MBGEM: a stack of borated GEM detector for high efficiency thermal neutron detection

A new position-sensitive thermal neutron detector based on boron-coated converters has been developed as an alternative to today’s standard $^3\mathrm{He}$-based technology for application to thermal neutron scattering. The key elements of the development are the boron-coated GEM foils (Sauli in Nucl Instrum Methods Phys Res Sect A Accel Spectrom Detect Assoc Equip 386:531, 1997) that are used as a multi-layer neutron converter via the $^{10}\mathrm{B}(n,\alpha )^7\mathrm{Li}$ reaction together with an efficient collection of the produced secondary electrons. This paper reports the test performed on a 3 layers converter prototype coupled to a GEMPix detector (Murtas in Radiat Meas 138:106421, 2020), carried out in order to study the possibility to produce a large-scale multi-layer neutron detector capable to reach high detection efficiency with high spatial resolution and able to sustain the high neutron flux expected in the new neutron spallation source under development like the ESS.