewidth}{0.92\textwidth}
\tablecols{7}
\setlength{\tabcolsep}{1.5\tabcolsep}
\footnotesize
\begin{tabular}{llccccl}
\toprule
\multicolumn{1}{c}{Galaxy} & \multicolumn{1}{c}{Object} & Flux\tabnotemark{a} & FWHM & $V_\mathrm{helio}$\tabnotemark{b} & $\Delta V_{0.5}$ & \multicolumn{1}{c}{Run} \\    
       &        & $(10^3\,\mathrm{ADU})$ & (\AA) & (km/s)                            & (km/s) &      \\
\midrule
M33         & M042        & $14.4\pm 0.5$   & $ 0.79\pm 0.03   $   & $ -136.1\pm 0.7 $   & $ 22.7\pm 0.8 $   & 2002nov \\
M33         & M046        & $~5.0\pm 0.2$   & $ 0.37\pm 0.02   $   & $ -127.7\pm 0.4 $   & $ ~8.9\pm 0.5 $   & 2002nov \\
M33         & M059        & $~5.1\pm 0.2$   & $ 0.40\pm 0.02   $   & $ -113.3\pm 0.4 $   & $ 10.0\pm 0.5 $   & 2003oct \\
M33         & M061        & $~6.8\pm 0.3$   & $ 0.66\pm 0.03   $   & $ -115.3\pm 0.8 $   & $ 18.7\pm 0.9 $   & 2002nov \\
M33         & M062        & $~4.4\pm 0.2$   & $ 0.53\pm 0.03   $   & $ ~-98.3\pm 0.8 $   & $ 15~~\pm 1~~ $   & 2002nov \\
M33         & M063        & $~8.2\pm 0.3$   & $ 0.68\pm 0.03   $   & $ -111.5\pm 0.7 $   & $ 19.2\pm 0.8 $   & 2002nov \\
M33         & M065        & $~4.9\pm 0.2$   & $ 0.54\pm 0.03   $   & $ -170.7\pm 0.7 $   & $ 14.7\pm 0.9 $   & 2002nov \\
M33         & M067        & $11.0\pm 0.3$   & $ 0.64\pm 0.02   $   & $ -128.0\pm 0.5 $   & $ 18.1\pm 0.6 $   & 2002nov \\
M33         & M068        & $~7.1\pm 0.3$   & $ 0.50\pm 0.03   $   & $ -170.7\pm 0.6 $   & $ 13.4\pm 0.8 $   & 2002nov \\
M33         & M069        & $10.5\pm 0.5$   & $ 0.84\pm 0.05   $   & $ -168~~\pm 1~~ $   & $ 24~~\pm 1~~ $   & 2002nov \\
M33         & M072        & $~3.8\pm 0.2$   & $ 0.53\pm 0.03   $   & $ -267.5\pm 0.8 $   & $ 14.5\pm 0.9 $   & 2002nov \\
M33         & M074        & $~4.0\pm 0.3$   & $ 0.72\pm 0.06   $   & $ -168~~\pm 2~~ $   & $ 21~~\pm 2~~ $   & 2003oct \\
M33         & M075        & $~5.8\pm 0.2$   & $ 0.46\pm 0.02   $   & $ -259.8\pm 0.4 $   & $ 12.3\pm 0.5 $   & 2002nov \\
M33         & M079        & $~6.1\pm 0.3$   & $ 0.75\pm 0.04   $   & $ -165~~\pm 1~~ $   & $ 21~~\pm 1~~ $   & 2003oct \\
M33         & M089        & $~4.1\pm 0.3$   & $ 0.69\pm 0.05   $   & $ -272~~\pm 1~~ $   & $ 20~~\pm 2~~ $   & 2003oct \\
M33         & M091        & $24.0\pm 0.5$   & $ 0.70\pm 0.01   $   & $ -137.6\pm 0.4 $   & $ 19.8\pm 0.4 $   & 2002nov, 2003oct \\
M33         & M093        & $14.2\pm 0.4$   & $ 0.66\pm 0.02   $   & $ -171.6\pm 0.6 $   & $ 18.8\pm 0.7 $   & 2002nov, 2003oct \\
M33         & M094        & $13.4\pm 0.4$   & $ 0.57\pm 0.02   $   & $ -168.3\pm 0.5 $   & $ 15.8\pm 0.5 $   & 2002nov, 2003oct \\
M33         & M095        & $~4.1\pm 0.2$   & $ 0.46\pm 0.03   $   & $ -262.5\pm 0.7 $   & $ 12.1\pm 0.8 $   & 2002nov \\
M33         & M096        & $~8.6\pm 0.2$   & $ 0.44\pm 0.01   $   & $ -151.7\pm 0.3 $   & $ 11.5\pm 0.4 $   & 2003oct \\
M33         & M101        & $~7.1\pm 0.2$   & $ 0.51\pm 0.02   $   & $ -132.7\pm 0.4 $   & $ 13.9\pm 0.5 $   & 2003oct \\
M33         & M111        & $~8.9\pm 0.3$   & $ 0.70\pm 0.03   $   & $ -241.3\pm 0.7 $   & $ 20.0\pm 0.8 $   & 2003oct \\
M33         & M119        & $~8.1\pm 0.3$   & $ 0.81\pm 0.04   $   & $ -231.4\pm 0.9 $   & $ 23~~\pm 1~~ $   & 2003oct \\
M33         & M125        & $~3.3\pm 0.2$   & $ 0.64\pm 0.04   $   & $ -182~~\pm 1~~ $   & $ 18~~\pm 1~~ $   & 2003oct \\
M33         & M128        & $~4.8\pm 0.2$   & $ 0.34\pm 0.01   $   & $ -260.1\pm 0.3 $   & $ ~8.0\pm 0.4 $   & 2002nov \\
M33         & newPN       & $~6.2\pm 0.2$   & $ 0.35\pm 0.01   $   & $ -112.5\pm 0.2 $   & $ ~8.1\pm 0.3 $   & 2003oct \\
NGC147      & PN04        & $~2.8\pm 0.1$   & $ 0.34\pm 0.02   $   & $ -192.2\pm 0.5 $   & $ ~7.7\pm 0.6 $   & 2007jan \\
NGC147      & PN07        & $~3.8\pm 0.2$   & $ 0.53\pm 0.03   $   & $ -182.5\pm 0.9 $   & $ 15~~\pm 1~~ $   & 2007jan \\
NGC185      & PN01        & $10.5\pm 0.3$   & $ 0.73\pm 0.02   $   & $ -232.7\pm 0.6 $   & $ 20.9\pm 0.7 $   & 2001sep \\
NGC185      & PN02        & $~4.3\pm 0.1$   & $ 0.37\pm 0.01   $   & $ -206.0\pm 0.4 $   & $ ~8.8\pm 0.4 $   & 2001sep \\
NGC185      & PN03        & $~6.2\pm 0.3$   & $ 0.60\pm 0.03   $   & $ -213.1\pm 0.7 $   & $ 16.8\pm 0.8 $   & 2001sep, 2006sep \\
NGC185      & PN04        & $~3.5\pm 0.3$   & $ 0.71\pm 0.07   $   & $ -215~~\pm 2~~ $   & $ 20~~\pm 2~~ $   & 2006sep \\
NGC185      & PN05        & $~7.1\pm 0.4$   & $ 0.88\pm 0.05   $   & $ -245~~\pm 1~~ $   & $ 26~~\pm 1~~ $   & 2001sep, 2006sep \\
NGC205      & PN1         & $~4.5\pm 0.2$   & $ 0.31\pm 0.02   $   & $ -291.2\pm 0.4 $   & $ ~6.7\pm 0.4 $   & 2001sep \\
NGC205      & PN2         & $~5.2\pm 0.3$   & $ 0.74\pm 0.04   $   & $ -230~~\pm 1~~ $   & $ 21~~\pm 1~~ $   & 2007aug \\
NGC205      & PN4         & $~4.7\pm 0.2$   & $ 0.47\pm 0.03   $   & $ -251.1\pm 0.6 $   & $ 12.6\pm 0.7 $   & 2001sep \\
NGC205      & PN5         & $~6.7\pm 0.3$   & $ 0.58\pm 0.03   $   & $ -240.6\pm 0.6 $   & $ 16.0\pm 0.8 $   & 2001sep \\
NGC205      & PN6         & $~4.8\pm 0.3$   & $ 0.57\pm 0.04   $   & $ -210.1\pm 0.9 $   & $ 16~~\pm 1~~ $   & 2001sep \\
NGC205      & PN7         & $~5.2\pm 0.2$   & $ 0.33\pm 0.01   $   & $ -243.7\pm 0.3 $   & $ ~7.6\pm 0.3 $   & 2001sep \\
NGC205      & PN8         & $~3.7\pm 0.2$   & $ 0.58\pm 0.04   $   & $ -259.2\pm 0.9 $   & $ 16~~\pm 1~~ $   & 2001sep \\
NGC205      & PN9         & $~3.6\pm 0.2$   & $ 0.36\pm 0.02   $   & $ -241.4\pm 0.4 $   & $ ~8.5\pm 0.5 $   & 2001sep \\
NGC205      & PN10        & $~5.4\pm 0.3$   & $ 0.79\pm 0.04   $   & $ -220~~\pm 1~~ $   & $ 23~~\pm 1~~ $   & 2007aug \\
NGC6822     & PN1         & $~4.5\pm 0.2$   & $ 0.48\pm 0.02   $   & $ ~-73.0\pm 0.4 $   & $ 12.9\pm 0.5 $   & 2005jul \\
NGC6822     & PN19        & $~4.4\pm 0.2$   & $ 0.48\pm 0.03   $   & $ ~-69.0\pm 0.7 $   & $ 12.8\pm 0.8 $   & 2005jul \\
NGC6822     & S14         & $~5.0\pm 0.3$   & $ 0.62\pm 0.04   $   & $ -100.7\pm 0.9 $   & $ 17~~\pm 1~~ $   & 2002jul \\
NGC6822     & S16         & $11.3\pm 0.5$   & $ 0.60\pm 0.03   $   & $ ~-78.7\pm 0.7 $   & $ 16.7\pm 0.8 $   & 2002jul \\
NGC6822     & S30         & $~4.2\pm 0.2$   & $ 0.97\pm 0.06   $   & $ ~-60~~\pm 1~~ $   & $ 28~~\pm 2~~ $   & 2005jul \\
NGC6822     & S33         & $~7.5\pm 0.4$   & $ 0.85\pm 0.05   $   & $ ~-43~~\pm 1~~ $   & $ 25~~\pm 2~~ $   & 2002jul \\
Sagittarius & He 2-436    & $1480\pm 20$    & $ 0.474\pm 0.006 $   & $ ~131.6\pm 0.1 $   & $ 12.6\pm 0.2 $   & 2004juna \\
Sagittarius & StWr 2-21   & $218\pm 3$      & $ 0.94\pm 0.01   $   & $ ~116.7\pm 0.3 $   & $ 27.2\pm 0.4 $   & 2004junc \\
Sagittarius & Wray 16-423 & $3200\pm 30$    & $ 0.727\pm 0.007 $   & $ ~131.6\pm 0.2 $   & $ 20.8\pm 0.2 $   & 2004juna \\
Sextans A   & PN1         & $~5.0\pm 0.3$   & $ 0.88\pm 0.06   $   & $ ~~31~~\pm 1~~ $   & $ 26~~\pm 2~~ $   & 2004nov \\
\bottomrule
\noalign{\vspace{0.02cm}}
\tabnotetext{a}{The fluxes are not calibrated. See \S~\ref{observations} and \S~\ref{analysis}.} %\textsuperscript{
\tabnotetext{b}{The uncertainties listed are formal uncertainties. See \S~\ref{radial_velocities}.}
\end{tabular}
%\vspace{0.2cm}
\end{table*}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%


