TY  - JOUR
AU  - BRIKEN Collaboration (Tarifeño-Saldivia, A. et al
AU  - Tain, J. L.
AU  - Domingo-Pardo, C.
AU  - Agramunt, J.
AU  - Algora, A.
AU  - Morales, A. I.
AU  - Rubio, B.
AU  - Tolosa, A.
PY  - 2017
DA  - 2017//
TI  - Conceptual design of a hybrid neutron-gamma detector for study of beta-delayed neutrons at the RIB facility of RIKEN
T2  - J. Instrum.
JO  - Journal of Instrumentation
SP  - P04006 - 22pp
VL  - 12
PB  - Iop Publishing Ltd
KW  - Detector modelling and simulations I (interaction of radiation with matter
KW  - interaction
KW  - of photons with matter
KW  - interaction of hadrons with matter
KW  - etc)
KW  - Instrumentation for radioactive beams (fragmentation devices
KW  - fragment and isotope
KW  - separators incl. ISOL
KW  - isobar separators
KW  - ion and atom traps
KW  - weak-beam diagnostics
KW  - radioactive-beam ion sources)
KW  - Neutron detectors (cold
KW  - thermal
KW  - fast neutrons)
AB  - BRIKEN is a complex detection system to be installed at the RIB-facility of the RIKEN Nishina Center. It is aimed at the detection of heavy-ion implants, β-particles, γ-rays and β-delayed neutrons. The whole detection setup involves the Advanced Implantation Detection Array (AIDA), two HPGe Clover detectors and a large set of 166 counters of 3He embedded in a high-density polyethylene matrix. This article reports on a novel methodology developed for the conceptual design and optimisation of the 3He-tubes array, aiming at the best possible performance in terms of neutron detection. The algorithm is based on a geometric representation of two selected parameters of merit, namely, average neutron detection efficiency and efficiency flatness, as a function of a reduced number of geometric variables. The response of the detection system itself, for each configuration, is obtained from a systematic MC-simulation implemented realistically in Geant4. This approach has been found to be particularly useful. On the one hand, due to the different types and large number of 3He-tubes involved and, on the other hand, due to the additional constraints introduced by the ancillary detectors for charged particles and gamma-rays. Empowered by the robustness of the algorithm, we have been able to design a versatile detection system, which can be easily re-arranged into a compact mode in order to maximize the neutron detection performance, at the cost of the gamma-ray sensitivity. In summary, we have designed a system which shows, for neutron energies up to 1(5) MeV, a rather flat and high average efficiency of 68.6%(64%) and 75.7%(71%) for the hybrid and compact modes, respectively. The performance of the BRIKEN system has been also quantified realistically by means of MC-simulations made with different neutron energy distributions.
SN  - 1748-0221
UR  - http://arxiv.org/abs/1606.05544
UR  - https://doi.org/10.1088/1748-0221/12/04/P04006
DO  - 10.1088/1748-0221/12/04/P04006
LA  - English
N1  - WOS:000405067800006
ID  - BRIKENCollaborationTarifeno-Saldivia_etal2017
ER  -