RMxAA: Abstracts of Accepted Papers for Volume 55 Number 1


September 4, 2018

2018: September October November



September 2018


ENTRAINMENT FACTOR ON INDIVIDUAL GLITCH FRACTIONAL MOMENT OF INERTIA

I. O. Eya1,3, J. O. Urama2,3, and A. E. Chukwude1,2,3

1Department of Science Laboratory Technology, University of Nigeria, Nsukka, Nigeria.
2Department of Physics & Astronomy, University of Nigeria, Nsukka, Nigeria.
3Astronomy and Astrophysics Research Center, Faculty of Physical Sciences, University of Nigeria, Nsukka, Nigeria.


innocent.eya@unn.edu.ng

Received: May 21 2018
Accepted: September 4 2018

Abstract: The superfluid in the inner crust of neutron star is assumed to be the reservoir of momentum released in pulsar glitch. Recently, due to crustal entrainment, it is debatable whether the magnitude of the inner crust is sufficient to contain superfluid responsible for large glitches. This paper calculates the fractional moment of inertia (FMI)(i.e. the ratio of the inner crust superfluid moment of inertia to that of the coupled components) associated with individual glitches. It is shown that the effective moment of inertia associated with the transferred momentum is that of the entrained neutrons. The FMI for glitches in three pulsars, which exhibit the signature of exhausting their momentum reservoir were calculated and scaled with entrainment factor. Some of the glitches require inner crust superfluid with moment of inertia larger than the current suggested values of 7-10% of the stellar moment of inertia.




October 2018


SOLAR MID-INFRARED TELESCOPE

J. E. Mendoza-Torres1, J. S. Palacios-Fonseca2, M. Velázquez-de-la-Rosa1, P. Rodríguez-Montero1, A. De-Roa-Campoy3, E. Valadez-Campos3, M. O. Arias-Estrada1, J. Peña-Saint-Martín4, B. Rodríguez-Pedroza1, I. G&oacutE;mez-Arista3, M. Juárez-Gama5, K. Gottschalk6, and I. C. Medina-Carrillo2

1Instituto Nacional de Astrofísica, Óptica y Electrónica, Puebla, México.
2Universidad Autónoma de Nayarit, Nayarit, México.
3Facultad de Ciencias de la Electrónica, Benemérita Universidad Autónoma de Puebla, Puebla, México.
4Instituto de Astronomía, Universidad Nacional Autónoma de México, México.
5Facultad de Físico-Matemáticas, Benemérita Universidad Autónoma de Puebla, Puebla, México.
6Peace-Corps México, Querétaro, Querétaro, México.


mend@inaoep.mx

Received: January 19 2018
Accepted: October 9 2018

Abstract: We developed a mid infrared (MIR) solar telescope, centered at $10\mu$m. Various optical layouts were analyzed based on computer simulations and a Ritchey-Chretien 6-inches telescope was selected with a plate scale of $2.5\arcsec$/mm using a pyroelectric $4\times 16$~pixels detector. The angular resolution is $36\arcsec$/pixel with a field of view of $9.6^{\prime}\times 2.4^{\prime}$. Two germanium filters are used, one at the aperture of the telescope and other near its focal plane. With a laboratory black-body, the detector was characterized. The values given in counts follow a linear relation with the black-body temperature. The control systems for both, the telescope and the detector, were developed. For the filters, detector and electronics proper mechanical supports were designed. The system has been integrated and a user interface was developed. Preliminary observations have been made giving a Signal-to-Noise Ratio of $\sim 1000$.



EXACT SOLUTION FOR FLAT SCALE-INVARIANT COSMOLOGY

J. F. Jesus1,2

1Universidade Estadual Paulista (UNESP), Campus Experimental de Itapeva, Brazil.
2Universidade Estadual Paulista (UNESP), Faculdade de Engenharia, Guaratinguetá, Departamento de Física e Química, Brazil.


jfjesus@itapeva.unesp.br

Received: November 29 2017
Accepted: March 13 2018

Abstract: An exact solution for the spatially flat scale-invariant Cosmology, recently proposed by Maeder (2017a) is deduced. No deviation from the numerical solution was detected. The exact solution yields transparency for the dynamical equations and faster cosmological constraints may be performed.



EXTENSIVE PHOTOMETRY OF V1838 AQL DURING THE 2013 SUPEROUTBURST

J. Echevarría1, E. de Miguel2, J. V. Hernández Santisteban3, R. Michel4, R. Costero1, L. J. Sánchez1, A. Ruelas-Mayorga1, J. Olivares5, D. González-Buitrago6, J. L. Jones7, A. Oskanen8, W. Goff9, J. Ulowetz10, G. Bolt11, R. Sabo12, F.-J Hambsch13, D. Slauson14, and W. Stein15

