実験報告書様式（一般利用課題・成果公開利用）

MLF	 Experimental Report

提出日 Date of Report

課題番号 Project No.

装置責任者 Name of responsible person

2014A0229

三宅 康博

実験課題名 Title of experiment

装置名 Name of Instrument/（BL No.）

Development of Silicon-strip detector for the muon g-2/EDM

D2 ミュオン基礎科学実験装置

experiment at J-PARC

実施日 Date of Experiment

実験責任者名 Name of principal investigator

2014/6/14-2014/6/15

三部 勉
所属 Affiliation
高エネルギー加速器研究機構 素粒子原子核研究所
試料、実験方法、利用の結果得られた主なデータ、考察、結論等を、記述して下さい。（適宜、図表添付のこと）
Please report your samples, experimental method and results, discussion and conclusions. Please add figures andtables for better explanation.
1. 試料 Name of sample(s) and chemical formula, or compositions including physical form.
Plastic scintillating plate

2. 実験方法及び結果 （実験がうまくいかなかった場合、その理由を記述してください。）
Experimental method and results.

If you failed to conduct experiment as planned, please describe reasons.

The experiment utilized the surface muon beam at the MUSE D2 port where surface muon beam isavailable at the intensity 6x106 /sec (300 kW proton beam power) with a 5% momentum bite. The
experimental setup is shown in Fig. 1. The surface muon beam at momentum 27.4 MeV/c was used.
After muon stops in the target scintillator, muon decay into a positron and two neutrinos. The detector
test equipment was placed at downstream of the beam line
consisting of four layers of silicon-strip sensors, two layersof plastic scintillating fiber hodoscopes, followed by a pairof time-defining plastic scintillators. The signal of silicon strip
sensor generated by decay e+ was measured by using acustum-made analog amplifer integrated circuit called SlitA.
Low noise level in the analog circuit line is critical in order tomake this detector working. After identifying proper
grounding scheme, the observed noise level was

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Figure 1: experim ental setup

2. 実験方法及び結果（つづき） Experimental method and results (continued)
about 5 mV(RMS) corresponding to ~1500 ENC as shown in Fig.2(left). This noise level was similar to what
was obtained in the offline test at a laboratory test bench.No significant issue was identified on noise
environment at MLF.
The instantaneous rate of the sensor was changed by moving sensors with respect to the muon stopping
target to check performance change under large amount of rate change. Data collection was successfullycompleted with anticipated statistics. Typical waveform of the analog output signal for the selected strip(27um width, 100um pitch) of the silicon-strip sensor is shown in Fig.2 (right). Following the data taking ofanalog waveform, threshold was set to about 50% of the minimum-ionization particles to test discriminator
function on SlitA readout chip. The output binary signal of the discriminator was recorded by TDC. Timespectrum of muon decay was reconstructed successfully. Detail analysis of pulse height and timing
response are under way to characterize the peformance of the sensor and readout electronics. Results ofthe analysis will be presented in Fall JPS meeting by S. Nishimura (U. Tokyo) and S. Shirabe (Kyushu-U).

Figure 2 : (left) distribution of analog signal when there is no beam indicating noise
distribution of the system , (right) typical distribution of the analog output of thereadout electronics (SlitA) connected to the silicon-strip sensor when a positron hitthe silicon-strip sensor

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