2004/07/12 by H. Kuntschner, Harald Kuntschner · 47 citations
Mathematics · Physics and Astronomy · #Astronomy #Astronomy and Astrophysical Research #Astrophysics #Balmer series #Emission spectrum #Galaxies: Formation, Evolution, Phenomena #Galaxy #Line (geometry) #Luminosity #Mathematics #Physics #Population #Spectral line #Star formation #Stellar population #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1051/0004-6361:20041414
published in Astronomy and Astrophysics 426(2), 737-745 (EDP Sciences) · 10 pages, 8 figures, accepted by A&A
arxiv created 2004/07/12 · openalex publication_date 2004/10/11 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We investigate line-of-sight velocity distribution (LOSVD) corrections for absorption line-strength indices of early-type galaxies in the Lick/IDS system. This system is often used to estimate basic stellar population parameters such as luminosity weighted ages and metallicities. Using single stellar population model spectral energy distributions by Vazdekis (1999) we find that the LOSVD corrections are largely insensitive to changes in the stellar populations for old galaxies (age Gyr). Only the Lick/IDS Balmer series indices show an appreciable effect, which is on the order of the correction itself. Furthermore, we investigate the sensitivity of the LOSVD corrections to non-Gaussian LOSVDs. In this case the LOSVD can be described by a Gauss-Hermite series and it is shown that typical values of h3 and h4 observed in early-type galaxies can lead to significant modifications of the LOSVD corrections and thus to changes in the derived luminosity weighted ages and metallicities. A new, simple parameterisation for the LOSVD corrections, taking into account the h3 and h4 terms, is proposed and calibrations given for a subset of the Lick/IDS indices and two additional indices applicable to old (>3 Gyr) stellar populations.