Author:
Kanno K.,Aoki K.,Arimizu D.,Ashikaga S.,Ebata K.,Honda R.,Ichikawa M.,Kajikawa S.,Kimura Y.,Kondo T.K.,Kyan S.,Morino Y.,Murakami H.,Murakami T.N.,Nakai W.,Nakasuga S.,Naruki M.,Nonaka T.,Noumi H.,Ogata N.,Ozawa K.,Sako H.,Sato S.,Sekimoto M.,Shirotori K.,Takahashi T.N.,Takaura Y.,Tatsumi R.,Tsukui K.,Yahiro K.,Yokkaichi S.
Abstract
Abstract
The J-PARC E16 experiment measures mass spectra of low-mass vector mesons,
ρ, ω, and ϕ, in nuclei via e
+
e
- decays. Vector mesons are produced in
pA reactions. A spectrometer with a large acceptance and a high-intensity beam up to 1
× 1010 protons per ∼2-sec duration pulse are utilized to collect a sufficient number
of vector mesons. We have developed a spectrometer, which has two types of electron
identification detectors: a hadron blind detector (HBD) and a lead-glass calorimeter.
Commissioning runs have been performed at the J-PARC high-momentum beam line. The HBD
successfully observed on average 11 ± 1 photoelectrons for an incident electron. We achieved
the pion rejection of 0.9 ± 0.2% with the electron detection efficiency of 61 ± 4% for
the HBD, which was consistent of the expected performance.
Subject
Mathematical Physics,Instrumentation