1Instituto de Astronomía, Universidad Nacional Autónoma de México, México.
2Departamento de Ciencias Integradas, Universidad de Huelva, Huelva, Spain.
3Anton Pannekoek Institute for Astronomy, University of Amsterdam, Amsterdam, The Netherlands.
4Instituto de Astronomía, Universidad Nacional Autónoma de México, Ensenada, Baja California, México.
5Laboratoire d'astrophysique de Bordeaux, Univ. Bordeaux, Pessac, France.
6Departament of Physics and Astronomy, University of California, Irvine, CA, USA.
7CBA-Oregon, Jack Jones Observatory, Aurora, OR, USA.
8CBA-Finland, Hankasalmi Observatory, Muurame, Finland.
9CBA-California, Sutter Creek, CA, USA.
10CBA-Illinois, Northbrook Meadow Observatory, Northbrook, IL, USA.
11CBA-Australia, Craigie, Western Australia, Australia.
12CBA-Montana, Bozeman, MT, USA.
13CBA-Mol, Andromeda Observatory, Mol, Belgium.
14CBA-Iowa, Owl Ridge Observatory, IA, USA.
15CBA-Las Cruces, Las Cruces, NM, USA.


jer@astro.unam.mx

Received: August 8 2018
Accepted: October 24 2018

Abstract: We present an in-depth photometric study of the 2013 superoutburst of the recently discovered cataclysmic variable V1838 Aql and subsequent photometry near its quiescent state. A careful examination of the development of the superhumps is presented. Our best determination of the orbital period is $P_{\rm{orb}} = 0.05698(9)$~days, based on the periodicity of early superhumps. Comparing the superhump periods at stages A and B with the early superhump value we derive a period excess of $\epsilon = 0.024(2)$ and a mass ratio of $q = 0.10(1)$. We suggest that \pnv\ is approaching the orbital period minimum and thus has a low-mass star as a donor instead of a sub-stellar object.



ASYMMETRIC SHAPES OF RADIO RECOMBINATION LINES FROM IONIZED STELLAR WINDS

R. Ignace1,

1Department of Physics & Astronomy, East Tennessee State University, USA.


ignace@etsu.edu

Received: September 10 2018
Accepted: October 30 2018

Abstract: Recombination line profile shapes are derived for ionized spherical stellar winds at radio wavelengths. It is assumed that the wind is optically thick owing to free-free opacity. Emission lines of arbitrary optical depth are obtained assuming that the free-free photosphere forms in the outer, constant expansion portion of the wind. Previous works have derived analytic results for isothermal winds when the line and continuum source functions are equal. Here, semi-analytic results are derived for when the source functions are not equal to reveal that line shapes can be asymmetric about line center. A parameter study is presented and applications discussed.




November 2018


OPTIMAL TRAJECTORIES TO THE KUIPER BELT OBJECTS

D. M. Sanchez1, A. A. Sukhanov1,2, and A. F. B. A. Prado1

1National Institute for Space Research, INPE, Brazil.
2Space Research Institute of the Russian Academy of Sciences, IKI, Russia.


diogo.sanchez, antonio.prado@inpe.br

Received: June 22 2018
Accepted: November 12 2018

Abstract: The present paper searches for transfers from the Earth to three of the Kuiper Belt Objects (KBO): Haumea, Makemake, and Quaoar. These trajectories are obtained considering different possibilities of intermediate planet gravity assists. The model is based on the ``patched-conics'' approach. The best trajectories are found by searching for the minimum total $\Delta V$ transfer for a given launch window, inside the 2023-2034 interval, and disregarding the $\Delta V$ required for the capture at the target object. The results show transfers with duration below 20 years that spend a total $\Delta V$ under 10 km/s. There is also one trajectory for each of the KBOs with $\Delta V$ under 10 km/s and duration below 10 years, using the Jupiter swingby. For the 20-year trajectories, there are also asteroids in the main belt that could be encountered with low additional $\Delta V$, so increasing the scientific return of the mission.



MULTIWAVELENGTH OBSERVATIONS OF MASTER OT 075353.88+174907.6: A LIKELY SUPEROUTBURST OF A LONG PERIOD DWARF NOVA SYSTEM

A. S. Parikh1, J. V. Hernández Santisteban1, R. Wijnands1, and D. Page2

1Anton Pannekoek Institute for Astronomy, University of Amsterdam, The Netherlands.
2Instituto de Astronomía, Universidad Nacional Autónoma de México, México.


a.s.parikh@uva.nl

Received: September 18 2018
Accepted: November 14 2018

Abstract: MASTER OT 075353.88+174907.6 was a blue optical transient reported by the MASTER-Net project on 2017 Oct 31. We carried out multiwavelength follow-up observations of this source during its 2017 outburst using {\it Swift} and RATIR. The source was found to be $\gtrsim$4.4 mag above its quiescent level during the peak of the outburst and the outburst lasted $\gtrsim$19 days. Our observations suggest that it was a superoutburst of a long orbital period U Geminorum type dwarf nova system. The spectral energy distribution during the initial slow decay phase of the outburst was consistent with a disk-dominated spectra (having spectral indices $\Gamma \! \sim$1.5--2.3). After this phase, the UV flux decreased slower than the optical and the spectral energy distribution was very steep with indices $\Gamma \! \sim$3.7$\pm$0.7. This slow decay in the UV may be the emission from a cooling white dwarf heated during the outburst. No X-ray emission was detected from the source since it is likely located at a large distance $>$2.3 kpc.