Related papers: Ultra-Diffuse, Ultra-Different: Observed vs. Simul…
We investigate the evolution of the galaxy stellar mass function at high-redshift ($z\ge 5$) using a pair of large cosmological hydrodynamical simulations: {\em MassiveBlack} and {\em MassiveBlack-II}. By combining these simulations we can…
McKay et al. (2002) have recently used measurements of weak galaxy-galaxy lensing in the Sloan Digital Sky Survey to estimate the cross correlation between galaxies and the projected dark matter density field. They derive a relation between…
We use 25 simulated galaxies from the NIHAO project to define and characterize a variety of kinematic stellar structures: thin and thick discs, large scale single discs, classical and pseudo bulges, spheroids, inner discs, and stellar…
Cosmic voids, the underdense regions in the universe, are particularly sensitive to diffuse density components such as cosmic neutrinos. This sensitivity is enhanced by the match between void sizes and the free-streaming scale of massive…
Many ultra diffuse galaxies (UDGs) have now been identified in clusters of galaxies. However, the number of nearby UDGs suitable for detailed follow-up remain rare. Our aim is to begin to identify UDGs in the environments of nearby bright…
Dark matter haloes and subhaloes that host no luminous counterpart are predicted within our current understanding of galaxy formation within a $\Lambda$CDM paradigm. Observational tests, such as gravitational lensing, have made potential…
Strong gravitational lensing observations can test structure formation models by constraining the masses and concentrations of subhaloes in massive galaxy clusters. Recent work has concluded that cluster subhaloes are more abundant and/or…
The discovery of the ultra-diffuse galaxy NGC 1052-DF2 and its peculiar population of star clusters has raised new questions about the connections between galaxies and dark matter halos at the extremes of galaxy formation. In light of…
Observed kinematical data of 40 Local Group (LG) members are used to derive the dark matter halo mass of such galaxies. Haloes are selected from the theoretically expected LG mass function and two different density profiles are assumed, a…
Young tidal dwarf galaxies (TDGs) are observed in the tidal debris of gas-rich interacting galaxies. In contrast to what is generally assumed to be the case for isolated dwarf galaxies, TDGs are not embedded in their own dark matter (DM)…
The connection between dark matter halos and galactic baryons is often not well-constrained nor well-resolved in cosmological hydrodynamical simulations. Thus, Halo Occupation Distribution (HOD) models that assign galaxies to halos based on…
Ultra-compact dwarf galaxies (UCDs) are stellar systems with masses of around 10^7 to 10^8 Msun and half mass radii of 10-100 pc. They have some properties in common with massive globular clusters, however dynamical mass estimates have…
We simulate deep images from the Hubble Space Telescope (HST) using semi-empirical models of galaxy formation with only a few basic assumptions and parameters. We project our simulations all the way to the observational domain, adding…
We present new redshift measurements for 19 candidate, ultra-diffuse galaxies (UDGs) from the Systematically Measuring Ultra-Diffuse Galaxies (SMUDGes) survey after conducting a long-slit, spectroscopic follow-up campaign on 23 candidates…
Dwarf galaxies serve as powerful laboratories for investigating the underlying physics of galaxy evolution including the impact of baryonic feedback processes and environmental influences. We compare the visual and structural properties of…
We present a comparison of the observed evolving galaxy stellar mass functions with the predictions of eight semi-analytic models and one halo occupation distribution model. While most models are able to fit the data at low redshift, some…
We measure the mass function of dark matter halos in a large set of collisionless cosmological simulations of flat LCDM cosmology and investigate its evolution at z<~2. Halos are identified as isolated density peaks, and their masses are…
We suggest a possible mechanism of ultra diffuse galaxy formation: the UDGs may occur as a result of a central collision of galaxies. If the galaxies are young and contain a lot of gas, the collision may kick all the gas off the systems and…
The condensation of gas and stars in the inner regions of dark matter halos leads to a more concentrated dark matter distribution. While this effect is based on simple gravitational physics, the question of its validity in hierarchical…
We present a simple formalism to interpret two galaxy statistics, the UV luminosity function and two-point correlation functions for star-forming galaxies at z~4, 5, 6 in the context of LCDM cosmology. Both statistics are the result of how…