%%%%%% TABLA 3

\setcounter{table}{2}
\begin{table*}[!t]
\vspace{0.1cm}
\centering
\setlength{\tabnotewidth}{0.85\textwidth}
\tablecols{7}
\setlength{\tabcolsep}{1.5\tabcolsep}
\caption{H$\alpha$ data for extragalactic planetary nebulae} 
\label{tab_Ha}
\small
\begin{tabular}{llccccl}
\toprule
\multicolumn{1}{c}{Galaxy} & \multicolumn{1}{c}{Object} & Flux\tabnotemark{a}   & FWHM  & $V_\mathrm{helio}$\tabnotemark{b} & $\Delta V_{0.5}$ & \multicolumn{1}{c}{Run} \\
                           &                            & $(10^3~\mathrm{ADU})$ & (\AA) & (km~s$^{-1}$)                     & (km~s$^{-1}$)    & \\
\midrule
Fornax      & PN1        & $ ~35.4\pm 0.2 $ & $ 0.723\pm 0.005 $ & $ ~~~47.95\pm 0.09$ & $ 11.4~\pm 0.1~ $ & 2004nov  \\
M32         & PN3        & $ ~~4.0\pm 0.4 $ & $ 0.9~~\pm 0.1~~ $ & $ -157~~\pm 2~~   $ & $ 17~~\pm 2~~   $ & 2001sep  \\
M32         & PN6        & $ ~~4.3\pm 0.5 $ & $ 1.5~~\pm 0.2~~ $ & $ -185~~\pm 3~~   $ & $ 33~~\pm 4~~   $ & 2001sep  \\
M33         & M059       & $ ~~2.2\pm 0.3 $ & $ 0.8~~\pm 0.1~~ $ & $ -119~~\pm 2~~   $ & $ 13~~\pm 2~~   $ & 2003oct  \\
NGC6822     & PN19       & $ ~~4.8\pm 0.2 $ & $ 0.82~\pm 0.03~ $ & $ ~-70.5~\pm 0.5~ $ & $ 14.3~\pm 0.7~ $ & 2005jul  \\
NGC6822     & S14        & $ ~~3.1\pm 0.3 $ & $ 0.97~\pm 0.09~ $ & $ -104~~\pm 2~~   $ & $ 19~~\pm 2~~   $ & 2002jul  \\
NGC6822     & S16        & $ ~~3.7\pm 0.3 $ & $ 0.93~\pm 0.09~ $ & $ ~-76~~\pm 2~~   $ & $ 18~~\pm 2~~   $ & 2002jul  \\
NGC6822     & S30        & $ ~~6.7\pm 0.2 $ & $ 1.32~\pm 0.04~ $ & $ ~-64.1~\pm 0.7~ $ & $ 27.7~\pm 0.9~ $ & 2005jul  \\
NGC6822     & S33        & $ ~~7.0\pm 0.4 $ & $ 1.17~\pm 0.08~ $ & $ ~-44~~\pm 1~~   $ & $ 24~~\pm 2~~   $ & 2002jul  \\
Sagittarius & He 2-436   & $ 364~\pm  1~  $ & $ 0.820\pm 0.003 $ & $ ~129.16\pm 0.05 $ & $ 14.43\pm 0.06 $ & 2004juna \\
Sagittarius & StWr 2-21  & $ 171.4\pm 0.7 $ & $ 1.248\pm 0.005 $ & $ ~131.1~\pm 0.1~ $ & $ 25.9~\pm 0.1~ $ & 2004junc \\
Sagittarius & Wray 16-42 & $ 804~\pm  4~  $ & $ 1.057\pm 0.005 $ & $ ~128.8~\pm 0.1~ $ & $ 21.0~\pm 0.1~ $ & 2004juna \\
\bottomrule
\tabnotetext{a}{The fluxes are not calibrated. See \S~\ref{observations} and \S~\ref{analysis}.}
\tabnotetext{b}{The uncertainties listed are formal uncertainties. See \S~\ref{radial_velocities}.}
\end{tabular}
\vspace{0.2cm}
\end{table*}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%


%%%%% TABLA 4

\setcounter{table}{3}
\begin{table*}[!t]
\vspace{0.1cm}
\centering
\setlength{\tabnotewidth}{0.7\textwidth}
\tablecols{7}
\setlength{\tabcolsep}{1.5\tabcolsep}
\caption{[\ion{O}{3}]$\lambda$5007 Data for compact \ion{H}{2} regions} 
\label{tab_cHII}
\small
\begin{tabular}{llccccl}
\toprule
\multicolumn{1}{c}{Galaxy} & \multicolumn{1}{c}{Object} & Flux\tabnotemark{a}   & FWHM  & $V_\mathrm{helio}$\tabnotemark{b} 
& $\Delta V_{0.5}$ & \multicolumn{1}{c}{Run} \\
                           &                            & $(10^3~\mathrm{ADU})$ & (\AA) & (km~s$^{-1}$)      
& (km~s$^{-1}$)    &      \\
\midrule
NGC6822 & S10    & $8.4\pm 0.4$ & $0.59\pm 0.03$ & $-88.1\pm 0.8$ & $16\pm 1    $ & 2002jul \\
NGC3109 & PN07   & $6.9\pm 0.2$ & $0.47\pm 0.02$ & $385.7\pm 0.4$ & $12.6\pm 0.5$ & 2004nov \\
NGC3109 & PN10   & $2.7\pm 0.2$ & $0.60\pm 0.06$ & $409\pm 2    $ & $17\pm 2    $ & 2004dec \\
\bottomrule
\tabnotetext{a}{The fluxes are not calibrated. See \S~\ref{observations} and \S~\ref{analysis}.}
\tabnotetext{b}{The uncertainties listed are formal uncertainties. See \S~\ref{radial_velocities}.}
\end{tabular}
\vspace{0.3cm}
\end{table*}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%5555%%%%%%%%%%%%%%%%%%%%


\section{Observations and Data Reduction}
\label{observations}

The observations were obtained during twelve observing runs between 2001 September and 2007 August (see Table~\ref{tab_obs_run}). 
All of the data were acquired with the 2.1 m telescope  at the Observatorio Astron\'omico Nacional in the Sierra de San Pedro 
M\'atir (OAN-SPM) and the Manchester Echelle Spectrometer \citep[MES-SPM; ][]{meaburnetal1984, meaburnetal2003}. The MES-SPM is 
a long slit echelle spectrometer, but uses narrow-band filters, instead of a cross-disperser, to isolate the orders containing 
the emission lines of interest. In our case, filters isolated orders 87 and 114 containing the H$\alpha$ and [\ion{O}{3}]$\lambda 5007$ 
emission lines, respectively. All observations used a 150~$\mu$m wide slit, equivalent to $1\farcs9$ on the sky. When coupled with 
a SITe $1024 \times 1024$ CCD with 24~$\mu$m pixels binned $2 \times 2$, the resulting spectral resolutions were approximately 
0.077~\AA/pix and 0.100~\AA/pix at [\ion{O}{3}]$\lambda 5007$ and H$\alpha$, respectively (equivalent to 11~km~s$^{-1}$ for 2.6~pix 
FWHM). Immediately before or after every object spectrum, exposures of a ThAr lamp were taken to calibrate in wavelength. The 
internal precision of the arc lamp calibrations is better than $\pm 1.0$~km~s$^{-1}$.


