Showing papers by "Center for Theoretical Physics published in 2021"
•
TL;DR: In this article, the authors investigated how the dark matter halo mass of massive elliptical galaxies varies as a function of their properties, using weak gravitational lensing observations and a Bayesian hierarchical approach.
Abstract: Context. The assembly history of the stellar component of a massive
elliptical galaxy is closely related to that of its dark matter halo. Measuring
how the properties of galaxies correlate with their halo mass can help
understand their evolution. Aims. We investigate how the dark matter halo mass of elliptical galaxies
varies as a function of their properties, using weak gravitational lensing
observations. To minimise the chances of biases, we focus on galaxy properties
that can be determined robustly: the surface brightness profile and the colour. Methods. We selected 2439 central massive elliptical galaxies from the SDSS
spectroscopic sample. We first measured their surface brightness profile and
colours by fitting Sersic models to photometric data from the Kilo-Degree
Survey (KiDS). We fitted their halo mass distribution as a function of
redshift, rest-frame $r-$band luminosity, half-light radius and rest-frame
$u-g$ colour, using KiDS weak lensing data and a Bayesian hierarchical
approach. For the sake of robustness to assumptions on the large-radii
behaviour of the surface brightness, we repeated the analysis replacing total
luminosity and half-light radius with the luminosity within a 10~kpc aperture,
$L_{r,10}$, and the light-weighted surface brightness slope, $\Gamma_{10}$. Results. We did not detect any correlation between halo mass and either
half-light radius or colour, at fixed redshift and luminosity. Conclusions. Our results indicate that the average star formation efficiency
of massive elliptical galaxies has little dependence on their final size or
colour. This suggests that the origin of the diversity in the size and colour
distribution of these objects lies with properties other than halo mass.