Abstract:
Dwarf galaxies serve as powerful probes of both the nature of dark matter and the effects of baryonic processes. Over the past two decades, observations of nearby dwarf galaxies have revealed tensions with predictions from simulations based on the standard ΛCDM cosmology. In this talk, I will present the Merian Survey, a medium-band imaging survey conducted with the Dark Energy Camera (DECam), which is designed to build a large statistical sample of dwarf galaxies to detect their weak gravitational lensing signals. I will show the weak lensing measurements of dwarf galaxies using data from Merian DR1, as well as the gas properties of the dwarf halos. Finally, I will discuss the future of understanding of the galaxy–halo connection at low-masses using upcoming imaging and spectroscopic surveys. These include the newly granted IBIS survey (353 nights on DECam), the proposed medium-band HSC-NIJI survey, and future spectroscopic surveys such as DESI-2 and Spec-S5.
