A high resolution Timing Counter for the MEG II experiment

作者：De Gerone M^*; Bevilacqua A; Biasotti M; Boca G; Cattaneo P W; Gatti F; Nishimura M; Ootani W; Pizzigoni G; Rossella M; Shibata N; Siccardi F; Simonetta M; Uchiyama Y; Yoshida K

来源：Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment , 2016, 824: 92-95.

DOI：10.1016/j.inma.2015.11.022

• Scintillation counter
• Time-of-flight counter

The development of a Timing Counter detector designed for the MEGII upgrade of the MEG experiment, which strives to improve the sensitivity on the mu(+) -> e(+) gamma decay of an order of magnitude, is presented. It is based on two sets of counters (sectors) arranged on a semi-cylindrical structure; each sector consists of 256 counters. Each counter consists of tile of fast scintillator with a dual-side read-out based on SiPM arrays in series connection. The high granularity has two advantages: optimized size for achieving high resolution (75 ps) for the single counter, and a signal e(+) crosses several counters, so that resolution improves by averaging multiple time measurements. A prototype has been built and tested both in BTF and PSI facilities in order to prove the multi-hit scheme in MEG-like beam conditions. A 35 ps resolution with eight hits has been obtained with a e(+) beam at 100 kHz. The first sector will be tested in the MEG II pre-engineering run planned at the end of 2015.

• 出版日期2016-7-11