I found in the background page that the softening length for stars particles in TNG100-1 at z=0 is 0.74 kpc. Where can I get the softening length for higher redshifts?

Dylan Nelson

31 Aug '20

Gravitational softenings for stars and DM are in comoving kpc until z=1 after which they are fixed to their z=1 values, such that at z=0 they have half the softening length they would have had if the comoving evolution had been kept. Softenings for gas cells are adaptive, set to 2.5 times the current [comoving] cell radius.

So the softenings at z=1 are the same as at z=0, while for z>1, they become fixed in comoving units (increasingly smaller in physical units towards high redshift).

Hi,

I was wondering what the spatial resolution (softening length) of the TNG100 simulation is?

Cheers,

Aaron

Hi Aaron,

You can find these numbers on the first table of the Project Description page.

Dear Dylan,

I found in the background page that the softening length for stars particles in TNG100-1 at z=0 is 0.74 kpc. Where can I get the softening length for higher redshifts?

Gravitational softenings for stars and DM are in comoving kpc until z=1 after which they are fixed to their z=1 values, such that at z=0 they have half the softening length they would have had if the comoving evolution had been kept. Softenings for gas cells are adaptive, set to 2.5 times the current [comoving] cell radius.

So the softenings at z=1 are the same as at z=0, while for z>1, they become fixed in comoving units (increasingly smaller in physical units towards high redshift).

Thank you Dylan!