1204.6218 (D. Akimov et al.)

Light Yield in DarkSide-10: a Prototype Two-phase Liquid Argon TPC for
Dark Matter Searches    [PDF]

D. Akimov, T. Alexander, D. Alton, K. Arisaka, H. O. Back, P. Beltrame, J. Benziger, A. Bolozdynya, G. Bonfini, A. Brigatti, J. Brodsky, L. Cadonati, F. Calaprice, A. Candela, H. Cao, P. Cavalcante, A. Chavarria, A. Chepurnov, S. Chidzik, D. Cline, A. G. Cocco, C. Condon, D. D'Angelo, S. Davini, E. De Haas, A. Derbin, G. Di Pietro, I. Dratchnev, D. Durben, A. Empl, A. Etenko, A. Fan, G. Fiorillo, K. Fomenko, F. Gabriele, C. Galbiati, S. Gazzana, C. Ghag, C. Ghiano, A. Goretti, L. Grandi, M. Gromov, M. Guan, C. Guo, G. Guray, E. V. Hungerford, Al. Ianni, An. Ianni, A. Kayunov, K. Keeter, C. Kendziora, S. Kidner, V. Kobychev, G. Koh, D. Korablev, G. Korga, E. Shields, P. Li, B. Loer, P. Lombardi, C. Love, L. Ludhova, L. Lukyanchenko, A. Lund, K. Lung, Y. Ma, I. Machulin, J. Maricic, C. J. Martoff, Y. Meng, E. Meroni, P. D. Meyers, T. Mohayai, D. Montanari, M. Montuschi, P. Mosteiro, B. Mount, V. Muratova, A. Nelson, A. Nemtzow, N. Nurakhov, M. Orsini, F. Ortica, M. Pallavicini, E. Pantic, S. Parmeggiano, R. Parsells, N. Pelliccia, L. Perasso, F. Perfetto, L. Pinsky, A. Pocar, S. Pordes, G. Ranucci, A. Razeto, A. Romani, N. Rossi, P. Saggese, R. Saldanha, C. Salvo, W. Sands, M. Seigar, D. Semenov, M. Skorokhvatov, O. Smirnov, A. Sotnikov, S. Sukhotin, Y. Suvorov, R. Tartaglia, J. Tatarowicz, G. Testera, A. Teymourian, J. Thompson, E. Unzhakov, R. B. Vogelaar, H. Wang, S. Westerdale, M. Wojcik, A. Wright, J. Xu, C. Yang, S. Zavatarelli, M. Zehfus, W. Zhong, G. Zuzel

As part of the DarkSide program of direct dark matter searches using liquid argon TPCs, a prototype detector with an active volume containing 10 kg of liquid argon, DarkSide-10, was built and operated underground in the Gran Sasso National Laboratory in Italy. A critically important parameter for such devices is the scintillation light yield, as photon statistics limits the rejection of electron-recoil backgrounds by pulse shape discrimination. We have measured the light yield of DarkSide-10 using the readily-identifiable full-absorption peaks from gamma ray sources combined with single-photoelectron calibrations using low-occupancy laser pulses. For gamma lines of energies in the range 122-1275 keV, we get consistent light yields averaging 8.887\pm0.003(stat)\pm0.444(sys) p.e./keV_ee. With additional purification, the light yield measured at 511 keV increased to 9.142\pm0.006(stat) p.e./keV_ee.

View original: http://arxiv.org/abs/1204.6218