Diffraction measurements with a boron-based GEM neutron detector

¹ Istituto di Fisica del Plasma (IFP-CNR) - Via Cozzi 53, 20125 Milano, Italy
² Dipartimento di Fisica, Università degli studi di Milano Bicocca - Piazza della Scienza 3, 20126 Milano, Itlay
³ STFC-ISIS Facility, RAL - OX11 0Q, Didcot, UK
⁴ INFN - Laboratori Nazionali di Frascati - Via Fermi 40, 0044 Frascati, Italy
⁵ INFN - Sezione di Milano-Bicocca - Piazza della Scienza 3, 20126 Milano, Italy

^(a) croci@ifp.cnr.it

Received: 24 April 2014
Accepted: 13 June 2014

Abstract

The research of reliable substitutes of ³He detectors is an important task for the affordability of new neutron scattering instrumentation for future spallation sources like the European Spallation Source. GEM (Gas Electron Multiplier)-based detectors represent a valid alternative since they can combine high-rate capability, coverage of up to area and good intrinsic spatial resolution (for this detector class it can be better than 0.5 mm). The first neutron diffraction measurements performed using a borated GEM detector are reported. The detector has an active area of and is equipped with a borated cathode. The GEM detector was read out using the standard ISIS Data Acquisition System. The comparison with measurements performed with standard ³He detectors shows that the broadening of the peaks measured on the diffractogram obtained with the GEM is 20–30% wider than the one obtained by ³He tubes but the active area of the GEM is twice that of ³He tubes. The GEM resolution is improved if half of its active area is considered. The signal-to-background ratio of the GEM is about 1.5 to 2 times lower than that of ³He. This measurement proves that GEM detectors can be used for neutron diffraction measurements and paves the way for their use at future neutron spallation sources.