Ultra-Fast Timing with Plastic Scintillators

As precursor to HISPEC, the upcoming PreSPEC campaign incorporates the commissioning of the first version of the LYCCA (Lund-York-Cologne-CAlorimeter) detector system called LYCCA-0. The LYCCA detector is a Time-of-Flight (ToF), ∆E, E set-up designed to unambigiously identify nuclear reaction products by their mass A, and charge Z . For this to be possible up to masses around A = 100, the total time resolution of the ToF measurement should be on the order of 100 ps FWHM or better [1]; comprised of 50 ps and 80 ps FWHM for the start and stop detctor, respectively. Mainly two timing options are deemed viable; polycrystaline CVD diamond detectors and fast plastic scintillators. In the LYCCA-0 set-up the diamond detectors are to be tested as ToF-start detector, while a large-area fast plastic scintillator is to give the ToF-stop signal. This report outlines first results from proof of principle tests of the fast plastic scintillator investigated both in the laboratory using a laser and in-beam during a test experiment at the FRS [2].