Optical and near-infrared velocity dispersions of early-type galaxies
Abstract
We have carried out a systematic, homogeneous comparison of optical and near-infrared dispersions. Our magnitude-limited sample of early-type galax- ies (ETGs) in the Fornax cluster comprises 11 elliptical and 11 lenticular galaxies more luminous than MB = -17. We were able to determine the cen- tral dispersions based on the near-infrared CO absorption band head for 19 of those galaxies. The velocity dispersions range from less than 70 km s-1 to over 400 km s-1 . We compare our near-infrared velocity dispersions to the optical dispersions measured by Kuntschner (2000). Contrary to previ- ous studies, we find a one-to-one correspondence with a median fractional difference of 6.4 per cent. We examine the correlation between the relative dust mass and the fractional difference of the velocity dispersions, but find no significant trend.
- Publication:
-
Boletin de la Asociacion Argentina de Astronomia La Plata Argentina
- Pub Date:
- 2011
- Bibcode:
- 2011BAAA...54..341V