Effects of environment on stellar metallicity profiles of late-type galaxies in the CALIFA survey

MURIEL, H.; COENDA, V.; MARTINEZ, H.J.; MAST, D.

ASTRONOMY AND ASTROPHYSICS

EDP SCIENCES S A

Lugar: Paris; Año: 2020 vol. 642 p. 132 - 140

0004-6361

Aims. We explore the effects of environment in the evolution of late-type galaxies by studying the radial profiles of light- and mass-weighted metallicities of galaxies in two discrete environments: field and groups.Methods. We used a sample of 167 late-type galaxies with stellar masses of 9 ≤ log(M _sun /M ) ≤ 12 drawn from the Calar Alto LegacyIntegral Field Area (CALIFA) survey. Firstly, we obtained light- and mass-weighted stellar metallicity profiles and stellar mass densityprofiles of these galaxies using publicly available data. We then classified them according to their environment into field and groupgalaxies. Finally, we studied the metallicity of galaxies in these two environments, including a comparison of the metallicity as afunction of radius, at a characteristic scale, and as a function of stellar mass surface density. As metallicity depends on galaxy mass,we took special care throughout the study to compare, in all cases, subsamples of galaxies in groups and in the field that have similarmasses.Results. We find significant differences between group and field late-type galaxies in terms of their metallicity: group galaxies aresystematically higher in metallicity than their field counterparts. We find that field galaxies, in general, have metallicity profiles thatshow a negative gradient in their inner regions and a shallower profile at larger radii. This is in contrast to the metallicity profiles ofgalaxies in groups, which tend to be flat in the inner regions and to have a negative gradient in the outer parts. Regarding the metallicityat the characteristic radius of the luminosity profiles, we consistently find that it is higher for group galaxies irrespective of galaxymass. At fixed local stellar surface mass density, group galaxies are again higher in metallicity, also the dependence of metallicity onsurface density is less important for group galaxies.Conclusions. The evidence of a clear difference in metallicity between group and field galaxies as a function of mass, spatial scale,and local stellar mass density is indicative of the different evolutionary paths followed by galaxies in groups and in the field. Wediscuss some possible implications of the observed differences.