Development of Gaseous Tracking Devices for the Search Of WIMPs > 자유게시판

The Time Projection Chamber (TPC) has been recognized as a probably powerful detector for the search of WIMPs by measuring the instructions of nuclear recoils, by which essentially the most convincing signature of WIMPs, caused by the Earth’s motion across the Galaxy, seems. We report on the first results of a performance research of the neutron publicity of our prototype micro TPC with Ar-C2H6 (90:10) and CF4 gasoline at 150 Torr. These particles may very well be detected immediately by measuring the nuclear recoils produced by their elastic scattering off nuclei in detectors. Essentially the most convincing signature of WIMPs appears in the directions of nuclear recoils. Since the power deposits of WIMPs to nuclei are just a few tens of keV and the vary of nuclei is proscribed, iTagPro geofencing the micro-TPC should be operated at low pressures. In the current work, iTagPro bluetooth tracker as a way to study the response of the micro-TPC to nuclear recoils at low pressures as a first step, we irradiated a one hundred fifty Torr Ar-C2H6 (90:10 mixture) gas (one in all the usual gases for iTagPro bluetooth tracker TPCs) and CF4 with neutrons from 252Cf. The monitor lengths and iTagPro bluetooth tracker deposited energies of Ar, C, and F recoils were investigated.

The prototype micro-TPC used in this measurements is proven in Fig.1. PIC and GEM. The details of this GEM are described in Refs. The pre-amplified indicators are summed and iTagPro bluetooth tracker digitized by 100 MHz 8bit flash ADCs so as to determine the deposited vitality and the track route because the waveforms hold the Bragg curve shapes. Ar-C2H6 (90:10) or CF4 gasoline to a strain of 150 Torr and sealed all through the measurement. For measuring the gas achieve and the energy calibration, the fuel was irradiated with 109Cd 22 keV and 133Ba 31.0 keV X-rays by a 1mm thick aluminum window close to the delicate volume. We irradiated the micro-TPC with neutrons from a 1 MBq 252Cf supply on the highest of the vessel. 2 cm3 plastic scintillator had been used as the event set off. PIC and GEM with a relatively low fuel gain (beneath 1000) with the intention to observe the nuclear recoils.

PIC and altered the voltage between the GEM electrodes. Below a fuel achieve of about 2000, our system was not able to measure the 109Cd 22 keV x-ray accurately due to a mismatch of the dynamic vary of the ASD chips and the flash ADC; subsequently, the deposited power in low-achieve operations was extrapolated from the calibrations with the excessive gas gain operations. We evaluated the observe length as a perform of the measured electron equal power in the following method. E/dx