Scintillating-fiber-block detector for studying double-strangeness nuclei

Scintillating-fiber-block detectors have been constructed using <f>0.5 mm</f> square fibers for the KEK-PS E373 experiment, which searches for double-strangeness nuclei. The main aim of the detector is to measure the energies of protons and pions produced from decay of double- or single-hypernuclei using their ranges. It is also used to detect <f>Λ</f> hyperons or the <f>H</f>-dibaryon, and to make event selection. The performance of the detectors was studied with low-energy proton and pion beams as well as minimum-ionizing particles. The energy resolution determined by the range measurements was <f>0.86 MeV</f> for <f>37 MeV π−</f>''s and <f>1.4 MeV</f> for <f>47 MeV</f> protons. The excellent capability of <f>π/p</f> separation has been also demonstrated. [Copyright &y& Elsevier]