barak.absorb.logN_from_tau_peak¶
- barak.absorb.logN_from_tau_peak(tau, b, wa0, osc)[source]¶
Calculate the column density for a transition given its width and its optical depth at line centre.
Parameters : tau : array_like
Optical depth at line centre.
b : float
b parameter in km/s.
wa0 : float
Rest wavelength of the transition in Angstroms.
osc : float
Transition oscillator strength.
Returns : logN : ndarray, or scalar if tau is scalar
log10 of column density in cm^-2
See also