tipy.py

Empirical model for the tidal evolution of subhalos as described in Errani & Navarro 2021. For a very brief introduction, see also this link.

Two ways to use this file:

• load it as a module: from tipy import *

  you then have access to the functions

  fecc_fit(rarp) eccentricity delay factor fecc = fecc_fit(rapo/rperi) (analytical, paper Eq. 4)

  VV0_track(rr0) tidal track Vmx/Vmx0 = VV0_track(rmx/rmx0) (analytical, paper Eq. 5)

  rr0_from_track(TT0) tidal track rmx/rmx0 = rr0_from_track(Tmx/Tmx0) (numerically solved)

  get_Tmx(Tmx0, t) time evolution of crossing time Tmx/Tperi = get_Tmx(Tmx0/Tperi, t/Torb) (analytical, paper Eq. 12 + 15 )

• run it as a program: python3 tipy.py

  this will run a worked out example for the evolution of an NFW subhalo

dNde.py

Empirical model to construct energy distribution of a tidally stripped stellar tracer as in E+22 Appendix G. For a very brief introduction, see also this link.

Also here, two ways to use this file:

• load it as a module: from dNde import *

  this gives access to the functions

  dNde(e,es,alpha,beta) Empirical energy distribution in the initial conditions (paper Eq. 13)

  f(e,emxt) Filter function, i.e., shape of the tidal energy truncation (paper Eq. 9)

  ef(ei,emxt) Energy mapping initial ei to final ef (paper Eq. 12)

  emxt_fit(MmxMmx0) Tidal truncation energy vs. remnant mass (paper Eq. 10)

  VV0_track(rr0) tidal track Vmx/Vmx0 = VV0_track(rmx/rmx0) (EN21 tital track)

  rr0_track_from_M(MmxMmx0) tidal track rmx/rmx0 = rr0_track_from_M(MmxMmx0) (numerically solved)

• run it as a program: python3 dNde.py

  this will run a worked out example for a stellar tracer embedded in an NFW halo that has been stripped to one per cent of its initial mass