New measurement system for on line in core high-energy neutron flux monitoring in materials testing reactor conditions

Geslot, B.; Vermeeren, L.; Filliatre, P.; Lopez, A. Legrand; Barbot, L.; Jammes, C.; Bréaud, S.; Oriol, L.; Villard, J.-F.
March 2011
Review of Scientific Instruments;Mar2011, Vol. 82 Issue 3, p033504
Academic Journal
Flux monitoring is of great interest for experimental studies in material testing reactors. Nowadays, only the thermal neutron flux can be monitored on line, e.g., using fission chambers or self-powered neutron detectors. In the framework of the Joint Instrumentation Laboratory between SCK-CEN and CEA, we have developed a fast neutron detector system (FNDS) capable of measuring on line the local high-energy neutron flux in fission reactor core and reflector locations. FNDS is based on fission chambers measurements in Campbelling mode. The system consists of two detectors, one detector being mainly sensitive to fast neutrons and the other one to thermal neutrons. On line data processing uses the CEA depletion code DARWIN in order to disentangle fast and thermal neutrons components, taking into account the isotopic evolution of the fissile deposit. The first results of FNDS experimental test in the BR2 reactor are presented in this paper. Several fission chambers have been irradiated up to a fluence of about 7 × 1020 n/cm2. A good agreement (less than 10% discrepancy) was observed between FNDS fast flux estimation and reference flux measurement.


Related Articles

  • Characterization of the neutron flux gradients in typical irradiation channels of a TRIGA Mark II reactor. Jaćimović, R.; Stibilj, V.; Benedik, L.; Smodiš, B. // Journal of Radioanalytical & Nuclear Chemistry;Sep2003, Vol. 257 Issue 3, p545 

    The neutron distribution in a defined volume (gradient) for different matrices (air, water, cellulose, biological material and silicon dioxide) in two typical irradiation channels (pneumatic tube (PT) and IC40-channel in the carousel facility) in the TRIGA Mark II reactor at the Jožef Stefan...

  • Neutron flux and associated k0 parameters in the RPI after the last configuration change. Mustra, C.O.; Freitas, M.C.; Almeida, S.M. // Journal of Radioanalytical & Nuclear Chemistry;Sep2003, Vol. 257 Issue 3, p539 

    The Portuguese Research Reactor (RPI) is a 1 MW swimming pool type reactor, operating since the early 1960s. The fuel is MTR type, with flat plates of U-Al alloy enriched to 93% in 235U. As the core configuration changed in April 2000, it became essential to characterise the neutron field in the...

  • High aspect ratio composite structures with 48.5% thermal neutron detection efficiency. Shao, Q.; Voss, L. F.; Conway, A. M.; Nikolic, R. J.; Dar, M. A.; Cheung, C. L. // Applied Physics Letters;2/11/2013, Vol. 102 Issue 6, p063505 

    The pillar structured thermal neutron detector is based on the combination of high aspect ratio silicon p-i-n pillars surrounded by the neutron converter material 10B. By etching high aspect ratio pillar structures into silicon, the result is a device that efficiently absorbs the thermal neutron...

  • Development of a thermal neutron detector based on scintillating fibers and silicon photomultipliers. Barbagallo, Massimo; Cosentino, Luigi; Greco, Giuseppe; Montereali, Rosa Maria; Pappalardo, Alfio; Scirè, Carlotta; Scirè, Sergio; Vincenti, Maria Aurora; Finocchiaro, Paolo // Review of Scientific Instruments;Sep2010, Vol. 81 Issue 9, p093503 

    We propose a technique for thermal neutron detection, based on a 6Li converter placed in front of scintillating fibers readout by means of silicon photomultipliers. Such a technique allows building cheap and compact detectors and dosimeters, thus possibly opening new perspectives in terms of...

  • Determination of α and f for k0-NAA in irradiation sites with high thermalized neutrons. Ho Manh Dung; Sasajima, Fumio // Journal of Radioanalytical & Nuclear Chemistry;Sep2003, Vol. 257 Issue 3, p509 

    At the irradiation sites in a research reactor where neutrons are well thermalized, the "bare" irradiation methods for a and f determinations that are incorporated in the KAYZERO®/SOLCOI® v4.0 package seem to be unworkable. It is a fact that when carrying out the determination of a and f...

  • Position-sensitive thermal neutron detector with [sup 6] Li-foil converter coupled to wire chambers. Friedrich, H.; Dangendorf, V.; Bräuning-Demian, A. // Applied Physics A: Materials Science & Processing;Dec2002 Supplement, Vol. 74 Issue 6, ps124 

    A two-dimensional position-sensitive thermal neutron detector is presented which is based on a thin foil acting as a neutron converter. In a metallic [sup 6]Li foil 135 μm thick, neutrons interact with [sup 6]Li and produce tritons and αparticles. Escaping charged particles are detected on...

  • Characterization of the Dalhousie University SLOWPOKE-2 reactor for k0-NAA and application to medium-lived nuclides. Acharya, R.; Chatt, A. // Journal of Radioanalytical & Nuclear Chemistry;Sep2003, Vol. 257 Issue 3, p525 

    The neutron spectra of one outer (#10) and two inner (#2 and #3) sites of the Dalhousie University SLOWPOKE-2 reactor (DUSR) have been calibrated for the k0-based neutron activation analysis (k0-NAA). The parameters determined include the cadmium ratio (RCd), epithermal neutron flux shape factor...

  • INAA of fluorine in plastics using the medium-flux McMaster Nuclear Reactor. Hancock, R. G. V.; Pidruczny, A. E.; Johnson, J. M. // Journal of Radioanalytical & Nuclear Chemistry;Jan2007, Vol. 271 Issue 1, p203 

    The fluorine contents of plastics, ranging from about 20 μg·g−1 to 66%, may be measured instrumentally using a conventional research nuclear reactor, an automated sample irradiation and counting system, and a set of well-calibrated, in-house, fluorine standards. Plastics with low to...

  • Exit reactor Thetis/Ghent (1967—2003): A recollection of its significant contribution to NAA and its leading role in the development of the k0-standardization. de Corte, F. // Journal of Radioanalytical & Nuclear Chemistry;Jan2007, Vol. 271 Issue 1, p37 

    After 36 years of operation, reactor Thetis at the Institute for Nuclear Sciences (Ghent University) was decommissioned in December 2003. On this occasion, a survey is presented of the characteristics and features of Thetis, which were opening the way to its significant contribution to NAA and...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics