More information on Emission of Electromagnetic Radiation (pdf-file)
Transition probability 
for 
-ray emission
of electric (E 
) and magnetic (M ) multipole quanta
from an excited nuclear state 
into a lower-lying state 
:
Relation between the transition probablility and the reduced
transition probability 
.
are in units of 
, 
in MeV,
( 
are the nuclear level energies of the initial and final states,respectively),
in 
,
and 
in 
with 
.
Relation between the lifetime 
or half-life 
of an
excited nuclear state and the transition probabilities :
One has to sum over all final states into which level can decay
and over all multipoles in the transition 
.
is the usual total -pole conversion coefficient.
Relation between the reduced transition probability 
and the lifetime 
or half-life 
for
the special case of a pure E2 decay from an excited state to the ground state:
with and 
in sec, 
in MeV and B(E2) in 
.
