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تسجيل مستخدم جديدDevelopment of a low-alpha-emitting {mu}-PIC for NEWAGE direction-sensitive dark-matter search
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NEWAGE is a direction-sensitive dark-matter-search experiment that uses a micro-patterned gaseous detector, or {mu}-PIC, as the readout. The main background sources are {alpha}-rays from radioactive contaminants in the {mu}-PIC. We have therefore developed a low-alpha-emitting {mu}-PICs and measured its performances. We measured the surface {alpha}-ray emission rate of the {mu}-PIC in the Kamioka mine using a surface {alpha}-ray counter based on a micro TPC.
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Direction sensitivity could provide robust evidence for the direct detection of weakly interacting massive particles constituting dark matter. However, the sensitivity of this method remains low due to the radioactive backgrounds. The purpose of this
study is to develop a low-background detector as a two-dimensional imaging device for a gaseous time projection chamber. In direction-sensitive dark matter experiments~(e.g. NEWAGE), $alpha$-rays emitted from the detector components often create substantial radioactive backgrounds. Based on the study of the background of NEWAGE, a new detector low-$alpha$ $mu$-PIC is developed. The produced $mu$-PIC performs well as a gas detector and the $alpha$-ray emission rate from the $mu$-PIC reduced by a factor of 100.
NEWAGE is a direction-sensitive dark matter search using a low-pressure gaseous time projection chamber. A low alpha-ray emission rate micro pixel chamber had been developed in order to reduce background for dark matter search. We conducted the dark
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The known direction of motion of dark matter particles relative to the Earth may be a key for their unambiguous identification even in the presence of backgrounds. We describe a prototype detector that is able to reconstruct direction vectors of weak
ly interacting massive particles that may the dominant constituent of the dark matter in our galaxy. The detector uses a low-density gas (CF4) in a 10liter time-projection chamber with mesh-based electrodes and optical and charge readout. Initial results confirm good performance in the reconstruction of direction angle and sense (head-tail) for low-momentum nuclear recoils.
A direction-sensitive dark matter search experiment at Kamioka underground laboratory with the NEWAGE-0.3a detector was performed. The NEWAGE- 0.3a detector is a gaseous micro-time-projection chamber filled with CF4 gas at 152 Torr. The fiducial volu
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