ELSEVIER Nuclear Instruments and Methods in Physics Research A 404 (1998) 157F 165 zyxwvutsrqponmlkjihgfedcbaZYXW NUCLEAR INSTRUMENTS 6kMETNoDs IN zyxwvutsrqponmlkjihg PNYSICS RESEARCN SectIon A Properties of the YAP : Ce scintillator M. Moszyhski”,*, M. Kapustab, D. Wolski”, W. Klamra”, B. Cederwall’ zyxwvutsrqponmlkjihgf a Soltan Institute for Nuclear Studies, PL 05-400 Swierk-Otwock. Poland ‘Institute of Experimental Physics, Universit?, of Warsaw. Hoia 69, PL 00-681 Warsaw, Poland ‘Department of Physics, Royal Institute of Technology, Frescati, S-104 05, Stockholm, Sweden Received 22 April 1997; received in revised form 29 August 1997 zyxwvutsrqponmlkjihgfedcbaZYXWV Abstract Light yield, light pulse shape due to y-rays and a-particles, energy and time resolutions for a 10 x 10 x 5 zyxwvutsrqponml mm3 YAP crystal coupled to the XP2020Q photomultiplier were studied. The measured light output of 17 000 + 850 photons/MeV includes a correction for the calibrated quantum efficiency of the XP202OQ. The fast component of the light pulse with the decay time constant of 26.7 + 0.12 ns also shows a finite rise time described approximately by the time constant of 380 f 45 ps. The YAP crystal which was studied exhibited an energy resolution of 5.7% for 662 keV y-rays from a ‘37Cs source. This very good energy resolution is due to a low intrinsic energy resolution of 3.4%. These characteristics, together with a good time resolution for ‘j°Co y-rays of 160 ps measured at the threshold of 1 MeV, suggest a broad range of applications for the YAP scintillator. 0 1998 Elsevier Science B.V. All rights reserved. Ke~wo&: Scintillation detectors; Ce doped scintillators; Energy resolution; Fast timing 1. Introduction The last few years have seen renewed effort to develop new scintillation materials characterized by a high light output, a fast light pulse and a good detection efficiency for nuclear radiation. A recent study [l] identifies several crystalline compounds as potential new scintillator materials. Among the number of recently proposed new inorganic scintillators [2] the YAP : Ce (yttrium aluminum perovskite, YA103) is of a special inter- est in many applications. According to Refs. [3-73, *Corresponding author. Tel.: + 48 22 779 9531; fax: + 48 22 779 3481; e-mail: marek@sunp3.cyf.gov.p1. YAP : Ce is characterized by a high light output of 40% relative to NaI(Tl), a short decay time con- stant of 25 ns and a moderate efficiency for y-ray detection (density of 5.37 g/cm3, and atomic num- ber of yttrium, Z = 39). These properties of YAP and the fact that the peak of its emission spectrum, at 370 nm, is well coupled with the sensitivity of typical photomultipliers suggest potential applica- tions of YAP in y-ray spectroscopy, nuclear medi- cine, etc. It is important to note that, according to Refs. [8,9] the energy resolution of YAP is compa- rable to that of NaI(T1) and CsI(T1) with a photo- diode. For YAP, this is because the light yield is almost independent of the energy deposited by gamma rays in the crystal [8]. This light yield proportionality is not common for majority of the 0168-9002/98/$19.00 0 1998 Elsevier Science B.V. All rights reserved PI1 SO1 68-9002(97)01 11 5-7