  We have measured the thermal neutron capture cross section for w-180 nucleus.
There is only one previous data on this cross section with a value of 30
$^{+300%}_{-100%}$ barn. To consider w-181 as a low energy neutrino source, the
thermal neutron capture cross section should be measured more precisely to
estimate the production rate of w-181 inside a nuclear reactor. We measured the
cross section of w-180 with a natural tungsten foil and obtained a new value of
21.9 $\pm$ 2.5 barn
