Andrew R. Wetzel

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  • John K. Parejko, Tomomi Sunayama, +36 authors Zheng Zheng
  • 2013
We report on the small-scale (0.5 < r < 40 h−1 Mpc) clustering of 78 895 massive (M∗ ∼ 1011.3 M ) galaxies at 0.2 < z < 0.4 from the first two years of data from the Baryon Oscillation Spectroscopic Survey (BOSS), to be released as part of Sloan Digital Sky Survey (SDSS) Data Release 9 (DR9). We describe the sample selection, basic properties of the(More)
Galaxies are believed to be in one-to-one correspondence with simulated dark matter subhalos. We use high-resolution N-body simulations of cosmological volumes to calculate the statistical properties of subhalo (galaxy) major mergers at high redshift (z = 0.6− 5). We measure the evolution of the galaxy merger rate, finding that it is much shallower than the(More)
We analyze the clustering of red and blue galaxies from four samples spanning a redshift range of 0.4 < z < 2.0 to test the various scenarios by which galaxies evolve onto the red sequence. The data are taken from the UKIDSS Ultra Deep Survey, DEEP2, and COMBO-17. The use of clustering allows us to determine what fraction of the red sequence is made up of(More)
The clustering properties of dark matter halos are a firm prediction of modern theories of structure formation. We use two large volume, high-resolution N-body simulations to study how the correlation function of massive dark matter halos depends upon their mass, assembly history, and recent merger activity. We find that halos with the lowest concentrations(More)
Low-mass “dwarf” galaxies represent the most significant challenges to the cold dark matter (CDM) model of cosmological structure formation. Because these faint galaxies are (best) observed within the Local Group (LG) of the Milky Way (MW) and Andromeda (M31), understanding their formation in such an environment is critical. We present first results from(More)
In hierarchical structure formation, dark matter halos that merge with larger halos can persist as subhalos. These subhalos are likely hosts of visible galaxies. While the dense halo environment rapidly strips subhalos of their dark mass, the compact luminous material can remain intact for some time, making the correspondence of galaxies with severely(More)
High-resolution simulations of cosmological structure formation indicate that dark matter substructure in dense environments, such as groups and clusters, may survive for a long time. These dark matter subhalos are the likely hosts of galaxies.We examine the small-scale spatial clustering of subhalo major mergers at high redshift using high-resolution(More)
We study the structure, age and metallicity gradients, and dynamical evolution using a cosmological zoom-in simulation of a Milky Way-mass galaxy from the Feedback in Realistic Environments project. In the simulation, stars older than 6 Gyr were formed in a chaotic, bursty mode and have the largest vertical scaleheights (1.5–2.5 kpc) by z = 0, while stars(More)
In the Local Group (LG), almost all satellite dwarf galaxies that are within the virial radius of the Milky Way (MW) and Andromeda (M31) exhibit strong environmental influence. The orbital histories of these satellites provide the key to understanding the role of the MW/M31 halo, lower-mass groups, and cosmic reionization on the evolution of dwarf galaxies.(More)
Mergers are a common phenomenon in hierarchical structure formation, especially for massive galaxies and clusters, but their importance for dwarf galaxies in the Local Group remains poorly understood. We investigate the frequency of major mergers between dwarf galaxies in the Local Group using the ELVIS suite of cosmological zoom-in dissipationless(More)