What is the time resolution of BH_Mdot in TNG simulations?
Suin Matsui
2 Jul
I would like to ask about the time scale over which the SubhaloBHMdot field is calculated in the TNG simulations.
The documentation says this is the "instantaneous" black hole accretion rate.
Does this mean it is calculated at each hydrodynamical timestep?
If so, what is the typical duration of such a timestep in the TNG100 or TNG300 simulations (e.g., 10⁴–10⁵ years)?
Dylan Nelson
2 Jul
Yes, this is a value calculated at the current timestep / whatever timestep the BH particle was last active.
I can't quote a typical timestep, particularly since the simulation uses individual adaptive timesteps (every particle/cell can have a different timestep). The timesteps you mention are probably OK to within an order of magnitude, in the centers of galaxies.
Suin Matsui
19h
Thank you very much for your clear explanation.
I understand now that the simulation uses individual adaptive timesteps where each particle or cell can have a different timestep — that was very informative.
I appreciate your help!
I would like to ask about the time scale over which the SubhaloBHMdot field is calculated in the TNG simulations.
The documentation says this is the "instantaneous" black hole accretion rate.
Does this mean it is calculated at each hydrodynamical timestep?
If so, what is the typical duration of such a timestep in the TNG100 or TNG300 simulations (e.g., 10⁴–10⁵ years)?
Yes, this is a value calculated at the current timestep / whatever timestep the BH particle was last active.
I can't quote a typical timestep, particularly since the simulation uses individual adaptive timesteps (every particle/cell can have a different timestep). The timesteps you mention are probably OK to within an order of magnitude, in the centers of galaxies.
Thank you very much for your clear explanation.
I understand now that the simulation uses individual adaptive timesteps where each particle or cell can have a different timestep — that was very informative.
I appreciate your help!