diff options
Diffstat (limited to 'fg21sim')
| -rw-r--r-- | fg21sim/extragalactic/clusters/halo.py | 66 |
1 files changed, 40 insertions, 26 deletions
diff --git a/fg21sim/extragalactic/clusters/halo.py b/fg21sim/extragalactic/clusters/halo.py index baa1a36..273a611 100644 --- a/fg21sim/extragalactic/clusters/halo.py +++ b/fg21sim/extragalactic/clusters/halo.py @@ -59,6 +59,7 @@ import logging from functools import lru_cache import numpy as np +from scipy import integrate from . import helper from .solver import FokkerPlanckSolver @@ -215,7 +216,7 @@ class RadioHalo: """ t_merger = self._merger_time(t) cs = helper.speed_sound(self.kT(t_merger)) # [km/s] - v_turb = self._velocity_turb(t_merger) # [km/s] + v_turb = self._velocity_turb # [km/s] return v_turb / cs @property @@ -346,12 +347,9 @@ class RadioHalo: return tau_max t_merger = self._merger_time(t) - z_merger = COSMO.redshift(t_merger) - mass_merged = self.mass_merged(t_merger) - R_vir = helper.radius_virial(mass=mass_merged, z=z_merger) - L = self.f_lturb * R_vir # [kpc] + L = 2 * self.injection_radius # [kpc] cs = helper.speed_sound(self.kT(t_merger)) # [km/s] - v_turb = self._velocity_turb(t_merger) # [km/s] + v_turb = self._velocity_turb # [km/s] tau = (self.x_cr * cs**3 * L / (16*np.pi * self.zeta_ins * v_turb**4)) # [s kpc/km] tau *= AUC.s2Gyr * AUC.kpc2km # [Gyr] @@ -662,29 +660,43 @@ class RadioHalo: B = helper.magnetic_field(mass=mass, z=z, configs=self.configs) return B - def _velocity_turb(self, t): + @property + @lru_cache() + def _gas_density_profile_f(self): + """ + The gas density profile of the merged cluster. + + Returns + ------- + f(r) : function + A function that calculates the gas density of unit [Msun/kpc^3]. """ - Calculate the turbulence velocity dispersion (i.e., turbulence - Mach number). + return helper.calc_gas_density_profile( + mass=self.M_main+self.M_sub, z=self.z_merger) + + @property + @lru_cache + def _velocity_turb(self): + """ + Calculate the turbulence velocity dispersion (i.e., turbulence Mach + number). NOTE ---- During the merger, a fraction of the merger kinetic energy is - transferred into the turbulence within the assumed regions - (radius <= L, the injection scale). Then estimate the turbulence - velocity dispersion from its energy. + transferred into the turbulence within the region of radius R_turb. + Then estimate the turbulence velocity dispersion from its energy. Merger energy: - E_m ≅ 0.5 * f_gas * M_sub * v_vir^2 + E_merger ≅ 0.5 * f_gas * M_sub * v_vir^2 v_vir = sqrt(G*M_main / R_vir) Turbulence energy: - E_turb ≅ η_turb * E_m + E_turb ≅ η_turb * E_merger ≅ 0.5 * M_turb * <v_turb^2> - = 0.5 * f_gas * M_total(<L) * <v_turb^2> - = 0.5 * f_gas * f_mass(L/R_vir) * M_total * <v_turb^2> - M_total = M_main + M_sub => Velocity dispersion: - <v_turb^2> ≅ (η_turb/f_mass) * (M_sub/M_total) * v_vir^2 + <v_turb^2> ≅ v_vir^2 * η_turb*f_gas * (M_sub/M_turb) + where: + M_turb = int_0^R_turb ρ_gas(r)*4ᴨ*r^2 dr Returns ------- @@ -692,14 +704,16 @@ class RadioHalo: The turbulence velocity dispersion Unit: [km/s] """ - z = COSMO.redshift(t) - mass_merged = self.mass_merged(t) - mass_main = self.mass_main(t) - mass_sub = self.mass_sub(t) - R_vir = helper.radius_virial(mass_merged, z) * AUC.kpc2cm # [cm] - v2_vir = (AC.G * mass_main*AUC.Msun2g / R_vir) * AUC.cm2km**2 - fmass = helper.fmass_nfw(self.f_lturb) - v2_turb = v2_vir * (self.eta_turb / fmass) * (mass_sub / mass_merged) + rho_gas_f = self._gas_density_profile_f + R_turb = self.injection_radius # [kpc] + M_turb = 4*np.pi * integrate.quad(lambda r: rho_gas_f(r) * r**2, + a=0, b=R_turb)[0] # [Msun] + M_merged = self.M_main + self.M_sub + R_vir = helper.radius_virial(M_merged, self.z_merger) # [kpc] + R_vir *= AUC.kpc2cm # [cm] + v2_vir = (AC.G * self.M_main*AUC.Msun2g / R_vir) * AUC.cm2km**2 + v2_turb = (v2_vir * self.eta_turb * COSMO.baryon_fraction * + (self.M_sub / M_turb)) return np.sqrt(v2_turb) def _is_turb_active(self, t): |