%%%%% TABLA 5

\setcounter{table}{4}
\begin{table}[!t]
\vspace{0.1cm}
\centering
\setlength{\tabnotewidth}{0.99\columnwidth}
\tablecols{4}
\caption{New Planetary nebulae in M31 and M33} 
\label{tab_RLH}
\begin{tabular}{clcc}
\toprule
Galaxy  & \multicolumn{1}{c}{Object} & $\alpha (2000)$ & $\delta (2000)$ \\
\midrule
M31 & f08n04    & 00 49 50~~  & 42 31 40 \\
M31 & f08n05    & 00 49 32~~  & 42 37 38 \\
M31 & f08n08    & 00 50 13~~  & 42 29 48 \\
M31 & f08n09    & 00 48 48~~  & 42 51 36 \\
M31 & f08n10    & 00 47 54~~  & 42 14 58 \\
M31 & f15n12002 & 00 47 46.8  & 42 12 15 \\
M31 & f29n2065  & 00 33 41.1  & 39 31 51 \\
M31 & f29n9178  & 00 37 21.1  & 39 50 51 \\
M31 & f32n1     & 00 49 55~~  & 38 32 49 \\
M33 & NewPN     & 01 32 56~~  & 30 25 56 \\
\bottomrule
\tabnotetext{}{The objects in M31 are from \citet{richeretal2004}.}
\end{tabular}
\vspace{0.2cm}
\end{table}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%5


All spectra were of 30 minutes duration. Depending upon the resulting signal-to-noise, up to four spectra were acquired, occasionally 
during more than one observing run. With very few exceptions (PN24 and PN25 in M32), the spectrometer slit was always oriented 
north-south over the object(s) of interest.  


%%%%% FIGURA 1

\begin{figure}[!t]
\centerline{\includegraphics[width=2.6cm,height=5.6cm]{mricherfig1a}%
\hspace{0.1cm}%
\includegraphics[width=2.6cm,height=5.6cm]{mricherfig1b}%
\hspace{0.1cm}%
\includegraphics[width=2.6cm,height=5.6cm]{mricherfig1c}}
\caption{The left panel presents the raw two-dimensional spectrum for PN24 and PN25 in M32 (east is up, bluer 
wavelengths to the left). The continuous emission below them (to the west) is from M32's nuclear region. The 
planetary nebulae are sufficiently close together that their emission is merged into a single teardrop-shaped 
profile. The middle panel presents the same spectrum for PN24 and PN25 once M32's continuous emission had been 
filtered out. For comparison, the right panel presents the two-dimensional spectrum for PN26, PN23, and PN21 
in M32 (ordered north to south; north is up, bluer wavelengths to the left) at the same spatial scale and taken 
immediately prior to the spectrum of PN24 and PN25 (continuous emission from M32 is again visible). The 
two-dimensional (spatially-merged) spectrum of PN24 and PN25 is clearly more complex than the spectra of PN26, 
PN23, or PN21. PN25 is to the east (above) of PN24, has a more blueshifted radial velocity, and a narrower line 
profile (see Table~2), the two effects explaining the tilted teardrop shape of the combined profile. The 
``individual'' profiles for PN24 and PN25 were obtained by splitting the combined emission at the spatial centre.}  
\label{fig_m32pn24pn25}
\vspace{0.3cm}
\end{figure}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%


Table~2 presents our entire sample of extragalactic planetary nebulae. In total, we observed 211 extragalactic planetary nebulae in 
11 Local Group galaxies. More than half of the sample is drawn from M31 (137 objects), with M33 providing the second largest sample 
(33 objects). The remaining galactic hosts are dwarfs and their planetary nebula populations are smaller: one planetary nebula was 
observed in each of Fornax, Leo A, and Sextans A, 2 in NGC 147, 3 in Sagittarius, 5 in NGC 185, 6 in NGC 6822, 9 in NGC 205, and 13 
in M32. Most of the objects we observed are within two magnitudes of the peak of the PNLF, though we did try to observe fainter objects 
if low-resolution spectra existed in the literature. Table~3 presents our few H$\alpha$ spectra. In Table~4, we present observations 
of three objects whose classifications as planetary nebulae are dubious. 

The object names we adopt in Tables~\ref{tab_o3}--\ref{tab_cHII} come from the following sources: Leo A and Sextans A from 
\citet{jacobylesser1981}; Fornax from \citet{danzigeretal1978}; M31 from \citet{fordjacoby1978}, \citet{lawrieford1982}, 
\citet{noltheniusford1987}, \citet{ciardulloetal1989b}, Richer, Lee, \& Hwang (2004), and \citet{merrettetal2006}; M32 from 
\citet{fordjenner1975} and \citet{ford1983}; M33 from \citet{magrinietal2000}; NGC 147 from \citet{corradietal2005}; NGC 185 
from Ford, Jacoby, \& Jenner (1977); NGC 205 from Ford, Jenner, \& Epps (1973), \citet{ford1978}, and \citet{ciardulloetal1989b}; 
NGC 3109 from \citet{penaetal2007}; NGC 6822 from \citet{killendufour1982} and \citet{leisyetal2005}; and Sagittarius from 
\citet{ackeretal1992}. The names follow strict historical precedent, except for NGC 147, NGC 3109 
\citep[we do not use][]{richermccall1992}, and perhaps some objects in M31 from \citet{noltheniusford1987} whose identifications 
are taken from \citet{merrettetal2006}. Coordinates for the objects from \citet{richeretal2004} and a new planetary nebula 
candidate that we discovered in M33 are given in Table~5. 

All of the spectra were reduced using the {\sc Specred} package of the Image Reduction and Analysis Facility\footnote{IRAF is distributed 
by the National Optical Astronomical Observatories, which is operated by the Associated Universities for Research in Astronomy, Inc., 
under contract to the National Science Foundation.} (IRAF) following Massey, Valdes, \& Barnes (1992). We edited each spectrum for 
the presence of cosmic rays. We then extracted the source spectra and used these apertures to extract ThAr spectra from the lamp 
spectra. The latter were used to calibrate in wavelength. If more than one object spectrum was obtained, they were co-added after 
being calibrated in wavelength. If they did not coincide exactly in wavelength, likely the result of centering differently or low 
signal-to-noise (S/N), they were shifted to a common wavelength and then co-added. Note that shifting the spectra before co-adding 
minimizes the eventual line width that we measure. We did not calibrate in flux. 

Except for PN24 and PN25 in M32, all of the objects were observed as spatially distinct sources. However, there were occasions when 
multiple objects fell within the spectrometer slit, particularly for M31 and M32 (see Figure~\ref{fig_m32pn24pn25}, right panel). 
PN24 and PN25 in M32 required special treatment, since their images were not clearly resolved spatially by the spectrometer (the 
spectrometer slit was oriented east-west in the hope of better separating them). Fortunately, both their radial velocities and line 
widths are distinct, which helps separating their spectra. Figure~\ref{fig_m32pn24pn25} presents the two-dimensional spectrum of PN24 
and PN25 (both raw and filtered so as to remove M32's continuous spectrum) and compares it with the two-dimensional spectrum of PN26, 
PN23, and PN21 (in M32) taken immediately before. It is clear that the two-dimensional spectrum of PN24 and PN25 is more complicated 
in the spatial direction (vertical in Figure~\ref{fig_m32pn24pn25}) than those of the other PNe. The ``individual'' profiles for 
PN24 and PN25 were obtained by splitting the combined profile at the spatial centre since the two PNe are similarly bright 
\citep{ciardulloetal1989b}. Table~2 presents the analysis of both the combined and split profiles for PN24 and PN25. 

%\vspace{0.2cm}

\section{Data Analysis} 
\label{analysis}

The line profiles of extragalactic planetary nebulae usually cannot be distinguished statistically from a Gaussian shape because 
of their limited S/N \citep[e.g.,][]{dopitaetal1985, dopitaetal1988, arnaboldietal2008}. We analyzed the one-dimensional line 
profiles with a locally-implemented software package (INTENS) (McCall, Rybski, \& Shields 1985) to determine the radial velocity, 
flux, and profile width (FWHM; full width at half maximum intensity) as well as the uncertainties ($1\sigma$) in these parameters. 
INTENS fits the emission line profile with a sampled Gaussian function and models the continuum as a straight line. Thus, this 
analysis assumes that the lines have a Gaussian shape and that they are superposed on a flat continuum. 
Figures~\ref{fig_line_prof_gallery1}--\ref{fig_line_prof_gallery3} present examples of the line profiles. Excepting the planetary 
nebulae in the Fornax and Sagittarius dwarf spheroidals, the line profiles in Figures~\ref{fig_line_prof_gallery1}--\ref{fig_line_prof_gallery3} 
do not deviate significantly from a Gaussian shape, even though they are among our profiles with the highest S/N. For the 
[\ion{O}{3}]$\lambda$5007 observations, we typically fit a 10~\AA\ spectral interval more or less centered on the emission line, 
though as little as 6~\AA\ was used in some cases to avoid cosmic rays. For the H$\alpha$ observations, a 15~\AA\ interval was used. 
For the observations of StWr 2-21 and Wray 16-423 in the light of H$\alpha$, the \ion{He}{2}~$\lambda$6560 line is also present, 
so we fit both lines simultaneously, but assuming  that the widths of both lines are identical. 


