Calcium has a resonant transition at 422.7 nm the excited state has a lifetime of 4.5 ns, due only to fluorescence to the ground state. ignore possible degeneracies in the energy levels calculate:
the excited state energy in joules and in ev
the einstein coefficient for spontaneous emission, a
the einstein coefficient for absorption, b
the oscillator strength the maximum extinction coefficient.
the maximum absorption cross section
the transition dipole moment