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:
| 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_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:
| 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.