Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Event-by-event study of prompt neutrons from 239Pu(n,f)   Employing a recently developed Monte Carlo model, we study the fission of
240Pu induced by neutrons with energies from thermal to just below the
threshold for second chance fission. Current measurements of the mean number of
prompt neutrons emitted in fission, together with less accurate measurements of
the neutron energy spectra, place remarkably fine constraints on predictions of
microscopic calculations. In particular, the total excitation energy of the
nascent fragments must be specified to within 1 MeV to avoid disagreement with
measurements of the mean neutron multiplicity. The combination of the Monte
Carlo fission model with a statistical likelihood analysis also presents a
powerful tool for the evaluation of fission neutron data. Of particular
importance is the fission spectrum, which plays a key role in determining
reactor criticality. We show that our approach can be used to develop an
estimate of the fission spectrum with uncertainties several times smaller than
current experimental uncertainties for outgoing neutron energies up to 2 MeV.

21
The categories of this paper are: adap-org
20
The categories of this paper are: acc-phys
29
The categories of this paper are: funct-an
24
The categories of this paper are: dg-ga
4
The categories of this paper are: cond-mat
32
The categories of this paper are: atom-ph
35
The categories of this paper are: mtrl-th
25
The categories of this paper are: patt-sol
28
The categories of this paper are: alg-geom
10
The categories of this paper are: q-bio
31
The categories of this paper are: ao-sci
18
The categories of this paper are: econ
14
The categories of this paper are: math-ph
6
The categories of this paper are: astro-ph
30
The categories of this paper are: q-alg
23
The categories of this paper are: solv-int