diff options
| -rw-r--r-- | fg21sim/extragalactic/clusters/helper.py | 33 |
1 files changed, 29 insertions, 4 deletions
diff --git a/fg21sim/extragalactic/clusters/helper.py b/fg21sim/extragalactic/clusters/helper.py index 737d05b..d761915 100644 --- a/fg21sim/extragalactic/clusters/helper.py +++ b/fg21sim/extragalactic/clusters/helper.py @@ -112,6 +112,33 @@ def calc_gas_density_profile(mass, z, f_rc=0.1, beta=0.8): return beta_model(rho0, rc, beta) +def radius_overdensity(mass, overdensity, z=0.0): + """ + Calculate the radius within which the mean density is ``overdensity`` + times of the cosmological critical density. + + Parameters + ---------- + mass : float, `~numpy.ndarray` + Total mass of the cluster + Unit: [Msun] + overdensity : float + The times of density over the cosmological critical density, + e.g., 200, 500. + z : float, `~numpy.ndarray`, optional + Redshift + Default: 0.0 (i.e., present day) + + Returns + ------- + radius : float, `~numpy.ndarray` + Unit: [kpc] + """ + rho = COSMO.rho_crit(z) # [g/cm^3] + r = (3*mass*AUC.Msun2g / (4*np.pi * overdensity * rho))**(1/3) # [cm] + return r * AUC.cm2kpc # [kpc] + + def radius_virial(mass, z=0.0): """ Calculate the virial radius of a cluster at a given redshift. @@ -132,9 +159,7 @@ def radius_virial(mass, z=0.0): Unit: [kpc] """ Dc = COSMO.overdensity_virial(z) - rho = COSMO.rho_crit(z) # [g/cm^3] - R_vir = (3*mass*AUC.Msun2g / (4*np.pi * Dc * rho))**(1/3) # [cm] - return R_vir * AUC.cm2kpc # [kpc] + return radius_overdensity(mass, overdensity=Dc, z=z) def radius_stripping(M_main, M_sub, z, f_rc=0.1, beta=0.8): @@ -385,7 +410,7 @@ def velocity_impact(M_main, M_sub, z=0.0): ---------- Ref.[cassano2005],Eq.(9) """ - eta_v = 4 * (1 + M_main/M_sub) ** 0.333333 + eta_v = 4 * (1 + M_main/M_sub) ** (1/3) R_vir = radius_virial(M_main, z) * AUC.kpc2cm # [cm] vi = np.sqrt(2*AC.G * (1-1/eta_v) * (M_main+M_sub)*AUC.Msun2g / R_vir) # [cm/s] |