Constraining the substructure of dark matter haloes with galaxy-galaxy lensing

TL;DR

This paper investigates how galaxy-galaxy lensing signals from SDSS and LSST-like surveys can constrain the mass and density profiles of dark matter subhaloes around satellite galaxies, revealing that LSST-like data significantly improve these constraints.

Contribution

The study demonstrates the potential of LSST-like surveys to precisely constrain dark matter subhalo properties using galaxy-galaxy lensing, compared to looser constraints from SDSS-like data.

Findings

SDSS-like surveys provide loose constraints on subhalo mass.

LSST-like surveys enable precise constraints on subhalo mass and density profiles.

Galaxy-galaxy lensing is effective for probing dark matter substructure.

Abstract

With galaxy groups constructed from the Sloan Digital Sky Survey (SDSS), we analyze the expected galaxy-galaxy lensing signals around satellite galaxies residing in different host haloes and located at different halo-centric distances. We use Markov Chain Monte Carlo (MCMC) method to explore the potential constraints on the mass and density profile of subhaloes associated with satellite galaxies from SDSS-like surveys and surveys similar to the Large Synoptic Survey Telescope (LSST). Our results show that for SDSS-like surveys, we can only set a loose constraint on the mean mass of subhaloes. With LSST-like surveys, however, both the mean mass and the density profile of subhaloes can be well constrained.