Astronomy and Astrophysics – Astrophysics
Scientific paper
2008-03-20
Astronomy and Astrophysics
Astrophysics
26 pages, 9 figures and 9 tables. PDF file; accepted for publication in MNRAS
Scientific paper
10.1111/j.1365-2966.2008.13235.x
Stellar population characteristics are presented for a sample of low luminosity early-type galaxies (LLEs) in order to compare them with their more luminous counterparts. Long-slit spectra of a sample of 10 LLEs were taken with the ESO New Technology Telescope, selected for their low luminosities. Line strengths were measured on the Lick standard system. Lick indices for these LLEs were correlated with velocity dispersion (sigma), alongside published data for a variety of Hubble types. The LLEs were found to fall below an extrapolation of the correlation for luminous ellipticals and were consistent with the locations of spiral bulges in plots of line strengths versus sigma. Luminosity weighted average ages, metallicities and abundance ratios were estimated from chi-squared fitting of 19 Lick indices to predictions from simple stellar population models. The LLEs appear younger than luminous ellipticals and of comparable ages to spiral bulges. These LLEs show a bimodal metallicity distribution, consisting of a low metallicity group (possibly misclassified dwarf spheroidal galaxies) and a high metallicity group (similar to spiral bulges). Finally, they have low alpha-element to iron-peak abundance ratios indicative of slow, extended star formation.
Northeast M. S.
Sansom Ann E.
No associations
LandOfFree
Bimodality in low luminosity E and S0 galaxies does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Bimodality in low luminosity E and S0 galaxies, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Bimodality in low luminosity E and S0 galaxies will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-578253