clusters/halo: Update time_turbulence() calculation

2 files changed, 10 insertions, 28 deletions

diff --git a/fg21sim/extragalactic/clusters/halo.py b/fg21sim/extragalactic/clusters/halo.py
index 273a611..2b2b719 100644
--- a/fg21sim/extragalactic/clusters/halo.py
+++ b/fg21sim/extragalactic/clusters/halo.py
@@ -197,9 +197,11 @@ class RadioHalo:
 
     def time_turbulence(self, t=None):
         """
-        The duration that the merger-induced turbulence persists, which
-        is used to approximate the lasting time of the effective turbulence
-        acceleration.
+        The duration that the compressive turbulence persists, which is
+        estimated as:
+            τ_turb ≅ L / v_impact = 2*R_turb / v_impact.
+        During this period, the merger-induced turbulence is regarded
+        to accelerate the relativistic electrons effectively.
 
         Unit: [Gyr]
         """
@@ -207,8 +209,11 @@ class RadioHalo:
         mass_main = self.mass_main(t=t_merger)
         mass_sub = self.mass_sub(t=t_merger)
         z_merger = COSMO.redshift(t_merger)
-        return helper.time_turbulence(mass_main, mass_sub, z=z_merger,
-                                      configs=self.configs)
+        vi = helper.velocity_impact(mass_main, mass_sub, z_merger)  # [km/s]
+        distance = 2 * self.injection_radius
+        uconv = AUC.kpc2km * AUC.s2Gyr  # [s kpc/km] => [Gyr]
+        time = uconv * distance / vi  # [Gyr]
+        return time
 
     def mach_turbulence(self, t=None):
         """
diff --git a/fg21sim/extragalactic/clusters/helper.py b/fg21sim/extragalactic/clusters/helper.py
index d8e231e..8eef6b9 100644
--- a/fg21sim/extragalactic/clusters/helper.py
+++ b/fg21sim/extragalactic/clusters/helper.py
@@ -406,29 +406,6 @@ def time_crossing(M_main, M_sub, z=0.0):
     return time
 
 
-def time_turbulence(M_main, M_sub, z=0.0, configs=CONFIGS):
-    """
-    The duration that the compressive turbulence persists, which is
-    estimated as:
-        τ_turb ≅ 2*d / v_impact,
-    where d ≅ L ≅ R_vir / 3,
-    and L is also the turbulence injection scale.
-    During this period, the merger-induced turbulence is regarded
-    to accelerate the relativistic electrons effectively.
-
-    Unit: [Gyr]
-    """
-    # Turbulence injection scale factor
-    key = "extragalactic/halos/f_lturb"
-    f_lturb = configs.getn(key)
-    R_vir = radius_virial(M_main+M_sub, z)  # [kpc]
-    distance = 2*R_vir * f_lturb
-    vi = velocity_impact(M_main, M_sub, z)  # [km/s]
-    uconv = AUC.kpc2km * AUC.s2Gyr  # [s kpc/km] => [Gyr]
-    time = uconv * distance / vi  # [Gyr]
-    return time
-
-
 def draw_halo(radius, nr=2.0, felong=None, rotation=None):
     """
     Draw the template image of one halo, which is used to simulate