Response functions of the 4π detector ORION to 10–70 MeV neutrons

• Published in: Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment Vol. 413; no. 2; pp. 312 - 320
• Main Authors: Périer, Y., Lott, B., Masri, Y.El, Galin, J., Keutgen, Th, Faou, J.H.Le, Morjean, M., Péghaire, A., Quednau, B.M., Tilquin, I.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 21.08.1998
• ISSN: 0168-9002; 1872-9576
• DOI: 10.1016/S0168-9002(98)00494-X

The neutron detection performances of the 4π ORION counter were investigated with monoenergetic neutron beams delivered by the Louvain-la-Neuve facility. Two responses are supplied by such a counter: a prompt response, arising from the slowing down of neutrons within the liquid scintillator contained in the detector, and a delayed response corresponding to the subsequent capture of the neutrons by Gd nuclei, with which the detector is loaded. Two experimental methods were used, allowing one to probe the responses for different neutron energies. Despite the large size of the detector, the prompt response is observed to be very similar to that exhibited by small cells. For both responses, a reasonable overall agreement is found between the data and the predictions of Monte-Carlo simulations. The timing resolution, of the order of 3 ns, makes this detector suitable for time-of-flight methods in applications requiring a high detection efficiency while accepting a moderate energy resolution.