%%%%% FIGURA 2

\begin{figure*}[!t]
\centerline{\includegraphics[width=0.98\columnwidth]{mricherfigura2a}%
\hspace{\columnsep}%
\includegraphics[width=0.98\columnwidth]{mricherfigura2b}}
\centerline{\includegraphics[width=0.98\columnwidth]{mricherfigura2c}%
\hspace{\columnsep}%
\includegraphics[width=0.98\columnwidth]{mricherfigura2d}}
\centerline{\includegraphics[width=0.98\columnwidth]{mricherfigura2e}%
\hspace{\columnsep}% 
\includegraphics[width=0.98\columnwidth]{mricherfigura2f}}
\caption{This and the following two figures present a gallery of representative line profiles for extragalactic 
planetary nebulae. Here, the line profiles for planetary nebulae in four dwarf spheroidals are shown. The light-colored 
symbols are the data and the solid line is the Gaussian fit. In all cases, a 10~\AA\ spectral interval is plotted. 
The line profiles for the planetary nebulae in Fornax and Sagittarius are those with the highest S/N. Even so, 
deviations from a Gaussian profile are small, though real (8--11\% of the total flux). For the remaining objects, 
the deviations are usually insignificant.}
\label{fig_line_prof_gallery1}
\vspace{0.6cm}
\end{figure*}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%


%%%%% FIGURA 3

\begin{figure*}[!t]
\centerline{\includegraphics[width=0.98\columnwidth]{mricherfigura3a}%
\hspace{\columnsep}%
\includegraphics[width=0.98\columnwidth]{mricherfigura3b}}
\centerline{\includegraphics[width=0.98\columnwidth]{mricherfigura3c}%
\hspace{\columnsep}% 
\includegraphics[width=0.98\columnwidth]{mricherfigura3d}}
\centerline{\includegraphics[width=0.98\columnwidth]{mricherfigura3e}%
\hspace{\columnsep}%
\includegraphics[width=0.98\columnwidth]{mricherfigura3f}}
\caption{The line profiles are shown for planetary nebulae in NGC 205, M32, the dwarf irregular galaxies 
Leo A, Sex A, and NGC 6822, and the spiral galaxy M33. Deviations of the data about the Gaussian fit are 
insignificant, even though these are among the profiles with the best S/N in these galaxies. See 
Figure~\ref{fig_line_prof_gallery1} for further details.}
\label{fig_line_prof_gallery2}
\vspace{0.4cm}
\end{figure*}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%


%%%%%% FIGURA 4

\begin{figure*}[!t]
\centerline{\includegraphics[width=0.98\columnwidth]{mricherfigura4a}%
\hspace{\columnsep}% 
\includegraphics[width=0.98\columnwidth]{mricherfigura4b}}
\centerline{\includegraphics[width=0.98\columnwidth]{mricherfigura4c}%
\hspace{\columnsep}%  
\includegraphics[width=0.98\columnwidth]{mricherfigura4d}} 
\caption{The line profiles for four planetary nebulae in M31 are shown. PN 30 and PN 32 belong to the 
bulge, M2404 to the disk, and M2496 to the halo. Deviations of the data about the Gaussian fit are 
insignificant, even though these are among the profiles with the best S/N in M31 (PN 30 excepted). See 
Figure~\ref{fig_line_prof_gallery1} for further details.}
\label{fig_line_prof_gallery3}
\vspace{0.35cm}
\end{figure*}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%


For each object we observed, Tables 2--4 present the flux, the observed line width, the heliocentric radial velocity (from IRAF's 
{\sc rvcorrect}), \emph{half} of the intrinsic line width (see below, equation~\ref{eq_sigma}), and the corresponding uncertainties in 
all of these quantities. The uncertainties are formal, one-sigma uncertainties and pertain to the final (sometimes summed) spectra.

As already noted (\S~\ref{observations}), we did not attempt a flux calibration. The vast majority of the objects in our catalogue 
(Table~5 contains the few exceptions) already have published photometry that is undoubtedly more precise that our spectroscopic 
fluxes would have been. In practice, our fluxes provided a guide as to the need for additional observations. We found that the 
accumulation of 4000--5000 counts was sufficient to provide adequate line profiles for analysis, provided that the line profiles 
were not too wide. These fluxes allow the reader to judge the quality of the line profiles independently of the uncertainties attached 
to the line widths and central wavelengths.  

The radial velocities and the observed line widths in Tables~\ref{tab_o3}--\ref{tab_cHII} are obtained as a result of fitting a 
Gaussian function to the line profile. Their \emph{formal} uncertainties will depend upon the S/N and shape of the line profile. 
Given line shapes that are nearly Gaussian and reasonable S/N, we commonly obtain formal uncertainties in the line widths and 
radial velocities that are substantially smaller than the instrument's absolute internal precision (\S~\ref{observations}). While 
these formal uncertainties are relevant for the line widths (observed and intrinsic), it is no surprise that the uncertainties 
in the radial velocities are dominated by systematic calibration issues (\S~\ref{radial_velocities}). 

To compute the intrinsic line widths, the observed line widths are corrected for instrumental, Doppler/thermal, and fine structure 
broadening, supposing that all add in quadrature, i.e.,
\begin{equation}
\sigma^2_\mathrm{obs} = \sigma^2_\mathrm{true} + \sigma^2_\mathrm{inst} + \sigma^2_\mathrm{th} + \sigma^2_\mathrm{fs}\,,
\label{eq_sigma}
\end{equation}
\noindent where $\sigma_\mathrm{true}$ is the intrinsic line width resulting from the kinematics of the planetary nebula while 
$\sigma_\mathrm{inst}$, $\sigma_\mathrm{th}$, and $\sigma_\mathrm{fs}$ represent the instrumental, thermal, and fine structure 
broadening, respectively. The instrumental profile is very nearly Gaussian with the pixel binning used and has a measured FWHM 
of 2.5--2.7 pixels, so we adopted a FWHM of 2.6 pixels for all objects ($\sim 11$~km~s$^{-1}$ FWHM). We compute the thermal 
broadening from the usual formula \citep[][equation~2-243]{lang1980}, adopting rest wavelengths of 6562.83~\AA\ and 5006.85~\AA\ 
for H$\alpha$ and [\ion{O}{3}]$\lambda 5007$, respectively, assuming an electron temperature of $10^4$~K and zero turbulent 
velocity. The only exceptions were the planetary nebulae in the Fornax and Sagittarius dwarf spheroidal galaxies, for which 
the electron temperatures were adopted from the literature \citep{dudziaketal2000, zijlstraetal2006, kniazevetal2007}. The 
resulting thermal broadening (FWHM) at $10^4$~K amounts to 0.47~\AA\ (21.4~km~s$^{-1}$) and 0.089~\AA\ (5.3~km~s$^{-1}$) for 
H$\alpha$ and [\ion{O}{3}]$\lambda 5007$, respectively. The fine structure broadening \citep{meaburn1970}, $\sigma_\mathrm{fs}$, 
was taken to be 3.199~km~s$^{-1}$ (FWHM 7.53~km~s$^{-1}$) for H$\alpha$ and zero for [\ion{O}{3}]$\lambda 5007$ (Garc\'ia-D\'iaz 
et al. 2008). 

For a homogeneous, spherical, thin shell that fits entirely within the spectrometer slit, the resulting corrected line width,
\begin{equation}
\Delta V = 2.3556\sigma_\mathrm{true}\,, 
\end{equation}
\noindent is twice the expansion velocity.  Only StWr 2-21 in the Sagittarius dwarf spheroidal is larger than our  slit 
\citep[][]{zijlstraetal2006}. Departures from these assumptions in real objects affect the interpretation of $\Delta V$ 
(Sch\"onberner et al. 2005a). The ionized shells of planetary nebulae are neither infinitely thin, uniformly expanding, 
nor perfectly spherically symmetric. Furthermore, velocity gradients within the ionized shell are relatively common 
\citep[see][for early examples]{wilson1950}. In practice, it is clear that $\Delta V$ will be approximately twice the 
typical luminosity-weighted projected velocity at which the mass of the $\mathrm O^{2+}$ zone is flowing away from the 
central star. The pattern velocity of the shock or ionization front that corresponds to the expansion velocity is substantially 
larger  (Marten, Gesicki, \& Szczerba 1993; Steffen et al. 1997; Sch\"onberner et al. 2005a). Given that, we adopt 
\begin{equation}
\Delta V_{0.5} = 0.5\Delta V = 1.1778\sigma_\mathrm{true}\,, 
\end{equation}
\noindent as our measure of the kinematics of the matter in the $\mathrm O^{2+}$ zone. It is this line width that is 
tabulated in Tables~\ref{tab_o3}--\ref{tab_cHII}. Since $\Delta V_{0.5}$ is obtained by fitting a Gaussian function, 
the line width at any other intensity may be derived from it. \citet{richeretal2009} further discuss the limitations 
of this analysis.


\section{Results}
\label{results}

\subsection{Line Profiles}

As expected, Figures~\ref{fig_line_prof_gallery1}--\ref{fig_line_prof_gallery3} demonstrate that the spatially-integrated 
line profiles for bright extragalactic planetary nebulae are Gaussian in shape, or nearly so, in agreement with previous 
results \citep{dopitaetal1985, dopitaetal1988, zijlstraetal2006, arnaboldietal2008}. Our deepest profiles, however, show 
some additional structure. Based upon observations of bright, compact planetary nebulae in the Milky Way bulge, \citet{richeretal2009} 
found that the Gaussian component represented more than 75\% of the [\ion{O}{3}]$\lambda 5007$ emission in 89\% of all cases. 
Therefore, it is clear that the Gaussian component is an adequate representation of most of the line emission. \citet{richeretal2009} 
also found that the line width of the Gaussian component was recovered reliably at the flux levels typical of bright 
extragalactic planetary nebulae. 


