First tests of the applicability of $γ$-ray imaging for background discrimination in time-of-flight neutron capture measurements

D. L. Pérez Magán; L. Caballero-Ontanaya; C. Domingo-Pardo; J. Agramunt-Ros; F. Albiol; A. Casanovas; A. González; C. Guerrero; J. Lerendegui-Marco; A. Tarifeño-Saldivia; the n_TOF Collaboration

doi:10.1016/j.nima.2016.03.073

arXiv · 1510.02344

First tests of the applicability of $γ$-ray imaging for background discrimination in time-of-flight neutron capture measurements

D. L. Pérez Magán·L. Caballero-Ontanaya·C. Domingo-Pardo·J. Agramunt-Ros·F. Albiol·A. Casanovas·A. González·C. Guerrero·J. Lerendegui-Marco·A. Tarifeño-Saldivia·the n_TOF Collaboration

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Abstract

In this work we explore for the first time the applicability of using $γ$-ray imaging in neutron capture measurements to identify and suppress spatially localized background. For this aim, a pinhole gamma camera is assembled, tested and characterized in terms of energy and spatial performance. It consists of a monolithic CeBr$_3$ scintillating crystal coupled to a position-sensitive photomultiplier and readout through an integrated circuit AMIC2GR. The pinhole collimator is a massive carven block of lead. A series of dedicated measurements with calibrated sources and with a neutron beam incident on a $^{197}$Au sample have been carried out at n_TOF, achieving an enhancement of a factor of two in the signal-to-background ratio when selecting only those events coming from the direction of the sample.

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D. L. Pérez Magán, L. Caballero-Ontanaya, C. Domingo-Pardo, J. Agramunt-Ros, F. Albiol, A. Casanovas, A. González, C. Guerrero, J. Lerendegui-Marco, A. Tarifeño-Saldivia, the n_TOF Collaboration. 2015-10-14. First tests of the applicability of $γ$-ray imaging for background discrimination in time-of-flight neutron capture measurements. https://doi.org/10.1016/j.nima.2016.03.073

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