qspec.f_recoil  (  f ,  m  )[source]

The change of a transition frequency of an atom at rest $\delta f = hf^2 / (2mc^2)$ due to the absorption of a photon with frequency $f$.

Parameters:

farray_like

The frequency of light in the atoms rest frame (MHz).

marray_like

The mass $m$ of the atom (u).

Returns:

outndarray

The change of the transition frequency $\delta f$ (MHz).