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Full-Text Articles in Physical Sciences and Mathematics
Baryon Dynamics, Dark Matter Substructure, And Galaxies, Dh Weinberg, S Colombi, R Dave, N Katz
Baryon Dynamics, Dark Matter Substructure, And Galaxies, Dh Weinberg, S Colombi, R Dave, N Katz
Astronomy Department Faculty Publication Series
By comparing a collisionless cosmological N-body simulation (DM) to a smoothed particle hydrodynamics simulation (SPH) with the same initial conditions, we investigate the correspondence between dark matter subhalos produced by collisionless dynamics and galaxies produced by dissipative gas dynamics in a dark matter background. When galaxies in the SPH simulation fall into larger groups and become satellites, they retain local dark matter concentrations (SPH subhalos) whose mass is typically 5 times the galaxy baryonic mass (compared to the simulation's universal ratio Ωdm/Ωb 7.5). The more massive subhalos of the SPH simulation generally have corresponding subhalos of …
Spectroscopic Confirmation Of An Extreme Starburst At Redshift 4.547, P Capak, Cl Carilli, N Lee, T Aldcroft, H Aussel, E Schinnerer, Gw Wilson, Min Yun, A Blain, M Giavalisco, O Ilbert, J Kartaltepe, Ks Lee, H Mccracken, B Mobasher, M Salvato, S Sasaki, Ks Scott, K Sheth, Y Shioya, D Thompson, M Elvis, Db Sanders, Nz Scoville, Y Tanaguchi
Spectroscopic Confirmation Of An Extreme Starburst At Redshift 4.547, P Capak, Cl Carilli, N Lee, T Aldcroft, H Aussel, E Schinnerer, Gw Wilson, Min Yun, A Blain, M Giavalisco, O Ilbert, J Kartaltepe, Ks Lee, H Mccracken, B Mobasher, M Salvato, S Sasaki, Ks Scott, K Sheth, Y Shioya, D Thompson, M Elvis, Db Sanders, Nz Scoville, Y Tanaguchi
Astronomy Department Faculty Publication Series
We report the spectroscopic confirmation of a submillimeter galaxy (SMG) at z = 4.547 with an estimated LIR = (0.5-2.0) × 1013 L. The spectra, mid-IR, and X-ray properties indicate the bolometric luminosity is dominated by star formation at a rate of >1000 M yr−1. Multiple, spatially separated components are visible in the Lyα line with an observed velocity difference of up to 380 km s−1 and the object morphology indicates a merger. The best-fit spectral energy distribution and spectral line indicators suggest the object is 2-8 Myr old and contains >1010 M …
Ongoing Assembly Of Massive Galaxies By Major Merging In Large Groups And Clusters From The Sdss, Dh Mcintosh, Yc Guo, J Hertzberg, N Katz, Hj Mo, Fc Van Den Bosch, Xh Yang
Ongoing Assembly Of Massive Galaxies By Major Merging In Large Groups And Clusters From The Sdss, Dh Mcintosh, Yc Guo, J Hertzberg, N Katz, Hj Mo, Fc Van Den Bosch, Xh Yang
Astronomy Department Faculty Publication Series
We investigate the incidence of major mergers creating massive (Mstar > 1011 M⊙) galaxies in present-day (z≤ 0.12) groups and clusters. Using a volume-limited sample of 845 groups with dark matter halo masses above 2.5 × 1013 M⊙, we isolate 221 galaxy pairs with ≤1.5 r-band magnitude differences, ≤30 kpc projected separations and combined masses above 1011 M⊙. We fit the r-band images of each pair as the line-of-sight projection of symmetric models and identify 38 mergers by the presence of residual asymmetric structure associated with …