Mid infrared colors of early type galaxies

Citation
A. Bressan et al., Mid infrared colors of early type galaxies, ASTRO SP SC, 277, 2001, pp. 251-254
Citations number
9
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Space Sciences
Journal title
ASTROPHYSICS AND SPACE SCIENCE
ISSN journal
0004-640X → ACNP
Volume
277
Year of publication
2001
Supplement
1
Pages
251 - 254
Database
ISI
SICI code
0004-640X(2001)277:<251:MICOET>2.0.ZU;2-B
Abstract
We compare the mid infrared colors of early type galaxies with isochrones t hat suitably account for the effects of dust in the circumstellar envelopes of AGB stars. We show that these stars affect significantly the integrated colors in the ISO bands. The excess at 10 mum observed in some early type galaxies combined with the optical spectrum, is compatible with a 100% old metal rich population. Limits on the additional young components are: age 0 .2 Gyr, mass=0.5% and E(B-V)greater than or equal to0.5 or age 3 Gyr, mass 10% and E(B-V)greater than or equal to0.2.