Sign on

SAO/NASA ADS Astronomy Abstract Service

· Find Similar Abstracts (with default settings below)
· Electronic Refereed Journal Article (HTML)
· Full Refereed Journal Article (PDF/Postscript)
· arXiv e-print (arXiv:0811.2902)
· On-line Data
· References in the article
· Citations to the Article (6) (Citation History)
· Refereed Citations to the Article
· SIMBAD Objects (9)
· Associated Articles
· Also-Read Articles (Reads History)
·
· Translate This Page
Title:
Interstellar extinction and long-period variables in the Galactic centre
Authors:
Schultheis, M.; Sellgren, K.; Ramírez, S.; Stolovy, S.; Ganesh, S.; Glass, I. S.; Girardi, L.
Affiliation:
AA(Observatoire de Besançon, 41bis, avenue de l'Observatoire, 25000 Besançon, France ; Institut d'Astrophysique de Paris, CNRS, 98bis Bd Arago, 75014 Paris, France), AB(Astronomy Department, Ohio State University, Columbus, OH 43210, USA ), AC(IPAC, Caltech, Pasadena, CA 91125, USA ), AD(Spitzer Science Center, Caltech, Pasadena, CA 91125, USA ), AE(Physical Research Laboratory, Astronomy & Astrophysics Division, Ahmedabad, India ), AF(South African Astronomical Observatory, PO Box 9, Observatory 7935, South Africa), AG(Osservatorio di Padua, Italy)
Publication:
Astronomy and Astrophysics, Volume 495, Issue 1, 2009, pp.157-168 (A&A Homepage)
Publication Date:
02/2009
Origin:
EDP Sciences
Keywords:
ISM: dust, extinction, Galaxy: stellar content, stars: AGB and post-AGB
DOI:
10.1051/0004-6361:200810342
Bibliographic Code:
2009A&A...495..157S

Abstract

Aims: We derive a new map of the interstellar extinction near the Galactic Centre (GC), extending to much higher values of AV than previously available, and use the results obtained to better characterise the long-period variable star population of the region.
Methods: We take the Spitzer IRAC catalogue of GC point sources (Ramírez et al. 2008, ApJS, 175, 147) and combine it with new isochrones (Marigo et al. 2008, A&A, 482, 883) to derive extinctions based on the photometry of red giants and asymptotic giant branch (AGB) stars. We apply it to deredden the LPVs found by Glass et al. (2001) near the GC (Glass-LPVs). We make period-magnitude diagrams and compare them to those from other regions of different metallicity.
Results: Our new extinction map of the GC region covers 2.0° × 1.4° (280 × 200 pc at a distance of 8 kpc). The Glass-LPVs follow well-defined period-luminosity relations (PL) in the IRAC filter bands at 3.6, 4.5, 5.8, and 8.0 μm. The period-luminosity relations are similar to those in the Large Magellanic Cloud, suggesting that the PL relation in the IRAC bands is universal. We use ISOGAL data to derive mass-loss rates and find for the Glass-LPV sample some correlation between mass loss and pulsation period, as expected theoretically. Theoretical isochrones for a grid of different metallicities and ages are able to reproduce this relation. The GC has an excess of high-luminosity and long-period LPVs compared to the bulge, which supports previous suggestions that it contains a younger stellar population.

Figures 1 and 2 are only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/495/157

Associated Articles

Source Paper     Catalog Description    

Bibtex entry for this abstract   Preferred format for this abstract (see Preferences)
   

Find Similar Abstracts:

Use: Authors
Title
Keywords (in text query field)
Abstract Text
Return: Query Results Return    items starting with number
Query Form
Database: Astronomy
Physics
arXiv e-prints