Low-excitation blobs in the Magellanic Clouds

Meynadier, F. (1,2) and Heydari-Malayeri, M. (1)

(1) LERMA - Observatoire de Paris, France
(2) UPMC Université Paris 6, France

Aims : We study an unknown, or very poorly known, interstellar HII
component in the Magellanic Clouds. This is the first study ever
devoted to this class of objects, which we call Low-excitation blobs

Methods : We used low-dispersion spectroscopy carried out at ESO to
obtain emission line intensities of Ha, Hb, and [OIII] (4959+5007) for
15 objects in the Large Magellanic Cloud and 14 objects in the Small
Magellanic Cloud. Results are displayed in excitation ([oiii]/Hb
ratio) versus Hb luminosity diagrams.

Results : We show the presence of an LEB component in the Magellanic
Clouds and study its relationship with the already known class of
high-excitation blobs (HEBs). The newly found LEBs are lower
excitation counterparts of HEBs and are powered by less massive
exciting stars. Further study of LEBs is expected to provide new
pieces of information for a better understanding the low mass end of
the upper initial mass function in the Magellanic Clouds.

Reference: Accepted in A&A
Status: Manuscript has been accepted

Weblink: http://arxiv.org/abs/astro-ph/0610189


Email: Frederic.Meynadier@obspm.fr