Woodruff School of Mechanical Engineering
Nuclear & Radiological Engineering and Medical Physics Programs
Nuclear Data Program at ORNL in Support of Nuclear Science Applications
Dr. Luiz Leal
Oak Ridge National Laboratory
Friday, September 17, 2010 at 11:00:00 AM
Boggs Building, Room 3-47 (3rd Floor)
Dr. Farzad Rahnema
The United States Nuclear Data Library ENDF/B-VII was released for use in diverse applications in the nuclear data field. This database is a collection of nuclear data evaluations performed in the United States and abroad, in the energy range from thermal up to several million electron volts. The data evaluation process is generally based on analysis and evaluation of energy- and angle-differential measurements performed by neutron time-of-flight techniques using linear accelerators as pulsed neutron sources, as for instance the Oak Ridge Electron Linear Accelerator (ORELA) located at the Oak Ridge National Laboratory (ORNL). Sophisticated computer codes such as SAMMY or EMPIRE are used for the evaluations to determine the best fit of theoretical cross section to experimental data. Many resonance evaluations done at ORNL have been included in the ENDF library. Examples are the 235U, 238U, and 232Th resonance evaluations. The presentation will describe (1) The methodology used at ORNL to evaluate differential nuclear data in both the resolved and the unresolved resonance energy regions, (2) The role of the integral data for validating the evaluation, (3) Data uncertainty propagation in the final keff calculations.
Luiz Leal: distinguished scientist working in the Nuclear Data and Criticality Safety Group of the Nuclear Science and Technology Division. PhD from the University of Tennessee (1990)
Refreshments will be served.