-134 has a half-life
of 2.0652 years. It is produced both directly (at a very small yield) as a fission product
, but not via beta decay
of other fission product nuclides
of mass 134, since beta decay stops at stable Xe-134
. It is also produced via neutron capture
from nonradioactive Cs-133
(neutron capture cross section
) which is a common fission product.
The combined yield of Cs-133 and Cs-134 is given as 6.7896%. The proportion between the two will change with continued neutron irradiation. Cs-134 also captures neutrons with a cross section of 140 barns, becoming long-lived radioactive Cs-135.