# 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.