Universidad Complutense de Madrid
E-Prints Complutense

The star formation history of CALIFA galaxies: Radial structures



Downloads per month over past year

Marino, Raffaella Anna and otros, ... (2014) The star formation history of CALIFA galaxies: Radial structures. Astronomy & Astrophysics, 562 . ISSN 0004-6361


Official URL: http://dx.doi.org/10.1051/0004-6361/201322011



We have studied the radial structure of the stellar mass surface density (μ∗) and stellar population age as a function of the total stellar mass and morphology for a sample of 107 galaxies from the CALIFA survey. We applied the fossil record method based on spectral synthesis techniques to recover the star formation history (SFH), resolved in space and time, in spheroidal and disk dominated galaxies with masses from 10^9 to 10^12 M_⊙. We derived the half-mass radius, and we found that galaxies are on average 15% more compact in mass than in light. The ratio of half-mass radius to half-light radius (HLR) shows a dual dependence with galaxy stellar mass; it decreases with increasing mass for disk galaxies, but is almost constant in spheroidal galaxies. In terms of integrated versus spatially resolved properties, we find that the galaxy-averaged stellar population age, stellar extinction, and μ_∗ are well represented by their values at 1 HLR. Negative radial gradients of the stellar population ages are present in most of the galaxies, supporting an inside-out formation. The larger inner (≤1 HLR) age gradients occur in the most massive (10^11 M_⊙) disk galaxies that have the most prominent bulges; shallower age gradients are obtained in spheroids of similar mass. Disk and spheroidal galaxies show negative μ∗ gradients that steepen with stellar mass. In spheroidal galaxies, μ∗ saturates at a critical value (~7 × 10^2 M_⊙/pc^2 at 1 HLR) that is independent of the galaxy mass. Thus, all the massive spheroidal galaxies have similar local μ_∗ at the same distance (in HLR units) from the nucleus. The SFH of the regions beyond 1 HLR are well correlated with their local μ_∗, and follow the same relation as the galaxy-averaged age and μ_∗; this suggests that local stellar mass surface density preserves the SFH of disks. The SFH of bulges are, however, more fundamentally related to the total stellar mass, since the radial structure of the stellar age changes with galaxy mass even though all the spheroid dominated galaxies have similar radial structure in μ_∗. Thus, galaxy mass is a more fundamental property in spheroidal systems, while the local stellar mass surface density is more important in disks.

Item Type:Article
Additional Information:

© ESO, 2014. Artículo firmado por 26 autores. CALIFA is the first legacy survey carried out at Calar Alto. The CALIFA collaboration would like to thank the IAA-CSIC and MPIA-MPG as major partners of the observatory, and CAHA itself, for the unique access to telescope time and support in manpower and infrastructures. We also thank the CAHA staff for the dedication to this project. Support from the Spanish Ministerio de Economía y Competitividad, through projects AYA2010-15081 (PI RGD), AYA2010-22111-C03-03 and AYA2010-10904E (SFS), AYA2010-21322-C03-02 (PSB), AYA2010-21322-C03-02 (JFB), AIB-2010-DE-00227 (JFB), the Ramón y Cajal Program (SFS, PSB and JFB), and FP7 Marie Curie Actions of the European Commission, via the Initial Training Network DAGAL under REA grant agreement number 289313 (JFB, GvdV) are warmly acknowledged. We also thank the Viabilidad, Diseño, Acceso y Mejora funding program, ICTS-2009-10, for funding the data acquisition of this project. RCF thanks the hospitality of the IAA and the support of CAPES and CNPq. ALA acknowledges support from INCT-A, Brazil. BH gratefully acknowledges the support by the DFG via grant Wi 1369/29-1. AG acknowledges funding from the FP7/2007-2013 under grant agreement n. 267251 (AstroFIt). R. A. Marino was also funded by the Spanish programme of International Campus of Excellence Moncloa (CEI). RGD acknowledges the support of CNPq (Brazil) through Programa Ciencia sem Fronteiras (401452/2012-3). We also thank the referee for her/his suggestions and comments.

Uncontrolled Keywords:Digital sky survey; Mass-metallicity relation; Stellar population gradients; Spatially-resolved spectroscopy; Color-magnitude relation; Disk-dominated galaxies; Band surface photometry; Line-strength maps; Field area survey; M-circle-dot
Subjects:Sciences > Physics > Astrophysics
Sciences > Physics > Astronomy
ID Code:37543
Deposited On:06 May 2016 12:57
Last Modified:10 Dec 2018 15:05

Origin of downloads

Repository Staff Only: item control page