diff options
Diffstat (limited to 'fg21sim/extragalactic/clusters/halo.py')
| -rw-r--r-- | fg21sim/extragalactic/clusters/halo.py | 30 |
1 files changed, 15 insertions, 15 deletions
diff --git a/fg21sim/extragalactic/clusters/halo.py b/fg21sim/extragalactic/clusters/halo.py index 1d9c9aa..5df47cd 100644 --- a/fg21sim/extragalactic/clusters/halo.py +++ b/fg21sim/extragalactic/clusters/halo.py @@ -75,11 +75,11 @@ class RadioHalo: Description ----------- - 1. Calculate the merger crossing time (t_cross; ~1 Gyr); - 2. Calculate the diffusion coefficient (Dpp) from the systematic + 1. Calculate the turbulence persistence time (tau_turb; ~<1 Gyr); + 2. Calculate the diffusion coefficient (D_pp) from the systematic acceleration timescale (tau_acc; ~0.1 Gyr). The acceleration - diffusion is assumed to have an action time ~ t_cross (i.e., - only during merger crossing), and then been disabled (i.e., + diffusion is assumed to have an action time ~ tau_turb (i.e., + only during turbulence persistence), and then is disabled (i.e., only radiation and ionization losses later); 3. Assume the electrons are constantly injected and has a power-law energy spectrum, determine the injection rate by further assuming @@ -192,16 +192,16 @@ class RadioHalo: @property @lru_cache() - def time_crossing(self): + def time_turbulence(self): """ - The time duration of the sub-cluster crossing the main cluster, - which is also used to approximate the merging time, during which - the turbulence acceleration is regarded as effective. + The time duration the merger-induced turbulence persists, which + is used to approximate the effective turbulence acceleration + timescale. Unit: [Gyr] """ - return helper.time_crossing(self.M_main, self.M_sub, - z=self.z_merger) + return helper.time_turbulence(self.M_main, self.M_sub, + z=self.z_merger, configs=self.configs) @property def radius_virial_obs(self): @@ -706,10 +706,10 @@ class RadioHalo: NOTE ---- Considering that the turbulence acceleration is a 2nd-order Fermi - process, it has only an effective acceleration time of several 1e8 - years. Therefore, the turbulence is assumed to only accelerate - the electrons during the merging period, i.e., the acceleration - timescale is set to be infinite after "t_merger + time_cross". + process, it has only an effective acceleration time ~<1 Gyr. + Therefore, only during the period that strong turbulence persists + in the ICM that the turbulence could effectively accelerate the + relativistic electrons. WARNING ------- @@ -745,7 +745,7 @@ class RadioHalo: ---------- Ref.[donnert2013],Eq.(15) """ - if (t < self.age_merger) or (t > self.age_merger+self.time_crossing): + if (t < self.age_merger) or (t > self.age_merger+self.time_turbulence): # NO acceleration (see also the above NOTE and WARNING!) tau_acc = 10 # [Gyr] else: |