TY - JOUR AU - NEXT Collaboration (Serra, L. et al AU - Sorel, M. AU - Alvarez, V. AU - Carcel, S. AU - Cervera-Villanueva, A. AU - Diaz, J. AU - Ferrario, P. AU - Gomez-Cadenas, J. J. AU - Laing, A. AU - Liubarsky, I. AU - Lopez-March, N. AU - Lorca, D. AU - Martin-Albo, J. AU - Martinez, A. AU - Monrabal, F. AU - Monserrate, M. AU - Muñoz Vidal, J. AU - Nebot-Guinot, M. AU - Querol, M. AU - Renner, J. AU - Rodriguez, J. AU - Simon, A. AU - Yahlali, N. PY - 2015 DA - 2015// TI - An improved measurement of electron-ion recombination in high-pressure xenon gas T2 - J. Instrum. JO - Journal of Instrumentation SP - P03025 - 21pp VL - 10 PB - Iop Publishing Ltd KW - Charge transport KW - multiplication and electroluminescence in rare gases and liquids KW - Double-beta decay detectors KW - Time projection chambers KW - Ionization and excitation processes AB - We report on results obtained with the NEXT-DEMO prototype of the NEXT-100 high-pressure xenon gas time projection chamber (TPC), filled with pure xenon gas at 10 bar pressure and exposed to an alpha decay calibration source. Compared to our previous measurements with alpha particles, an upgraded detector and improved analysis techniques have been used. We measure event-by-event correlated fluctuations between ionization and scintillation due to electronion recombination in the gas, with correlation coefficients between -0.80 and -0.56 depending on the drift field conditions. By combining the two signals, we obtain a 2.8% FWHM energy resolution for 5.49 MeV alpha particles and a measurement of the optical gain of the electroluminescent TPC. The improved energy resolution also allows us to measure the specific activity of the radon in the gas due to natural impurities. Finally, we measure the average ratio of excited to ionized atoms produced in the xenon gas by alpha particles to be 0.561 +/- 0.045, translating into an average energy to produce a primary scintillation photon of W-ex = (39.2 +/- 3.2) eV. SN - 1748-0221 UR - http://arxiv.org/abs/1412.3573 UR - https://doi.org/10.1088/1748-0221/10/03/P03025 DO - 10.1088/1748-0221/10/03/P03025 LA - English N1 - WOS:000357944500075 ID - NEXTCollaborationSerra_etal2015 ER -