Scintillating properties of today available lead tungstate crystals

Abstract

In the context of the ClearMind project, we measured the scintillating\nproperties, as induced from from gamma ray interactions, of today available\nPbWO4 crystal. We measured scintillation s yields and time constants by\nmeasuring the signal shape measured on a fast photo-multiplier and\ndeconvoluting it from the instrumental effects. For the doped crystals at room\ntemperature, we measured a fast scintillation component, with time constants of\n2 ns, 55 percent of the total light yield, and a slow component of 6 ns. We\nobserve a significant increase of the light yield for the slow component when\nthe temperature decreases and simultaneous increase of the time constants, but\nno increase in the fast component light yield. Our measurements reproduce the\nmain qualitative features of PbWO4 crystals quoted in the literature.\nQuantitatively though, we measured significantly shorter time constants and\nlarger light yields. This is explained by a rigorous treatment of the\ninstrumental contributions in the measurements. Results are discussed and\nprospect for future developments, tailored for the ClearMind project, are\npresented.\n