  The 62Ni(n,gamma)63Ni(t_1/2=100+-2 yrs) reaction plays an important role in
the control of the flow path of the slow neutron-capture (s-) nucleosynthesis
process. We have measured for the first time the total cross section of this
reaction for a quasi-Maxwellian (kT = 25 keV) neutron flux. The measurement was
performed by fast-neutron activation, combined with accelerator mass
spectrometry to detect directly the 63Ni product nuclei. The experimental value
of 28.4+-2.8 mb, fairly consistent with a recent theoretical estimate, affects
the calculated net yield of 62Ni itself and the whole distribution of nuclei
with 62<A <90 produced by the weak s-process in massive stars.