%%%%% FIGURA 5

\begin{figure}[!t]
\centering
\includegraphics[width=0.98\columnwidth]{mricherfig5}
\caption{We compare the line widths measured in the lines of H$\alpha$ and [\ion{O}{3}]$\lambda 5007$. 
The solid line indicates the locus of identical line widths. The error bars show the formal uncertainty 
in line widths from the INTENS fit, which is smaller than the symbol for the planetary nebulae in Fornax 
and Sagittarius. The intrinsic widths of the two lines are similar, as is also found for planetary nebulae 
in the Milky Way bulge \citep{richeretal2009}.}
\label{fig_dv_o3_ha}
\vspace{0.4cm}
\end{figure}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%


\subsection{Line Widths: H$\alpha$ Versus [\ion{O}{3}]$\lambda 5007$}

Figure~\ref{fig_dv_o3_ha} compares the H$\alpha$ and [\ion{O}{3}]$\lambda 5007$ line widths for those few objects for which both 
lines were observed. As already noted by \citet{richeretal2009}, the line widths for the two lines are similar in bright planetary 
nebulae in the Milky Way bulge that were selected to mimic samples of bright extragalactic planetary nebulae in environments without 
star formation. Taken with the result previously presented, the line width measured from the [\ion{O}{3}]$\lambda 5007$ line should 
be an adequate and reliable description of the kinematics of the entire ionized shell in bright extragalactic planetary nebulae. 


%%%%% FIGURA 6

\begin{figure}[!t]
\centering
 \includegraphics[width=0.98\columnwidth]{mricherfig6}
\caption{We compare our radial velocities with those measured by \citet[][M06]{merrettetal2006} 
for planetary nebulae in M31, M32, and NGC 205. The solid line indicates the locus of identical 
radial velocities. Our velocities are offset slightly, by --3.3~km~s$^{-1}$.}
\label{fig_compare_merrett}
\vspace{0.3cm}
\end{figure}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%\vspace{0.3cm}

\subsection{Radial Velocities}
\label{radial_velocities}

Although we made no effort to obtain precise absolute radial velocities, i.e., we observed no radial velocity standards, our 
heliocentric radial velocities turn out to be reasonably precise. In computing the radial velocities, we adopt the same rest 
wavelengths as for the analysis of thermal broadening (\S~\ref{analysis}). The largest sample with which we can compare our 
radial velocities is that reported by \citet[][M06]{merrettetal2006} with which we have 136 objects in common in M31, M32, and 
NGC 205. (Note that M06 adopt their absolute velocity scale from Halliday et al. 2006). Figure~\ref{fig_compare_merrett} presents 
the correlation between the heliocentric radial velocities for the two data sets. Clearly, the correlation is very good, with 
the exception of five objects (PN1, PN12, PN23, PN69, and PN190 in M31). Excluding these objects, a linear least squares fit finds
\begin{equation}
V_\mathrm{rad} = (1.005 \pm 0.010)V_\mathrm{M06} + (-3.3\pm 3.2)~\mathrm{km~s^{-1}}\,.
\end{equation}
\noindent Thus, our heliocentric radial velocities differ only marginally from those of  M06, with a possible offset of only 
--3.3~km~s$^{-1}$. The dispersion about this relation is 16.7~km~s$^{-1}$. Considering that M06 claim an intrinsic dispersion 
of approximately 14~km~s$^{-1}$ for their measurements, our radial velocities should then have an intrinsic dispersion of about 
9~km~s$^{-1}$. 


%%%%% FIGURA 7

\begin{figure}[!t]
\centering
\includegraphics[width=0.98\columnwidth]{mricherfig7}
\caption{We compare our radial velocities with those measured by Ciardullo et al. (2004) for planetary 
nebulae in M33. The solid line indicates the locus of identical radial velocities. Our velocities 
are offset, by --13.8~km~s$^{-1}$.}
\label{fig_compare_ciardullo}
\vspace{0.3cm}
\end{figure}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%


We can also compare our heliocentric radial velocities for planetary nebulae in M33 with those of \citet[][C04]{ciardulloetal2004}. 
Figure~\ref{fig_compare_ciardullo} presents the correlation for the 29 objects common to the two data sets, which is again 
very good, with M074 being the only deviant data point. A linear least squares fit finds 
\begin{equation}
V_\mathrm{rad} = (0.956\pm 0.027)V_\mathrm{C04} + (-13.8\pm 4.7)~\mathrm{km~s^{-1}}\,.
\end{equation}
\noindent  Again, there is only a marginal difference, apart from an offset of --13.8~km~s$^{-1}$. The dispersion about the 
above relation is 8.0~km~s$^{-1}$. From Table~5 in \citet{ciardulloetal2004}, their typical uncertainty should be about 
5.5~km~s$^{-1}$, implying that our radial velocities should have an intrinsic dispersion of about 5.8~km~s$^{-1}$. 

It is no coincidence that the intrinsic dispersion in our radial velocities is slightly less than the FWHM (11 km~s$^{-1}$) 
we measure for the arc lamp. Objects are centered in the slit via the spectrometer's imaging mode using short double exposures 
(sky and then slit) before the spectroscopic exposure.  While this guarantees that the object is centered in the slit during 
the acquisition exposure, small differential guiding errors between the acquisition and spectrosocpic exposures can result 
in it being displaced from the centre of the slit towards one side during the spectroscopic exposure. Since the spectrometer 
resolves the slit used for these observations (\S~\ref{observations}), the resulting radial velocities will be dispersed over 
a range somewhat less than the FWHM of the arc lines. 

We find slightly different offsets with respect to  M06 and C04. This either reflects differences between their velocity scales 
or slight systematic changes in our radial velocity zero points from one observing run to the next. Given that neither we nor 
C04, M06, or \citet{hallidayetal2006} observed any radial velocity standards, the small offsets noted are not surprising. We 
therefore conclude that our radial velocities have an absolute precision on the order of 10~km~s$^{-1}$. 


\subsection{Line Width Versus Stellar Population}

A perusal of Tables 2--4 reveals that the typical line widths, $\Delta V_{0.5}$, span a limited range in all galaxies. Typically, 
$\Delta V_{0.5}$ is between 13 and 24~km~s$^{-1}$, though the total range extends from 6 to 30~km~s$^{-1}$. Considering other similar 
data in the literature, the foregoing changes relatively little, though the example of SMP83 in the LMC demonstrates that occasionally 
larger line widths may be found among planetary nebulae within 2.5~mag of the peak of the PNLF \citep{dopitaetal1985, dopitaetal1988, 
zijlstraetal2006, arnaboldietal2008}.


%%%%% FIGURA 8

\begin{figure}[!t]
\centering
\includegraphics[width=0.96\columnwidth]{mricherfig8}
\caption{We compare the average [\ion{O}{3}]$\lambda$5007 line width from Table~\ref{tab_o3}, 
$\Delta V_{0.5}$, found for the planetary nebulae in different galaxies. The ``error bars'' 
indicate the standard deviations of the line width distributions. The number in parentheses 
indicates the number of planetary nebulae observed in each galaxy. Clearly, the average line 
width does not vary much among different galaxies. The data for the Magellanic Clouds are taken 
from \citet{dopitaetal1985, dopitaetal1988} for planetary nebulae within 2.5~mag of the PNLF 
peak. The data for the Virgo Cluster are taken from \citet{arnaboldietal2008}.}
\label{fig_line_width}
\vspace{0.15cm}
\end{figure}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%


Figure~\ref{fig_line_width} presents the average line width, $\Delta V_{0.5}$, observed for the planetary nebula populations 
in each of the galaxies in our sample. The ``error bars'' indicate the standard deviation of the $\Delta V_{0.5}$ distribution. 
In this figure, the star-forming systems are on the left while those without active, ongoing star formation are on the right. 
M31 is a mixed system in this diagram, with ongoing star formation in its disc, but with the bulge having ceased this activity 
long ago. The data points for the Magellanic Clouds are taken from the data published by \citet{dopitaetal1985, dopitaetal1988} 
for planetary nebulae within 2.5~mag of the PNLF peak, but using the same line width definition as for our data. The data point 
for the Virgo Cluster is based upon the data published by \citet{arnaboldietal2008} for its \emph{intracluster} planetary nebulae. 
Our only modification of their results was to correct for thermal broadening as we did for our data. Obviously, the progenitor 
stellar population for these intracluster planetary nebulae is unknown. 


%%%%% FIGURA 9

\begin{figure}[!t]
\centering
\includegraphics[width=0.95\columnwidth]{mricherfig9}
\caption{The planetary nebulae observed in M31 are shown overplotted on a DSS image of M31, M32, 
and NGC 205. The bar is one degree in length. North is up and east is to the left.}
\label{fig_M31_pne}
\vspace{0.2cm}
\end{figure}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%


%%%%% FIGURA 10

\begin{figure}[!t]
\centering
\includegraphics[width=0.95\columnwidth]{mricherfig10}
\caption{For the planetary nebulae in M31, we plot the average of $\Delta V_{0.5}$ for different samples 
as a function of distance from the nucleus. The large symbols denote averages for the bulge, disc, and 
halo planetary nebulae (as defined in the text). The numbers next to the labels indicate the number of 
objects in each sample. The vertical error bars indicate the standard deviation within each group while 
the horizontal error bars denote the ratial extent. The small symbols show the local average $\Delta V_{0.5}$ 
for bulge and disc planetary nebulae. There is a clear tendency towards lower line widths at greater 
radial distances.}
\label{fig_M31_radial}
\vspace{0.2cm}
\end{figure}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%


The average line width ($\Delta V_{0.5}$) falls in a narrow range in Figure~\ref{fig_line_width}. For all galaxies with at 
least three planetary nebulae observed, the average $\Delta V_{0.5}$ falls in the range of 14--21~km~s$^{-1}$. There is no 
obvious difference between galaxies with and without ongoing star formation. This velocity range also includes the average 
line width (16.3~km~s$^{-1}$) for intra\-cluster planetary nebulae in the Virgo cluster core \citep{arnaboldietal2008}. 

