Program - Brookhaven National Laboratory

processing evaluated data in a “pipeline” for end-use applications; and running simulations with custom
collections of nuclear data input. First-generation versions of many of these tools already exist online and
will be discussed, along with an outlook for the future of cloud computing in this field and how you can
contribute at ndc3.net. This work is supported by the US DOE Office of Nuclear Physics.
Session FC Covariances
Tuesday March 5, 2013
Room: Empire East at 10:30 AM
FC 1 10:30 AM
Full Bayesian Evaluation Technique for Angle-Differential Data
G. Schnabel, H. Leeb
Atominstitut, TU Wien, Wiedner Hautpstrasse 8-10, 1040 Vienna, Austria
D. Neudecker
T-2, Theoretical Division, Nuclear and Particle Physics, Astrophysics & Cosmology, Los Alamos
National Laboratory, Los Alamos, NM 87545, USA
The Full Bayesian Evaluation Technique [1] is a direct application of Bayesian statistics to nuclear data
evaluation. It is characterized by a careful determination of the prior uncertainties related to modelling and
is therefore well suited for evaluations strongly based on nuclear models. In its original version [1] the Full
Bayesian Evaluation Technique was limited to angle-integrated cross sections. Thus information provided
by angle-differential data has been ignored. In this contribution the evaluation method is extended to angledifferential
data. The major problem is the large number of parameters involved. We present a proper
parametrisation of the angular distributions with a reasonable number of parameters. Most important
is the correlation of the parameters with the zero order Legendre coefficient which has a direct impact
on angle-integrated cross section. Thus the information contained in angle-differential data affects the
angle-integrated cross sections and consequently also the complete evaluation. The formulation and the
properties of the method are discussed at different examples.
Corresponding author: H. Leeb
[1] H. Leeb, D. Neudecker, Th. Srdinko, Nucl. Data Sheets 109 (2008) 2762.
FC 2 11:00 AM
Advanced Uncertainty Quantification for Fission Observables
D. Neudecker, P. Talou, T. Kawano
Los Alamos National Laboratory, T-2, Theoretical Division, Nuclear and Particle Physics, Astrophysics
& Cosmology
F. Tovesson
Los Alamos National Laboratory, LANSCE-NS
Advances in nuclear technologies, and in particular the next-generation of nuclear reactors, require an
improved knowledge of different fission observables like e.g. prompt fission neutron spectra or fission cross
sections. To meet these demands, sophisticated models are being developed, and high-precision measurements
are undertaken at LANL such as the newly established time projection chamber at LANSCE. In
this contribution recent advances in the related evaluation methodology are presented which aim at an
improved quantification of uncertainties associated with experimental data as well as calculations. In the
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