be metal LANL EVAL-apr93 MACFARLANE
ref. 3 (1994) DIST-MAY10 20100309
----JENDL-4.0 MATERIAL 26
-----THERMAL NEUTRON SCATTERING DATA
The data were taken from ENDF/B-VI.8.
temperatures = 296, 400, 500, 600, 700, 800, 1000, 1200
this evaluation was generated at the los alamos national
laboratory (apr 1993) using the leapr code. the physical
model is very similar to the one used at general atomic
in 1969 to produce the original endf/b-iii evaluations
(see ref. 1). tighter grids and extended ranges for alpha
and beta were used. a slightly more detailed calculation
of the coherent inelastic scattering was generated. of
course, the various constants were updated to agree with
the endf/b-vi evaluation of be.
the phonon dispersion curves were fitted by Schmunk et al
using a model of central forces that extend to the fifth
nearest neightbors (ref 2). the phonon spectrum corresponding
to this model was calculated by the root sampling method,
and then used to compute s(alpha,beta). the coherent elastic
scattering cross section was computed using the known lattice
3tructure (hexagonal close-packed) and the debye-waller
integrals from the lattice dynamics model.
1. j.u.koppel and d.h.houston, reference manual for endf thermal
neutron scattering data, general atomic report ga-8774
revised and reissued as endf-269 by the national nuclear
data center, july 1978.
2. r.e.schmunk, r.m.brugger, p.d.randolph, and k.a.strong,
phys. rev. 128,562 (1962).
3. r.e.macfarlane, new thermal neutron scattering files for
endf/b-vi release 2, los alamos national laboratory report
LA-12639-MS (ENDF-356) March 1994.