2015/06/30 by Aaron A. Dutton, Andrea V. Macciò, Gregory S. Stinson +3 · 2 citations
Physics and Astronomy · #Astronomy #Astronomy and Astrophysical Research #Astrophysics #Dark matter #Dark matter halo #Galactic halo #Galaxies: Formation, Evolution, Phenomena #Galaxy #Galaxy formation and evolution #Halo #Physics #Scientific Research and Discoveries #Star formation #astro-ph.CO #astro-ph.GA
paper · pdf · doi:10.1093/mnras/stv1755
21 pages, 18 figures, accepted to MNRAS
arxiv created 2015/07/31 · openalex publication_date 2015/08/31 · arxiv updated 2015/09/16 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We use cosmological hydrodynamical zoom-in simulations with the smoothed particle hydrodynamics code gasoline of four haloes of mass M200 ∼ 1013 M⊙ to study the response of the dark matter to elliptical galaxy formation. Our simulations include metallicity-dependent gas cooling, star formation and feedback from massive stars and supernovae, but not active galactic nuclei (AGN). At z = 2 the progenitor galaxies have stellar-to-halo mass ratios consistent with halo abundance matching, assuming a Salpeter initial mass function. However, by z = 0 the standard runs suffer from the well-known overcooling problem, overpredicting the stellar masses by a factor of ≳ 4. To mimic a suppressive halo quenching scenario, in our forced quenching (FQ) simulations, cooling and star formation are switched off at z = 2. The resulting z = 0 galaxies have stellar masses, sizes and circular velocities close to what is observed. Relative to the control simulations, the dark matter haloes in the FQ simulations have contracted, with central dark matter density slopes d log ρ/d log r ∼ −1.5, showing that dry merging alone is unable to fully reverse the contraction that occurs at z > 2. Simulations in the literature with AGN feedback, however, have found expansion or no net change in the dark matter halo. Thus, the response of the dark matter halo to galaxy formation may provide a new test to distinguish between ejective and suppressive quenching mechanisms.