Scintillation properties of N2 and CF4 and performances of a scintillating ionization chamber

Abstract

International audienceIn this work, we studied the emission yields, decay times and coincidence resolving times (CRT) of two gases, nitrogen (N2) and tetrafluoromethane (CF4), used for particle detection in the context of fission products measurement. The setup was made of an ionization chamber and two photomul-tiplier tubes (PMTs) placed front-to-front on each side of the active zone of the chamber. Using the photomultiplier tubes, the number of photoelectrons (phe) converted at the photocathodes from the scintillation processes in each gas were quantified and the scintillation time spectra were recorded. An scintillation emission yield of 24 phe MeV −1 with a decay time of τ d = 2.5 ns in N2, and 225 phe MeV −1 with τ d = 6.2 ns for CF4, have been measured. With our setup , the coincidence resolving time (σ values) between the two PMTs have been measured at 1.4 ns and 0.34 ns for N2 and CF4 respectively, using alpha particles

Qualification tests of the R11410-21 photomultiplier tubes for the XENON1T detector

“…The rates also depend on the shielding of the test setup and the distance between the opposing PMT structures. A larger distance between the PMT arrays increases the measured values and standard deviation of the DC rates, likely due to an increased solid angle to observe Cherenkov light or scintillation (390 nm wavelength photons [28]) in the N 2 gas from ionizing radiation such as cosmic rays and α particles. For the presented results the distance between two PMT windows is 2 cm.…”

The design of the n2EDM experiment

“…and the emitted proton and triton cause scintillation of the CF 4 molecules. The scintillation decay time is only about 10 ns [67], which provides a high count-rate capability up to a few 10 6 counts/s. The scintillation light is detected by three photomultiplier tubes working in coincidence.…”

A Review of Nanomaterial Based Scintillators

“…With the development of experimental physics and with the occurrence of the photoelectric multipliers, it became clear that scintillating materials are ideal devices to detect elementary particles and to measure their parameters [28,29]. In a fairly short time (1947~1951) it was discovered that scintillation can be observed in various organic and inorganic crystalline media [30][31][32][33], as well as in fluids [34][35][36][37], gases [38,39], and polymeric compounds [40]. At the same time, the most widely used scintillating crystalline material, NaI(Tl), was discovered [41].…”