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The Time Projection Chamber (TPC) has been recognized as a doubtlessly highly effective detector for the search of WIMPs by measuring the instructions of nuclear recoils, in which the most convincing signature of WIMPs, attributable to the Earth’s movement around the Galaxy, appears. We report on the primary outcomes of a efficiency examine of the neutron exposure of our prototype micro TPC with Ar-C2H6 (90:10) and CF4 gasoline at a hundred and fifty Torr. These particles could be detected directly by measuring the nuclear recoils produced by their elastic scattering off nuclei in detectors. The most convincing signature of WIMPs seems within the directions of nuclear recoils. Since the energy deposits of WIMPs to nuclei are only a few tens of keV and iTagPro shop the vary of nuclei is proscribed, the micro-TPC should be operated at low pressures. In the present work, as a way to look at the response of the micro-TPC to nuclear recoils at low pressures as a first step, we irradiated a a hundred and fifty Torr Ar-C2H6 (90:10 mixture) fuel (one among the usual gases for TPCs) and best bluetooth tracker CF4 with neutrons from 252Cf. The track lengths and deposited energies of Ar, C, and F recoils were investigated.

The prototype micro-TPC used on this measurements is shown in Fig.1. PIC and everyday tracker tool GEM. The small print of this GEM are described in Refs. The pre-amplified indicators are summed and digitized by one hundred MHz 8bit flash ADCs in order to determine the deposited vitality and everyday tracker tool the track route as the waveforms hold the Bragg curve shapes. Ar-C2H6 (90:10) or CF4 gasoline to a stress of one hundred fifty Torr and sealed all through the measurement. For travel security tracker measuring the fuel acquire and the energy calibration, the gasoline was irradiated with 109Cd 22 keV and 133Ba 31.Zero keV X-rays by a 1mm thick aluminum window close to the sensitive quantity. We irradiated the micro-TPC with neutrons from a 1 MBq 252Cf supply on the highest of the vessel. 2 cm3 plastic scintillator have been used as the event set off. PIC and GEM with a rather low gasoline gain (under 1000) in order to observe the nuclear recoils.

PIC and changed the voltage between the GEM electrodes. Below a gasoline achieve of about 2000, our system was not capable of measure the 109Cd 22 keV x-ray correctly as a result of a mismatch of the dynamic range of the ASD chips and the flash ADC; therefore, the deposited energy in low-gain operations was extrapolated from the calibrations with the high gasoline gain operations. We evaluated the observe length as a operate of the measured electron equal power in the following manner. E/dx