Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10715744 | Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment | 2011 | 10 Pages |
Abstract
The fission chambers that provide in-core measurements of the neutron flux in nuclear reactors are also sensitive to the γâray flux. According to experimental data, this contribution can be dominant in current mode. We present a calculation route, relying on a description of the physical phenomena, that compute the γâray signal in a fission chamber, coming directly from the γâray flux, and indirectly from the neutron flux and activated structures. We use it in a working example for which we show that the main contribution of the γâray flux to the signal comes from the interaction of the γârays with the electrodes. The relative contribution of gammas created by neutron interactions in the detector is small. The comparison of this example with experimental results yields a good qualitative agreement: the γâray signal may dominate in current mode, but is effectively suppressed in fluctuation mode. This calculation route will be useful for the design of fission chambers to be operated under high neutron and γâray flux.
Related Topics
Physical Sciences and Engineering
Physics and Astronomy
Instrumentation
Authors
P. Filliatre, L. Vermeeren, C. Jammes, B. Geslot, D. Fourmentel,