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Adaptive AGN heating temperature jump

Yannick Bahé requested to merge xy-varagn into master

This merge request implements a model to adaptively calculate the AGN heating temperature jump dT, rather than using a prescribed constant value.

dT is calculated as min(max(dT_min, dT_mass, dT_crit, dT_local), dT_max), where:

  • dT_min and dT_max are (constant) min/max values for dT (default: 1e7 K, 3e9 K)
  • dT_mass = theta * (m_BH / m_ref)^beta (with theta, m_ref, and beta as free parameters, and m_BH the subgrid mass of the BH). This is intended as a proxy for a scaling with virial halo temperature, assuming that m_BH is proportional to M_halo. Beta is then fixed at 2/3. The default values for theta and m_ref are 3e8 K and 1e8 M_sun, respectively; tests in 25 Mpc boxes show little impact of the exact values.
  • dT_crit is the critical temperature required to avoid numerical cooling losses according to Dalla Vecchia & Schaye (2012), multiplied by an arbitrary factor (default: 1).
  • dT_local is the (SPH-smoothed) average gas temperature in the kernel, multiplied with an arbitrary factor (default: 0, i.e. do not take local temperature into account).

So far, only the EAGLE_ICs/EAGLE_25 parameter example is updated with the new parameters.

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