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We predict the stellar mass -- halo mass (SMHM) relationship for dwarf galaxies, using simulated galaxies with peak halo masses of M$_{rm peak} = 10^{11}$ M$_{odot}$ down into the ultra-faint dwarf range to M$_{rm peak} =$ 10$^7$ M$_{odot}$. Our simulated dwarfs have stellar masses of M$_{rm star} = $ 790 M$_{odot}$ to $8.2 times 10^8$ M$_{odot}$, with corresponding $V$-band magnitudes from $-2$ to $-18.5$. For M$_{rm peak} > 10^{10}$ M$_{odot}$, the simulated SMHM relationship agrees with literature determinations, including exhibiting a small scatter of 0.3 dex. However, the scatter in the SMHM relation increases for lower-mass halos. We first present results for well-resolved halos that contain a simulated stellar population, but recognize that whether a halo hosts a galaxy is inherently mass resolution dependent. We thus adopt a probabilistic model to populate dark halos below our resolution limit to predict an intrinsic slope and scatter for the SMHM relation. We fit linearly growing log-normal scatter in stellar mass, which grows to more than 1 dex at M$_{rm peak}$ $=$ 10$^8$ M$_{odot}$. At the faintest end of the SMHM relation probed by our simulations, a galaxy cannot be assigned a unique halo mass based solely on its luminosity. Instead, we provide a formula to stochastically populate low-mass halos following our results. Finally, we show that our growing log-normal scatter steepens the faint-end slope of the predicted stellar mass function.
High mass galaxies, with halo masses $M_{200} ge 10^{10} M_{odot}$, reveal a remarkable near-linear relation between their globular cluster (GC) system mass and their host galaxy halo mass. Extending this relation to the mass range of dwarf galaxies
We present results from the first combined study of variable stars and star formation history (SFH) of the Milky Way (MW) ultra-faint dwarf (UFD) galaxy Leo T, based on F606W and F814W multi-epoch archive observations obtained with the Wide Field Pla
We quantify the star formation (SF) in the inner cores ($mathcal{R}$/$R_{200}$$leq$0.3) of 24 massive galaxy clusters at 0.2$lesssim$$z$$lesssim$0.9 observed by the $Herschel$ Lensing Survey and the Cluster Lensing and Supernova survey with $Hubble$.
We present a multi-component structural analysis of the internal structure of $1074$ high redshift massive galaxies at $1<z<3$ from the CANDELS HST Survey. In particular we examine galaxies best-fit by two structural components, and thus likely formi
We investigate the evolution of galaxy masses and star formation rates in the Evolution and Assembly of Galaxies and their Environment (EAGLE) simulations. These comprise a suite of hydrodynamical simulations in a $Lambda$CDM cosmogony with subgrid m