{
  "id": "2309.15898",
  "version": "v1",
  "published": "2023-09-27T18:00:00.000Z",
  "updated": "2023-09-27T18:00:00.000Z",
  "title": "Three regimes of black hole feedback",
  "authors": [
    "Douglas Rennehan",
    "Arif Babul",
    "Belaid Moa",
    "Romeel Davé"
  ],
  "comment": "14 pages, 11 figures, comments more than welcome",
  "categories": [
    "astro-ph.GA",
    "astro-ph.IM"
  ],
  "abstract": "In theoretical models of galaxy evolution, black hole feedback is a necessary ingredient in order to explain the observed exponential decline in number density of massive galaxies. Most contemporary black hole feedback models in cosmological simulations rely on a constant radiative efficiency (usually $\\eta \\sim 0.1$) at all black hole accretion rates. We present a synthesis model for the spin-dependent radiative efficiencies of three physical accretion rate regimes, i.e. $\\eta = \\eta(j, \\dot{M}_\\mathrm{BH})$, for use in large-volume cosmological simulations. The three regimes include: an advection dominated accretion flow ($\\dot{M}_\\mathrm{BH} < 0.03\\,\\dot{M}_\\mathrm{Edd}$), a quasar-like mode ($0.03 < \\dot{M}_\\mathrm{BH} / \\dot{M}_\\mathrm{Edd} < 0.3$), and a slim disc mode ($\\dot{M}_\\mathrm{BH} > 0.3\\,\\dot{M}_\\mathrm{Edd}$). Additionally, we include a large-scale powerful jet at low accretion rates. The black hole feedback model we present is a kinetic model that prescribes mass loadings but could be used in thermal models directly using the radiative efficiency. We implemented our model into the \\texttt{Simba} galaxy evolution model to determine if it is possible to reproduce galaxy populations successfully, and provide a first calibration for further study. Using a $2\\times1024^3$ particle cosmological simulation in a $(150\\,\\mathrm{cMpc})^3$ volume, we found that the model is successful in reproducing the galaxy stellar mass function, black hole mass-stellar mass relationship, and stellar mass-halo mass relationship. Our model shines when we extrapolate to the galaxy group and cluster scale as it impressively predicts the observed baryon fraction within massive groups and low-mass clusters. Moving forward, this model opens new avenues for exploration of the impact of black hole feedback on galactic environments.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2023-09-27T18:00:00.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "accretion rate",
      "contemporary black hole feedback models",
      "radiative efficiency",
      "cosmological simulation",
      "black hole mass-stellar mass relationship"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 14,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}