PT Journal
AU NEXT Collaboration (Fernandes, AFMea
   Alvarez, V
   Benlloch-Rodriguez, JM
   Carcel, S
   Carrion, JV
   Diaz, J
   Felkai, R
   Herrero, P
   Kekic, M
   Lopez-March, N
   Martinez-Lema, G
   Muñoz Vidal, J
   Novella, P
   Palmeiro, B
   Querol, M
   Renner, J
   Romo-Luque, C
   Sorel, M
   Uson, A
   Yahlali, N
TI Low-diffusion Xe-He gas mixtures for rare-event detection: electroluminescence yield
SO Journal of High Energy Physics
JI J. High Energy Phys.
PY 2020
BP 034
EP 18pp
VL 04
IS 4
DI 10.1007/JHEP04(2020)034
LA English
DE Particle correlations and fluctuations; Photon production; Dark Matter and Double Beta Decay (experiments); Rare decay
AB High pressure xenon Time Projection Chambers (TPC) based on secondary scintillation (electroluminescence) signal amplification are being proposed for rare event detection such as directional dark matter, double electron capture and double beta decay detection. The discrimination of the rare event through the topological signature of primary ionisation trails is a major asset for this type of TPC when compared to single liquid or double-phase TPCs, limited mainly by the high electron diffusion in pure xenon. Helium admixtures with xenon can be an attractive solution to reduce the electron diffu- sion significantly, improving the discrimination efficiency of these optical TPCs. We have measured the electroluminescence (EL) yield of Xe-He mixtures, in the range of 0 to 30% He and demonstrated the small impact on the EL yield of the addition of helium to pure xenon. For a typical reduced electric field of 2.5 kV/cm/bar in the EL region, the EL yield is lowered by similar to 2%, 3%, 6% and 10% for 10%, 15%, 20% and 30% of helium concentration, respectively. This decrease is less than what has been obtained from the most recent simulation framework in the literature. The impact of the addition of helium on EL statistical fluctuations is negligible, within the experimental uncertainties. The present results are an important benchmark for the simulation tools to be applied to future optical TPCs based on Xe-He mixtures.
ER