相关论文: A new astrophysical solution to the Too Big To Fai…

Recent studies have established that extreme dwarf galaxies --whether satellites or field objects-- suffer from the so called "too big to fail" (TBTF) problem. Put simply, the TBTF problem consists of the fact that it is difficult to…

We use a semi-analytical model for the substructure of dark matter haloes to assess the too-big-to-fail (TBTF) problem. The model accurately reproduces the average subhalo mass and velocity functions, as well as their halo-to-halo variance,…

Recent studies found the densities of dark matter (DM) subhaloes which surround nearby dwarf spheroidal galaxies (dSphs) to be significantly lower than those of the most massive subhaloes expected around Milky Way sized galaxies in…

The Milky Way presents the too-big-to-fail (TBTF) problem that there are two observed satellite galaxies with maximum circular velocity larger than 55km/s, and others have velocity less than 25km/s, but the cold dark matter model predicts…

We use the Arecibo legacy fast ALFA (ALFALFA) 21cm survey to measure the number density of galaxies as a function of their rotational velocity, $V_\mathrm{rot,HI}$ (as inferred from the width of their 21cm emission line). Based on the…

Recent kinematical constraints on the internal densities of the Milky Way's dwarf satellites have revealed a discrepancy with the subhalo populations of simulated Galaxy-scale halos in the standard CDM model of hierarchical structure…

Simulating dwarf galaxy halos in a reionizing Universe puts severe constraints on the sub-grid model employed in the simulations. Using the same sub-grid model that works for simulations without a UV-background (UVB) results in gas poor…

Testing the standard cosmological model ($\Lambda$CDM) at small scales is challenging. Galaxies that inhabit low-mass dark matter halos provide an ideal test bed for dark matter models by linking observational properties of galaxies at…

We compare the half-light circular velocities, V_{1/2}, of dwarf galaxies in the Local Group to the predicted circular velocity curves of galaxies in the NIHAO suite of LCDM simulations. We use a subset of 34 simulations in which the…

Apparent deviations between properties of dwarf galaxies from observations and simulations are known to exist, such as the "Missing Dwarfs" problem, the too-big-to-fail problem, and the cusp-core problem, to name a few. Recent studies have…

We compare the dynamical masses of dwarf galaxies in the Local Group (LG) to the predicted masses of halos in the ELVIS suite of $\Lambda$CDM simulations, a sample of 48 Galaxy-size hosts, 24 of which are in paired configuration similar to…

We use a robust analytical model together with a high-resolution hydrodynamical cosmological simulation to demonstrate that in a $\Lambda$ cold dark matter ($\Lambda$CDM) universe, a small fraction of dwarf galaxies inhabiting dark matter…

The "too big to fail" problem is revisited by studying the tidal evolution of populations of dwarf satellites with different density profiles. The high resolution cosmological $\rm \Lambda CDM$ "ErisMod" set of simulations is used. These…

We examine the circular velocity profiles of galaxies in {\Lambda}CDM cosmological hydrodynamical simulations from the EAGLE and LOCAL GROUPS projects and compare them with a compilation of observed rotation curves of galaxies spanning a…

The scaling of disk galaxy rotation velocity with baryonic mass (the "Baryonic Tully-Fisher" relation, BTF) has long confounded galaxy formation models. It is steeper than the M ~ V^3 scaling relating halo virial masses and circular…

The observed central densities of Milky Way dwarf spheroidal galaxies (dSphs) are significantly lower than the densities of the largest (Vmax about 35 km/s) subhalos found in dissipationless simulations of Galaxy-size dark matter hosts. One…

The concordance cosmological model based on cold dark matter makes definitive predictions for the growth of galaxies in the Universe, which are being actively studied using numerical simulations. These predictions appear to contradict the…

We investigate the effect of self-interacting dark matter (SIDM) on the density profiles of $V_{\rm max} \simeq 40~km~s^{-1}$ isolated dwarf dark matter halos -- the scale of relevance for the too big to fail problem (TBTF) -- using very…

We use a series of N-body/smoothed particle hydrodynamics simulations and analytic arguments to show that the presence of an effective temperature floor in the interstellar medium at T_F ~ 10^4 K naturally explains the tendency for low-mass…

Despite recent success in forming realistic present-day galaxies, simulations still form the bulk of their stars earlier than observations indicate. We investigate the process of stellar mass assembly in low-mass field galaxies, a dwarf and…