Table Atmospheres

When the atm_option control is set to 'table', MESA uses pre-computed tables from separate model atmosphere calculations to interpolate \(T_{\rm surf}\) and \(P_{\rm surf}\) values for the boundary conditions. The interpolations are peformed using \(T_{\rm eff}\) and \(\log g\) as independent variables. The atm_table control determines the choice of table, as follows:

The atm_table control

Value	Meaning
'photosphere'	Use model atmosphere tables computed for a range of metallicites, via a combination of PHOENIX (Hauschildt et al. 1999a,b) and Castelli & Kurucz (2003) treatments. Surface optical depth is defined so that \(T(\tau_{\rm surf}) = T_{\rm eff}\).
'tau_100'	Use model atmosphere tables computed for solar metallicites, via a combination of COND (Allard et al. 2001) and Castelli & Kurucz (2003) treatments. Surface optical depth is \(\tau_{\rm surf} = 100\).
'tau_10'	Same as 'tau_100', except that surface optical depth is \(\tau_{\rm surf} = 10\).
'tau_1'	Same as 'tau_100', except that surface optical depth is \(\tau_{\rm surf} = 1\).
'tau_1m1'	Same as 'tau_100', except that surface optical depth is \(\tau_{\rm surf} = 0.1\).
'WD_tau_25'	Use model atmospheres for cool white dwarfs, via Rohrmann et al. (2011, MNRAS, 411, 781) treatment. Surface optical depth is \(\tau_{\rm surf} = 25.12\).
'DB_WD_tau_25'	Use model atmospheres for hot(ter) white dwarrfs, provided by Odette Toloza based on Detlev Koester’s atmosphere code. Surface optical depth is \(\tau_{\rm surf} = 25.12\).

When any of these 'table' choices is used, it’s possible that the requested \(T_{\rm eff}\) and \(\log g\) lie outside the table range. When this happens, MESA can optionally switch to an alternative approach for evaluating \(T_{\rm surf}\) and \(P_{\rm surf}\). The atm_off_table_option control determines the alternative approach adopted, as follows:

The atm_off_table_option control

Value	Meaning
'T_tau'	Use the same \(T(\tau)\) approach as described in the T(tau) Atmospheres section. The atm_T_tau_relation and atm_T_tau_opacity controls (and others) are used in this case for the off-table evaluation.

If the atm_off_table_option control is left blank, an attempt to interpolate off the table will cause MESA to halt execution.