Likewise, the range of line widths ($\Delta V_{0.5}$) is also similar among galaxies. There is a tendency to find a slightly 
larger range of line widths in the dwarf galaxies compared to M31 and M33. If this tendency is statistically significant, it 
occurs for both dwarf irregulars and dwarf spheroidals, so it would appear to be due to the metallicity rather than the age 
of the progenitor stars. The line widths for the intracluster planetary nebulae in the Virgo cluster have a very narrow 
distribution, perhaps a result of the effects studied by \citet{villaveretal2006}.


\subsection{M31}

We observed planetary nebulae in several stellar subsystems in M31 (bulge, disk, halo) as may be appreciated from Figure~\ref{fig_M31_pne}. 
For the purposes of the analysis here, we assign planetary nebulae to a given subsystem based upon their position within the 
galaxy alone. This will clearly not be perfect, but adopting a more complex scheme, such as including kinematic information, 
would not necessarily provide a perfect solution either. We designate as halo objects the nine planetary nebulae lying more 
than $0.5^{\circ}$ from the major axis, since this implies an inclination-corrected disc radius $> 2.2^{\circ}$, or $> 30.3$~kpc 
for our adopted distance of 789~kpc \citep{leeetal2003}. Note that these nine planetary nebulae all have inclination-corrected, 
projected disc radii in excess of $3.2^{\circ}$/44~kpc (adopting the scheme from Huchra, Brodie, \& Kent 1991), so it is very 
unlikely that they are disc objects. We designate as bulge planetary nebulae the 80 objects within the effective radius of the bulge 
\citep[$0.17^{\circ}$:][]{walterboskennicutt1988}. The remaining 48 planetary nebulae are assigned to the disk. Note that M32-PN29 
has a radial velocity indicating that it belongs to M31 (the disk in our scheme). Our bulge-disc division will produce a bulge 
sample that is truly dominated by bulge planetary nebulae, but the disc sample will be contaminated by bulge objects near the 
cut-off radius. 

While Figure~\ref{fig_line_width} demonstrates that, to first order, the typical outflow velocity is not especially sensitive 
to either the metallicity or age of the progenitor stellar population, differences are noticeable within M31. In Figure~\ref{fig_M31_radial}, 
we plot the average outflow velocity for the bulge, inner disc ($< 1^{\circ}$), outer disc ($> 1^{\circ}$), and halo samples as 
well as a local average for bulge and disc planetary nebulae. Clearly, the line width, $\Delta V_{0.5}$, is lower for planetary 
nebulae at greater distances from the nucleus, though the inner disc and bulge have similar values. On the other hand, the width of the 
velocity distribution does not vary with nuclear distance. 

The robustness of this trend can be tested via statistical tests. The simplest comparison is to consider the distribution of 
line widths for planetary nebulae in the bulge and disk. Applying the U-test to these subsamples \citep[][]{walljenkins2003},
 there is only a 2.4\% probability of obtaining the two line width distributions by chance from a single progenitor population. 
If the disk subsample is restricted to those objects at separations greater than $1^{\circ}$ from the nucleus, thereby minimizing the 
contamination of the disc sample by bulge objects, the probability of obtaining the two distributions by chance from a single 
parent population drops to 0.5\%. Therefore, the trend of lower average line width ($\Delta V_{0.5}$) at greater radial distances 
is statistically significant. 


%%%%% FIGURA 11

\begin{figure*}[!t]
\centering
\includegraphics[width=12.8cm]{mricherfig11}
\caption{We plot the [\ion{O}{3}]$\lambda 5007$ line width as a function of the oxygen abundance for 
the planetary nebulae with low resolution spectra. The symbols for galaxies without star formation 
are in bold or filled while the symbols for galaxies with ongoing star formation are light and unfilled. 
Bright and faint planetary nebulae in the Magellanic Clouds are distinguished by large and small symbols, 
respectively. For M31, the planetary nebulae come overwhelmingly from the bulge. Galactic systems with 
and without star formation cover the abundance range from $7.9 < 12+\log(\mathrm O/\mathrm H) < 8.5$, but 
planetary nebulae from the bulge of M31 dominate higher abundances. There is no strong variation in line 
width with abundance or between galactic systems with and without star formation. The oxygen abundances are 
taken from Richer \& McCall (2008) and Magrini, Stanghellini, \& Villaver (2009); the former adopting data 
from Jacoby \& Ford (1986), Aller et al. (1987), Barlow (1987), Monk, Barlow, \& Clegg (1988), Wood et al. 
(1987), Dopita et al. (1988), Meatheringham, Dopita, \& Morgan (1988), Henry, Liebert, \& Boroson (1989), 
Meatheringham \& Dopita (1991a,b), Dopita \& Meatheringham (1991), Vassiliadis et al. (1992), Jacoby \& Kaler 
(1993), Leisy \& Dennefeld (1996), Walsh et al. (1997), Jacoby \& Ciardullo (1999), Richer, Stasi\'nska, \& 
McCall (1999), Roth et al. (2004), Kniazev et al. (2005), Magrini et al. (2005), van Zee, Skillman, \& Haynes 
(2006), Zijlstra et al. (2006), Gon\c calves et al. (2007), Kniazev et al (2007), and Richer \& McCall (2007, 2008).}
\label{fig_dv_o3abun}
\vspace{0.31cm}
\end{figure*}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%


%%%%%% FIGURA 12

\begin{figure*}[!t]
\centering
\includegraphics[width=12.8cm]{mricherfig12}
\caption{We plot the [\ion{O}{3}]$\lambda 5007$ line width as a function of the absolute [\ion{O}{3}]$\lambda 5007$ 
magnitude, $M_{5007}$, for those objects with appropriate data from the literature (for $M_{5007}$ references, see 
\S~\ref{observations} for photometry and Figure~\ref{fig_dv_o3abun} for spectroscopy). The distances are adopted from 
\citet{richermccall1995} and \citet{leeetal2003}, except for M33 and NGC 147, for which we adopt distance moduli from 
\citet{mcconnachieetal2005} since their distances (tip of red giant branch) for M31, NGC 185, and NGC 205 are consistent 
with those we adopt. The symbols follow the same scheme as in Figure~\ref{fig_dv_o3abun}. Note, however, that this 
figure includes many planetary nebulae from M31's disk. As in Figure~\ref{fig_dv_o3abun}, no strong trend with line 
width is seen. The only systematic effect is an increased dispersion for $M_{5007} > -2$~mag.}
\label{fig_dv_M5007}
\vspace{0.4cm}
\end{figure*}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%


%%%%% FIGURA 13

\begin{figure*}[!t]
\centering
\includegraphics[width=12.8cm]{mricherfig13}
\caption{We plot the [\ion{O}{3}]$\lambda 5007$ line width as a function of the $I(5007)/I(\mathrm H\beta)$ 
ratio for the planetary nebulae with low resolution spectra (see the literature cited in Figure~\ref{fig_dv_o3abun}). 
The symbols follow the same scheme as in Figure~\ref{fig_dv_o3abun}. Here, most of the M31 planetary nebulae 
are from its bulge. In part, the higher oxygen abundances for the planetary nebulae in M31's bulge allow them 
to achieve higher $I(5007)/I(\mathrm H\beta)$ ratios than those for planetary nebulae elsewhere. However, the planetary 
nebulae in M32 and the dwarf spheroidals tend to have systematically larger ratios than their counterparts in 
the dwarf irregulars, even though they have similar oxygen abundances, so nebular structure or the distribution 
of central star temperatures also likely play a role in elevating the $I(5007)/I(\mathrm H\beta)$ ratios for 
planetary nebulae in systems without star formation.}
\label{fig_dv_o3hbrat}
\vspace{0.3cm}
\end{figure*}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%


%%%%% FIGURA 14

\begin{figure*}[!t]
\centering
\includegraphics[width=12.8cm]{mricherfig14}
\caption{We plot the [\ion{O}{3}]$\lambda 5007$ line width as a function of the H$\beta$ luminosity of the 
planetary nebula for those objects with low resolution spectra from the literature. The luminosities are 
based upon the distances and photometry from the references given in Figure~\ref{fig_dv_M5007} and \S~2, 
respectively, and the [\ion{O}{3}]$\lambda 5007/\mathrm H\beta$ ratios from the literature cited in 
Figure~\ref{fig_dv_o3abun}. The symbols follow the same scheme as in Figure~\ref{fig_dv_o3abun}. Again, 
most of the M31 planetary nebulae are from its bulge. At the brightest H$\beta$ luminosities there is a lack 
of the largest line widths. Conversely, at the faintest H$\beta$ luminosities, the opposite occurs and there 
is a lack of the smallest line widths.}
\label{fig_dv_hblum}
\vspace{0.4cm}
\end{figure*}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%5

%\vspace{0.25cm}

\section{Discussion}
\label{discussion}

Figure~\ref{fig_dv_o3_ha} indicates that the line widths in the lines of H$\alpha$ and [\ion{O}{3}]$\lambda 5007$ are similar, 
a result found for planetary nebulae in the Milky Way bulge \citep{richeretal2009}. Hence, the line width observed for the 
brighter [\ion{O}{3}]$\lambda 5007$ line is a reasonable approximation of the line width for the entire ionized nebular shell. 
In all likelihood, this result arises because the intrinsically brightest planetary nebulae in the [\ion{O}{3}]$\lambda 5007$ 
line, such as those observed here, probably have O$^{2+}$ zones that occupy a large fraction of the volume of the ionized shell. 

