Speaker
Luca Galli
(INFN - Pisa)
Description
Cerium-doped lanthanum bromide (LaBr:Ce) is a scintillator that present very good energy and timing resolution. Its light yield is 1.5 times that of sodium iodide, yet its time constant is much shorter (20 ns). These properties, toghether with its high density and the presence of a 2.5 MeV self-activity line, make it a perfect candidate for a self-calibrating photon detector in the 50-100 MeV energy range as, for instance, in future experiments to search for lepton flavour violation as in µ→eγ or µ→e conversion. In the former a monochromatic 52.8 MeV γ-ray must be discriminated from a continuous background, while in the latter the signature is given by a monoenergetic positron of about 100 MeV.
While energy relolution was thoroughly investigated, timing resolution at several MeV presents some experimental challenge.
We measured the timing resolution of a 3'' x 3'' cylindrical BrLaCe crystal against a YAP detector read by an Hamamatsu fine mesh PMT by means of a nuclear reaction from a Cockcroft-Walton accelerator that produces coincident gamma rays in the 4.4 to 16 MeV range.
Preliminary results allow us to extrapolate the properties of a segmented gamma ray detector in the 50-100 MeV range.
Primary author
Dr
Giovanni Signorelli
(INFN Pisa)
Co-authors
Angela Papa
(Paul Scherrer Institut)
Donato Nicolò
(Università di Pisa)
Francesco Tenchini
(INFN & Università di Pisa)
Luca Galli
(INFN - Pisa)
Matteo De Gerone
(INFN Genova)
Dr
Simeone Dussoni
(INFN Genova)
