2026-06-27T12:36:21Zhttps://docta.ucm.es/rest/oai/request

oai:docta.ucm.es:20.500.14352/444562024-09-03T14:47:04Zcom_20.500.14352_14col_20.500.14352_15

Matkovic, A. Guzmán, R. Sánchez Blázquez, Patricia Gorgas García, Francisco Javier Cardiel López, Nicolás Gruel, N. 2023-06-20T03:47:44Z 2023-06-20T03:47:44Z 2009-02-01 0004-637X 10.1088/0004-637X/691/2/1862 https://hdl.handle.net/20.500.14352/44456 http://dx.doi.org/10.1088/0004-637X/691/2/1862 http://iopscience.iop.org/ We present line-strength measurements for 74 early-type galaxies in the core of the Coma cluster reaching down to velocity dispersions, sigma, of 30 km s(-1). The index-sigma relations for our sample, including galaxies with sigma < 100 km s(-1) (low-sigma), differ in shape depending on which index is used. We note two types of relations for the metallic indices: one showing a break in the slope around similar to 100 km s(-1) and another group with strong linear relations between an index and log s. We find no connection between the behavior of index-sigma relations with either alpha- or Fe-peak elements. However, we find indications that the relations are tighter for indices which do not depend on the microturbulent velocities of stellar atmospheres. We confirm previous results that low-sigma galaxies including dE/dS0s are on average younger, less metal rich, and have lower [alpha/Fe] in comparison with E/S0s. Our data show that these trends derived for high-sigma galaxies extend down to dE/dS0s. This is a factor of similar to 2 lower in sigma than previously published work. We confirm that the observed anticorrelation between age and metallicity for high-sigma galaxies is consistent with the effects of correlated errors. Low-sigma galaxies also show a similar relation between age and metallicity as a result of correlated errors. However, they are offset from this relationship so that, on average, they are less metal rich and younger than their high-sigma counterparts. eng open access Kinematic properties and stellar populations of faint early-type galaxies. II. Line-strength measurements of central coma galaxies journal article