  The National Ignition Facility at Lawrence Livermore National Laboratory uses
$^{86}$Kr as a diagnostic tool to measure the neutron flux produced by fusion
reactions. As krypton is chemically inert, it can be implanted directly into
the fuel capsule, and the reaction products can be measured to determine the
flux of fusion neutrons. $^{86}$Kr cross sections also provide model
constraints for the $^{85}$Kr branching point in the s-process and the neutron
flux in stars. In this work, experimental data on the neutron production,
radiative capture, inelastic scattering, and total cross sections of $^{86}$Kr
were used in conjunction with the fast region nuclear reaction code EMPIRE and
a new resonance-region evaluation to produce a new evaluation of
neutron-induced reactions on $^{86}$Kr. For the EMPIRE calculations, we fitted
the optical model potential up to 12 MeV to simultaneously reproduce the
experimental data for the total cross section and the main inelastic gamma
transition from the $2^+$ state to the $0^+$ ground state. For energies above
12 MeV, due to large fluctuations and uncertainties in the total cross section
data, we preferred to adopt the Koning-Delaroche global spherical optical model
potential. With these models and corrections to the structure of $^{86}$Kr, the
evaluated cross sections matched the experimental data. The new evaluation has
been submitted for incorporation in the next release of the ENDF/B nuclear
reaction library.