\vspace{0.05cm}

Figure~\ref{fig_dv_o3_ha} also implies that, for planetary nebulae that are intrinsically bright in [\ion{O}{3}]$\lambda 5007$, 
ionization stratification \citep[e.g.,][]{wilson1950} does \emph{not} strongly bias the width of the [\ion{O}{3}]$\lambda 5007$ 
line. Ionization stratification might explain the trend of systematically lower [\ion{O}{3}]$\lambda 5007$ line widths at small 
H$\alpha$ line widths, but even this effect is small. Therefore, in spite of ionization stratification, for it undoubtedly must 
occur, the [\ion{O}{3}]$\lambda 5007$ line width is a good estimator of the line width for the entire ionized shell, as measured 
by H$\alpha$. The large volume of the O$^{2+}$ zone plays an important role in establishing this result and is a product of our 
sample selection (high [\ion{O}{3}]$\lambda 5007$ luminosity). For objects in other evolutionary phases, our result may not hold, 
as is commonly found in highly evolved objects where ionization stratification is regularly seen (e.g., Meaburn, L\'opez, \& 
Richer 2008). 

\vspace{0.05cm}

The individual planetary nebulae in Figure~\ref{fig_dv_o3_ha} arise from galaxies both with and without ongoing star formation. 
Although the sample is small, there is no obvious indication that the relation between H$\alpha$ and [\ion{O}{3}]$\lambda 5007$ 
line widths differs between galaxies with and without ongoing star formation. Therefore, it appears that the [\ion{O}{3}]$\lambda 5007$ 
line width is an equally good estimate of the line width for the entire ionized shell in the brightest planetary nebulae in all 
galaxies.

\vspace{0.05cm}

Interpreting Figure~\ref{fig_line_width} is challenging given present knowledge. The hydrodynamical models of 
\citet{perinottoetal2004} and \citet{schonberneretal2005a, schonberneretal2005b} appear to be the most relevant, given 
their experiments with the AGB mass-loss rate, wind velocity, and metallicity. \emph{Only} \citet{schonberneretal2005b} 
consider the effect of metallicity on hydrodynamical models of planetary nebula evolution, and they find a greater 
acceleration of the nebular shell at lower metallicity because of the higher electron temperature achieved in the ionized 
shell. Both observation and the theory of dust-driven winds concur in that lower metallicity produces lower AGB wind 
velocities, though not necessarily lower mass-loss rates \citep[e.g.,][]{woodetal1992, marshalletal2004, mattssonetal2008, 
wachteretal2008, groenewegenetal2009, lagadecetal2010}. Also, the circumstellar shells of low-mass OH/IR stars have lower 
expansion velocities than those surrounding their higher mass counterparts (Lewis, Eder, \& Terzian 1990). Finally, though 
theoretical studies commonly find that the final white dwarf mass depends upon the metallicity of the progenitor star 
\citep[e.g.,][]{dominguezetal1999, weidemann2000}, to date, observation has been unable to substantiate this prediction 
\citep[e.g.,][]{catalanetal2008}. 

If we consider separately the star-forming or non-star-forming galaxies from Figure~\ref{fig_line_width}, each group approximates 
a metallicity sequence, though possibly with progenitor stellar populations of different ages. There is no obvious correlation of 
the line width with metallicity in either group. Since lower metallicity produces progenitor AGB stars with lower wind velocities, 
which translate into lower expansion velocities in the resulting planetary nebula \citep{perinottoetal2004}, other parameters being 
equal, the effect of metallicity must be  compensated. \citet{schonberneretal2005b} suggest that the higher electron temperatures 
at lower metallicities, with their consequently larger thermal pressures, provide greater acceleration of the nebular shell. Another 
possibility is that the progenitors of bright planetary nebulae with lower metallicity are slightly more massive, with their higher 
AGB wind velocities compensating for their lower metallicities. Greater acceleration is the simpler solution. Qualitatively, higher 
progenitor masses at lower metallicity allow the spectral differences noted in the past (Stasi\'nska, Richer, \& McCall 1998; Richer 
2006), but the variation cannot be too great, in order to comply with the small range needed to maintain the similar chemical 
abundance ratios and the variation of the PNLF peak luminosity with metallicity that are observed \citep{ciardulloetal2002, 
richermccall2008}.

There is no clear difference between the line widths of planetary nebulae in galaxies with and without star formation in 
Figure~\ref{fig_line_width}. Given the foregoing, the implication is that the stellar progenitors of bright planetary 
nebulae in all galaxies have similar masses, assuming that some mechanism exists to compensate for the lower velocities of 
the winds of AGB stars at lower metallicities. If so, at a given metallicity, bright planetary nebulae represent stars 
formed at similar epochs in galaxies with and without star formation. This may only be understood if the progenitor stars 
of bright planetary nebulae in all galaxies are of relatively low mass, since significant star formation stopped long ago 
(several Gyr) in many of the galaxies without star formation considered here.  Another option is that the denser ISM in 
star forming galaxies provides a greater impediment to the nebular outflow than does its counterpart in galaxies without 
star formation \citep[e.g.,][]{oeygarciasegura2004}. If so, progenitor stars of higher masses would be feasible in galaxies 
with ongoing star formation. Clearly, the issue must still be investigated in detail.

In galaxies with ongoing star formation, bright planetary nebulae usually have chemical abundances similar to those in the 
interstellar medium (ISM) in their host galaxies \citep{richermccall2007, magrinigoncalves2009, bresolinetal2010}. While 
this may be interpreted to suggest that the progenitors of their planetary nebulae are relatively young because the composition 
of the ISM has not evolved significantly since their formation, the ease with which the ISM composition can be changed decreases 
as the metallicity increases (and only the galaxies Leo A and Sextans A have very low metallicity). Thus, even in star-forming 
galaxies, the bright planetary nebulae need not arise from very recent star formation. Indeed, the chemical composition of bright 
planetary nebulae is very similar in galaxies with and without star formation \citep{richermccall2008}, again suggesting that 
their progenitor stars were of similar masses. 

The planetary nebulae that descend from massive progenitor stars need not be among the brightest planetary nebulae because of 
their rapid evolution (e.g., Villaver, Manchado, \& Garc\'ia-Segura 2002). On the other hand, they can produce the planetary 
nebulae with the largest outflow velocities for the ionized shell \citep[e.g.,][]{villaveretal2002, perinottoetal2004}. SMP83 
in the LMC, the high point in Figures~\ref{fig_dv_o3abun}--\ref{fig_dv_hblum} may be an example of a planetary nebula descended 
from a relatively massive progenitor that is also among the brightest.

Figure~\ref{fig_line_width} can therefore be understood if two conditions are met. First, some mechanism must exist that 
compensates the slower winds of low metallicity AGB stars. The greater thermal pressure resulting from ionization is the 
most natural explanation \citep{schonberneretal2005b}, though it is not the only possibility. Second, the masses of the 
progenitor stars of the brightest planetary nebulae in all galaxies should not differ too much, though some variation is 
feasible and even necessary to explain the differences in their low resolution spectra \citep{stasinskaetal1998, richer2006}. 

The trend of line width ($\Delta V_{0.5}$) within M31 agrees with these results (Figure~\ref{fig_M31_radial}). The chemical 
abundances in young stars and \ion{H}{2} regions indicate that the disc has a shallow oxygen abundance gradient (e.g., 
Dennefeld \& kunth 1981; Blair, Kirshner, \& Chevalier 1982; Venn et al. 2000; Trundle et al. 2002), with the oxygen abundance 
falling by less than a factor of 3 between nuclear distances of $0.5^{\circ}$ and $2^{\circ}$. Since Figure~\ref{fig_M31_radial} 
implies that the line width decreases only slightly as metallicity decreases, it is again necessary to invoke some mechanism 
to compensate for the drop in AGB wind velocity at lower metallicity.

In Figure~\ref{fig_dv_o3abun}, we plot the [\ion{O}{3}]$\lambda 5007$ line width as a function of the oxygen abundance. Clearly, 
the [\ion{O}{3}]$\lambda 5007$ line width does not vary strongly as a function of oxygen abundance. There may be greater dispersion 
among line widths for abundances below $12+\log(\mathrm O/\mathrm H)\sim 7.8$~dex. Likewise, there may be a deficit of narrow line 
widths above $12+\log(\mathrm O/\mathrm H)\sim 8.7$~dex. However, the statistics are poor in both cases.

In Figure~\ref{fig_dv_M5007}, we plot the line width as a function of the absolute [\ion{O}{3}]$\lambda 5007$ magnitude, $M_{5007}$. 
Again, there is no clear variation of the line width with $M_{5007}$, nor is there any obvious difference between systems with and 
without ongoing star formation. It is unfortunate that there are not more data for fainter planetary nebulae ($M_{5007} > -2$~mag), 
especially for systems without ongoing star formation, as it would be useful to determine whether the increased dispersion observed 
for fainter planetary nebulae in the Magellanic Clouds is a more general result (Figure~\ref{fig_dv_M5007}). 

When the line width is plotted as a function of the $I(5007)/I(\mathrm H\beta)$ ratio, there is a systematic difference in 
the distribution of line widths for the planetary nebulae from \emph{dwarf} galaxies with and without star formation. In 
Figure~\ref{fig_dv_o3hbrat}, there is an offset between the planetary nebulae in systems with and without ongoing star formation, 
with those from galaxies without star formation having larger $I(5007)/I(\mathrm H\beta)$ ratios at a given line width. Based 
upon the U-test \citep{walljenkins2003}, the difference between galaxies with and without star formation is significant at the 
90\% level when only bright planetary nebulae in \emph{dwarf galaxies} are included. Since this happens even though the dwarf 
galaxies with and without star formation have similar oxygen abundances (Figure~\ref{fig_dv_o3abun}), it is not an abundance 
effect, so it presumably arises as a result of differences in ionization structure or in the distribution of central star 
temperatures. The slight difference in progenitor masses proposed to explain Figure~\ref{fig_line_width} could conceivably 
produce this difference.

