[yt-dev] Issue #971: yt-3.0 gadget InternalEnergy field unit (yt_analysis/yt)

[Junhwan Choi]

New issue 971: yt-3.0 gadget InternalEnergy field unit
https://bitbucket.org/yt_analysis/yt/issue/971/yt-30-gadget-internalenergy-field-unit

Junhwan Choi:

Hi yt developers,

I would like to file a bug related with gadget(spy) field.
I (and Nathan Goldbaum) found that the InternalEnergy field in yt/frontends/sph/fields.py is read as dimensionless.
Indeed, the unit of the gadget InternalEnergy is  Velocity_unit**2.
For example, if the unit is defined as follow:

unit_base = {'UnitLength_in_cm'         : 3.08568e+21,
             'UnitMass_in_g'            :   1.989e+43,
             'UnitVelocity_in_cm_per_s' :      100000}

The Internal Energy unit is (km/s)**2

If it is possible that I would like to ask to set up the temperature field for gadget dataset.
Indeed, the gadget output only generates the InternalEnergy and temperature need to be estimated from the InternalEnergy and chemical abundance (if there are).
Although it is possible to generate the derived temperature field, the temperature is very basic quantity and it may need to computed for both particle and cell.

Thank you,
Junhwan