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تسجيل مستخدم جديدTransport properties of electrons in CF4
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Carbon-tetrafluoride (CF4) is used as a counting gas in particle detectors, but some of its properties that are of interest for large time-projection chambers are not well known. We measure the mean energy, which is proportional to the diffusion coefficent, and the attentuation coefficient of electron propagation in CF4 gas using a 10-liter dark matter detector prototype of the DMTPC project.
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This paper presents a measurement of the ratio of photon to electron production and the scintillation spectrum in a popular gas for time pro jection chambers, carbon tetrafluoride (CF4), over the range of 200 to 800 nm; the ratio is measured to be 0.
34+/-0.04. This result is of particular importance for a new generation of dark matter time projection chambers with directional sensitivity which use CF4 as a fill gas.
Argon with an admixture of CF4 is expected to be a good candidate for the gas mixture to be used for a time projection chamber (TPC) in the future linear collider experiment because of its small transverse diffusion of drift electrons especially unde
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