In Figure~\ref{fig_dv_o3hbrat}, the planetary nebulae in M31 extend to much higher $I(5007)/I(\mathrm H\beta)$ ratios than 
their counterparts in other galaxies. These are the most oxygen-rich planetary nebulae and simulations indicate that the 
$I(5007)/I(\mathrm H\beta)$ ratio varies as the square root of the oxygen abundance (Dopita, Jacoby, \& Vassiliadis 1992; 
M\'endez et al. 2005). However, the difference between the planetary nebulae in M31 and their counterparts in other galaxies 
is greater than this. The median value of the oxygen abundances for planetary nebulae in M31 differs from that for the 
planetary nebulae in the dwarf galaxies by less than a factor of two, but the difference in $I(5007)/I(\mathrm H\beta)$ 
ratios is greater than 50\%, which suggests that the change in ionization structure may accentuate at higher oxygen abundances.  

The most obvious trend that we find as a function of line width is with H$\beta$ luminosity (Figure~\ref{fig_dv_hblum}). The 
line widths define a broad swath in this diagram, but there are deficits of both large line widths at the highest H$\beta$ 
luminosities and narrow line widths at the lowest H$\beta$ luminosities. These deficits, especially that at high H$\beta$ 
luminosity, are not likely to be a selection effect, since young planetary nebulae rapidly achieve their maximum luminosity 
\citep{schonberneretal2007}, so they should be found on the right side of Figure \ref{fig_dv_hblum}. If there exist planetary 
nebulae that have very low H$\beta$ luminosities when young (with low [\ion{O}{3}]$\lambda 5007/\mathrm H\beta$), they could 
conceivably help fill in the deficit of low line widths at low H$\beta$ luminosity.

The existence of a trend of line width with H$\beta$ luminosity (Figure~\ref{fig_dv_hblum}), but not with $M_{5007}$ magnitude 
(Figure~\ref{fig_dv_M5007}), has important implications for the temporal evolution of bright planetary nebulae. Objects may be 
intrinsically bright in [\ion{O}{3}]$\lambda 5007$ if the $I(5007)/I(\mathrm H\beta)$ ratio is low or modest and the H$\beta$ 
luminosity is high, or if the $I(5007)/I(\mathrm H\beta)$ ratio is high and the H$\beta$ luminosity is at least modest. Thus, 
on average, [\ion{O}{3}]$\lambda 5007$-bright planetary nebulae fade monotonically in the light of H$\beta$. On the other hand, 
their evolution in [\ion{O}{3}]$\lambda 5007$ luminosity may be double-valued. In order to reproduce the tendency found between 
line width and H$\beta$ luminosity, the line width evolution should also be monotonic, on average, increasing as the H$\beta$ 
luminosity decreases. Recent hydrodynamical models concur with these three evolutionary trends, at least for stellar progenitors 
of lower masses \citep{villaveretal2002, perinottoetal2004, schonberneretal2005a, schonberneretal2007}.

Supposing that Figure~\ref{fig_dv_hblum} represents an evolutionary sequence, it offers insight into the positions of Fornax, 
NGC 147, and NGC 205 in Figure~\ref{fig_line_width}. For the planetary nebula in Fornax as well as PN04 in NGC 147 and PN01, 
PN07, and PN09 in NGC 205, low-resolution spectra find very weak \ion{He}{2}~$\lambda$4686, indicating that their central stars 
have not yet become very hot  \citep{goncalvesetal2007, kniazevetal2007, richermccall2008}. These two lines of evidence then 
imply that we observe these objects early in the planetary nebula phase and that, for Fornax and NGC 147, they bias their 
positions in Figure~\ref{fig_line_width} to unusually low values. 

Metallicity likely plays a role in the tendency to find a larger range of line widths ($\Delta V_{0.5}$) in the dwarf galaxies 
as compared to M31 and M33. The dwarf galaxies have lower metallicities and the peak luminosity of the PNLF is lower at lower 
metallicity \citep{ciardulloetal2002}. This might allow progenitor stars spanning a wider range of masses to contribute to the 
bright end of the PNLF at lower metallicity. Alternatively, planetary nebulae in a wider range of evolutionary states might 
contribute to the peak of the PNLF (Figure~\ref{fig_dv_hblum}). Either possibility would produce a wider range in line width 
at lower metallicity.

Hydrodynamical models have consistently predicted that the velocities of nebular shells should increase with time for planetary 
nebulae arising from progenitors of modest masses ($M \lesssim 2.5~M_{\odot}$; e.g., Schmidt-Voigt \& K\"oppen 1987; Kahn \& 
Breitschwerdt 1990; Mellema 1994; see also previous paragraph). \citet{dopitaetal1985, dopitaetal1988} first proposed such an evolutionary scheme for the 
kinematics of planetary nebulae in the Magellanic Clouds. \citet{richeretal2008, richeretal2010} have found similar evolution 
for the bright planetary nebulae in the Milky Way bulge. Figure~\ref{fig_dv_hblum} indicates that the acceleration of nebular 
shells is a general phenomenon, at least for the intrinsically brightest planetary nebulae (in the light of [\ion{O}{3}]$\lambda 5007$). 
Thus, there is now excellent qualitative agreement between theory and observation regarding the ionized shell's kinematic 
evolution for intrinsically bright planetary nebulae: with time, the shells are accelerated. The central star's important effect 
upon the nebular shell is clear. A more quantitative comparison must await the arrival of spatially-integrated line profiles 
from hydrodynamical models that may be directly compared with observations. 

For the PNLF to be a useful distance indicator, it must not be sensitive to the underlying stellar populations, a result found 
early in its use  \citep{ciardulloetal1989a}. \citet{merrettetal2006} confirm this, finding that the PNLF does not vary significantly 
with position in M31. Meanwhile, \citet{richermccall2008} find that the progenitors of bright planetary nebulae in all galaxies 
have undergone similar chemical enrichment processes. These results argue that the progenitor stellar populations of intrinsically 
bright planetary nebulae are similar in all galaxies, though they are clearly not identical \citep[e.g.,][]{stasinskaetal1998, 
ciardulloetal2002}. Likewise, the similar kinematics we find for the brightest planetary nebulae in all galaxies would appear to 
argue that there is not a large range in the masses of the stellar progenitors of these objects in different galaxies, whether 
star-forming or not. Their internal kinematics, therefore, add a third argument favoring progenitor stellar populations for the 
brightest planetary nebulae that are similar in all galaxies. 


\section{Conclusions}
\label{conclusions}

We present kinematic data for 211 bright extragalactic planetary nebulae in 11 Local Group galaxies. We present line profiles 
in the line of [\ion{O}{3}]$\lambda 5007$ for all objects and in the H$\alpha$ line for a small minority. At the signal-to-noise 
of our data, the line profiles are Gaussian, or nearly so, in all cases. The intrinsic line widths in [\ion{O}{3}]$\lambda 5007$ 
and H$\alpha$ are also similar. Thus, the line widths in [\ion{O}{3}]$\lambda 5007$ are an adequate description of the kinematics 
of most of the matter in the entire ionized shell in these objects.

We find that the average line widths for the bright planetary nebulae in all galaxies are similar (where we observed at least 
three objects). Given our current understanding, this result implies that the progenitors of bright planetary nebulae at lower 
metallicity are either slightly more massive or that the higher plasma temperatures at lower metallicities produce larger 
acceleration of the nebular shell. The approximate constancy of the line width also implies that there cannot be a large 
difference in the masses of the progenitors of bright planetary nebulae among galaxies, whether star-forming or not, though 
small variations are possible. Within M31, the line width decreases with increasing distance from the nucleus, in agreement 
with these deductions. 

As a general rule, the range of line widths is larger in dwarf galaxies than in M31 or M33. Presumably, this arises because, 
at lower metallicity, either a larger range of progenitor masses contribute bright planetary nebulae or bright planetary 
nebulae encompass a wider range of evolutionary states. On the other hand, there is no obvious correlation between the line 
width in [\ion{O}{3}]$\lambda 5007$ and either the oxygen abundance or the absolute [\ion{O}{3}]$\lambda 5007$ magnitude, $M_{5007}$. 

The most significant correlation is that between line width and the H$\beta$ luminosity. Since [\ion{O}{3}]$\lambda 5007$-bright 
planetary nebulae represent a monotonic fading sequence in the light of H$\beta$, this correlation implies that the ionized 
shells of bright planetary nebulae are accelerated during their early evolution, independently of the age or metallicity of 
the progenitor stellar population. Theory has long predicted this result, so our data are consistent with its general validity.

More generally, our measurements of the kinematics of bright planetary nebulae are in good accord with the results derived 
from photometry and low resolution spectroscopy. All three lines of reasoning require that intrinsically bright planetary 
nebulae descend from progenitor stellar populations spanning a relatively small range of masses. 

\acknowledgements

We thank the telescope operators during our runs, Gabriel Garc\'ia, Gustavo Melgoza, Salvador Monrroy, and Felipe Montalvo, 
for their help. We thank M. Arnaboldi for kindly providing the line widths for the planetary nebulae in the Virgo Cluster 
that are shown in Figure~\ref{fig_line_width}. We thank the referee for helpful comments and suggestions. We gratefully 
acknowledge financial support throughout this project from Conacyt grants 37214, 43121, 49447, and 82066 and from DGAPA-Universidad 
Nacional Aut\'onoma de M\'exico grants 108406-2, 108506-2, 112103, and 116908-3. We acknowledge the use of NASA's \emph{SkyView} 
facility (\url{http://skyview.gsfc.nasa.gov}) located at NASA Goddard Space Flight Center in generating Figure~\ref{fig_M31_pne}.

\vspace{0.3cm}

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