The ATLAS3D Project – XXX. Star formation histories and stellar population scaling relations of early-type galaxies

By R. McDermid, K. Alatalo, L. Blitz, Frédéric Bournaud, M. Bureau, M. Cappellari, A. Crocker, Roger Davies, T. Davis, P. de Zeeuw and 13 more. 2015

306 citations recorded by the source corpus.

We present the stellar population content of early-type galaxies from the ATLAS^(3D) survey. Using spectra integrated within apertures covering up to one effective radius, we apply two methods: one based on measuring line-strength indices and applying single stellar population (SSP) models to derive SSP-equivalent values of stellar age, metallicity, and alpha enhancement; and one based on spectral fitting to derive non-parametric star formation histories, mass-weighted average values of age, metallicity, and half-mass formation time-scales. Using homogeneously derived effective radii and dynamically determined galaxy masses, we present the distribution of stellar population parameters on the Mass Plane (M_(JAM), σ_e, R^(maj)_e), showing that at fixed mass, compact early-type galaxies are on average older, more metal-rich, and more alpha-enhanced than their larger counterparts. From non-parametric star formation histories, we find that the duration of star formation is systematically more extended in lower mass objects. Assuming that our sample represents most of the stellar content of today's local Universe, approximately 50 per cent of all stars formed within the first 2 Gyr following the big bang. Most of these stars reside today in the most massive galaxies (>10^(10.5) M⊙), which themselves formed 90 per cent of their stars by z ∼ 2. The lower mass objects, in contrast, have formed barely half their stars in this time interval. Stellar population properties are independent of environment over two orders of magnitude in local density, varying only with galaxy mass. In the highest density regions of our volume (dominated by the Virgo cluster), galaxies are older, alpha-enhanced, and have shorter star formation histories with respect to lower density regions.

Subfields: Astronomy and Astrophysics, Instrumentation

View Paper: https://www.semanticscholar.org/paper/ce653a2abf29a93b8b1f34e5620672e0c7563def

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Astronomy and Astrophysics

1. C. Conroy
2. M. Cappellari
3. P. V. van Dokkum
4. P. Hopkins
5. L. Hernquist
6. R. Dav'e
7. A. Cimatti
8. K. Bundy

In Instrumentation

1. C. Conroy
2. M. Cappellari
3. P. V. van Dokkum
4. P. Hopkins
5. L. Hernquist
6. A. Cimatti
7. R. Dav'e
8. K. Bundy

Citations in the corpus

• Structure and Kinematics of Early-Type Galaxies from Integral Field Spectroscopy (2016, methodology): “This is because systematic changes in the galaxy population were already known, with galaxies becoming older and more metal rich with increasing mass or σ (e.g. Thomas et al. 2005; McDermid et al. 2015).”
• Setting the Stage for Cosmic Chronometers. II. Impact of Stellar Population Synthesis Models Systematics and Full Covariance Matrix (2020, background): “…solar to slightly oversolar metallicities (Gallazzi et al. 2005; Onodera et al. 2012; Gallazzi et al. 2014; Conroy et al. 2014; Onodera et al. 2015; McDermid et al. 2015; Citro et al. 2016; Comparat et al. 2017; Estrada-Carpenter et al. 2019; Kriek et al. 2019; Morishita et al. 2019; Saracco et…”
• SDSS IV MaNGA – spatially resolved diagnostic diagrams: a proof that many galaxies are LIERs (2016, background): “…of full spectral fitting (Heavens et al. 2000; Panter et al. 2004; Fernandes et al. 2005; Gallazzi et al. 2006; Sánchez-Blázquez et al. 2011; Wilkinson et al. 2015; McDermid et al. 2015) to derive age and metallicity of the stellar population, thus largely mitigating the age-metallicity degeneracy.”
• Modelling and interpreting spectral energy distributions of galaxies with BEAGLE (2016, background): “MNRAS 462, 1415–1443 (2016) by guest on O ctober 5, 2016 http://m nras.oxfordjournals.org/ D ow nloaded from constraints (e.g. Tojeiro et al. 2013; McDermid et al. 2015; Citro et al. 2016; López Fernández et al. 2016).”
• Deriving Physical Properties from Broadband Photometry with Prospector: Description of the Model and a Demonstration of its Accuracy Using 129 Galaxies in the Local Universe (2016, methodology): “We compare photometric stellar metallicities to spectroscopic metallicities from the ATLAS-3D survey (Cappellari et al. 2011), presented in McDermid et al. (2015).”
• Improving the full spectrum fitting method: accurate convolution with Gauss-Hermite functions (2016, methodology): “…for ‘full spectrum’ fitting to study the galaxies stellar population (e.g. Onodera et al. 2012; Cappellari et al. 2012; Morelli et al. 2013, 2015; McDermid et al. 2015; Shetty & Cappellari 2015), but it can also be used when extracting the stellar kinematics with ppxf (e.g. Emsellem et al.…”