Modeling the color evolution of luminous red galaxies - improvements with empirical stellar spectra

By C. Maraston, Gustav Stromback, D. Thomas, D. Wake, R. Nichol. 2008

169 citations recorded by the source corpus.

Predicting the colors of Luminous Red Galaxies (LRGs) in the Sloan Digital Sky Survey (SDSS) has been a long-standing problem. The g,r,i colors of LRGs are inconsistent with stellar population models over the redshift range 0.1<z<0.7. The g-r colors in the models are on average redder than the data while the r-i colors in the models are bluer towards low redshift. Beyond redshift 0.4, the predicted r-i color becomes instead too red, while the predicted g-r agrees with the data. We provide a solution to this problem, through a combination of new astrophysics and a fundamental change to the stellar population modeling. We find that the use of the empirical library of Pickles (1998) instead of theoretical spectra modifies the predicted colors exactly in the way suggested by the data. The reason is a lower flux in the empirical libraries, with respect to the theoretical ones, in the wavelength range 5500-6500 AA. The discrepancy increases with decreasing effective temperature independently of gravity. This result has general implications for a variety of studies from globular clusters to high-redshift galaxies. The astrophysical part of our solution regards the composition of the stellar populations of these massive Luminous Red Galaxies. We find that on top of the previous effect one needs to consider a model in which ~3% of the stellar mass is in old metal-poor stars. Other solutions such as substantial blue Horizontal Branch at high metallicity or young stellar populations can be ruled out by the data. Our new model provides a better fit to the g-r and r-i colors of LRGs and gives new insight into the formation histories of these most massive galaxies. Our model will also improve the k- and evolutionary corrections for LRGs which are critical for fully exploiting present and future galaxy surveys.

Subfields: Astronomy and Astrophysics, Instrumentation

View Paper: https://www.semanticscholar.org/paper/c8d020abad57c3eacd82a92eaad3250b04f81530

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

In Instrumentation

Citations in the corpus

Analytical approximations of K-corrections in optical and near-infrared bands (2010, background): “They may originate from the fact that pegase.2 SSPs are built using the theoretical stellar library, shown to introduce colour differences between synthetic spectra and observed ones at least in the SDSS photometric system (Maraston et al. 2009).”
Stellar population models at high spectral resolution (2011, methodology): “…to improve on this situation, alternative versions of models have been constructed, where we have performed a concatenation with the SSP models of Maraston et al. (2009a), which are based on the fully theoretical UVBLUE/Kurucz library of high-resolution (R=10000) stellar spectra…”
Environment and self-regulation in galaxy formation (2009, background): “We expect this effect to be small, though, because the amount of metal-poor stars in luminous red galaxies in SDSS is of the order of only a few per cent by mass (Maraston et al. 2009).”
The clustering of galaxies in the sdss-iii baryon oscillation spectroscopic survey: Baryon acoustic oscillations in the data release 9 spectroscopic galaxy sample (2012, methodology): “The CMASS sample was designed to loosely follow a constant stellar mass cut (hence the name ConstantMASS) based on the passive galaxy template of Maraston et al. (2009), and was designed to produce a uniform mass distribution at all redshifts.”
Constraints on intrinsic alignment contamination of weak lensing surveys using the MegaZ-LRG sample (2010, methodology): “The Maraston et al. (2009) k+e-corrections display a slightly steeper increase with redshift, yieldingg− i corrections that are 0.03 lower at the redshift of the SDSS Main samples and about 0.1 higher at the mean redshift of the full MegaZ-LRG sample compared to the mean of the Wake et al. (2006)…”
THE CLUSTERING OF MASSIVE GALAXIES AT z ∼ 0.5 FROM THE FIRST SEMESTER OF BOSS DATA (2010, methodology): “As discussed in detail in Padmanabhan et al. (in preparation), the slope of thei − d⊥ cut is set to parallel the track of a passively evolving, constant stellar mass galaxy as determined from the population synthesis models of Maraston et al. (2009).”
MORPHOLOGICAL QUENCHING OF STAR FORMATION: MAKING EARLY-TYPE GALAXIES RED (2009, background): “Recent stellar population studies of red galaxies at high-redshift (Maraston et al. 2009; Tonini et al. 2009) indicate that their colors are consistent with some residual star-formation activity.”
Stellar masses of SDSS-III/BOSS galaxies at z ∼ 0.5 and constraints to galaxy formation models (2012, methodology): “A passively evolving model (Maraston et al. 2009) is adopted.”
SDSS-III Baryon Oscillation Spectroscopic Survey Data Release 12: galaxy target selection and large-scale structure catalogues (2015, background): “The Maraston et al. (2009) ‘LRG’ template is a model of a metal-rich population in passive evolution containing a small fraction of a metal-poor coeval population.”
Evolutionary stellar population synthesis with MILES – II. Scaled-solar and α-enhanced models (2015, background): “…tend to provide good fits to both, absorption line-strengths and spectra (e.g. Sánchez-Blázquez et al. 2006a; Yamada et al. 2006; Maraston & Strömbäck 2011; Vazdekis et al. 2012; Conroy 2013) and also photometric data (e.g. Maraston et al. 2009; Peacock et al. 2011; Ricciardelli et al. 2012).”
THE NINTH DATA RELEASE OF THE SLOAN DIGITAL SKY SURVEY: FIRST SPECTROSCOPIC DATA FROM THE SDSS-III BARYON OSCILLATION SPECTROSCOPIC SURVEY (2012, methodology): “Templates are based on Maraston (2005) and Maraston et al. (2009) for the star-forming and passive stellar population models, respectively.”
A CATALOG OF BULGE, DISK, AND TOTAL STELLAR MASS ESTIMATES FOR THE SLOAN DIGITAL SKY SURVEY (2013, background): “There is a well-documented discrepancy between the observed colors of red galaxies and the predicted colors of old, metal-rich populations in SPS models such that synthetic g−r photometry is ∼0.1 mag redder than is observed (e.g., Eisenstein et al. 2001; Maraston et al. 2009; Conroy et al. 2010).”
Re-evaluating old stellar populations (2018, background): “…] 2 2 M ay 2 01 Branch (AGB) dominates the integrated light, slight differences in model prescription can lead to substantially different predictions for a population SED, particularly in the near-infrared (e.g. Bruzual & Charlot 2003; Maraston 2005; Maraston et al. 2009; Dahmer-Hahn et al. 2018).”
A universal ultraviolet–optical colour–colour–magnitude relation of galaxies★ (2011, methodology): “This offset is probably of the same nature as that described by Maraston et al. (2009); however, no models based on empirical stellar spectra are available in the NUV yet.”
THE BARYON OSCILLATION SPECTROSCOPIC SURVEY OF SDSS-III (2012, background): “Target galaxies are chosen based on color and apparent magnitude cuts motivated by the stellar population models of Maraston et al. (2009).”