Hitoshi Sugimura Kyoto University (For E03 collaboration)
SNU Kiyoshi Tanida Ryuta Kiuchi Joo Chang Woo JAEA Ken’ichi Imai Hiroyuki Sako Susumu Sato KyotoU Hitoshi Sugimura Satoshi Adachi Hidemitsu Asano RCNP Tomoaki Hotta
Fe K-K- K+K+ 1.8GeV/c p Fe Ξ-Ξ- X-ray Ge-Detector Strong Interaction makes Energy Shift We detect X-ray from Ξ-atom by using Ge-detector for the first time. Energy shift provides information of ΞN interaction. Fe Ξ-Ξ-
K-K- K+K+ 1.8GeV/c p Fe Ξ-Ξ- Ξ-Ξ- X-ray Ge-Detector Strong Interaction makes Energy Shift 1-step,We detect X-ray by using Ge-detector. How to detect X-ray from xi atom is first challenge And 2-step make sure that how much energy shift. Make us information to ΞA interaction Expected Energy Shift (Simulation)
Target SSD SSD measures Ξ track and dE/dx to select slow Ξ so that better S/N ratio will be obtained for stopping Ξ. K-K- K+K+ KURAMA magnet Hyperball-J target K-K-
Thickness ~300um Effective area 6cmx6cm Pitch 80um x 768 strips Read out chip : APV25 128ch readout /1chip Shaping time 50nsec Serial Data Transfer Radiation tolerance checked up to 3x10 14 protons /cm 2 At 10 8 Hz beam, efficiency is accomplished up to 96%
K 計 12 面 768ch SSD Target (inside of cryostat)
Reconstruct pulse height by wave form analysis. We have achieved SNR>10 MIP signal Noise level S/N= =17.0 Reconstruct Hit Timing If 10 7 Hz beam, probability accidental hit is 13.6% Good enough to identify ghost tracks. σ=3.61ns time S/N
SSD has been developed for E03 which detect X-ray from Xi atom for the first time. SSD has been tested at J-PARC K1.8 beamline. We have obtained S/N = 17 and time resolution is 3.61ns which is sufficient for E03 experiment.
a new Ge detector array Hyperball2 ( ε ~4 % for 1 MeV ) can not be due to high count rate & radiation damage Need new Ge detector array → Need new Ge detector array Lower half of Hyperball-J PWO counter Ge detector Pulse-tube cooler Target Features Radiation-hard Ge detector → Mechanical cooling Fast background suppressor → PWO counter Pulse-shape readout and analysis Adjustable detector geometry Large photo-peak efficiency → ε ~6.1 MeV with 32 Ge detectors Remotely controlled and monitored
signal