DarkSide-50 is a dual-phase argon Time Projection Chamber (TPC), developed for use in a search for direct evidence of dark matter. The experiment is housed in Hall C of the Laboratori Nazionali del Gran Sasso, underneath the Gran Sasso e Monti della Laga National Park, and has been online since October 2013.
Description of the detector and related techniques
DarkSide-50 is a dual-phase argon TPC. Thirty-eight 3" Hamamatsu low-background R11065 PMTs (photomultiplier tubes), 19 each on the top and the bottom, view the active region through fused silica windows. The windows are coated on both sides with Indium Tin Oxide, ITO, a transparent conductor. This allows the inner window surfaces to serve as the grounded anode (top) and -60 KV cathode (bottom) of the TPC while maintaining their outer surfaces near the -1.5 KV PMT photocathode potential.
A gas layer for production of the electrolumnescence signature is provided by a cylindrical rim on the fused silica anode window, which extends downward to form a “diving bell” containing the 2cm-thick argon vapor layer (“gas pocket”) above the TPC drift volume. The cylindrical vessel containing the active region is made of PTFE, treated to be highly reflective at visible wavelengths. The entire inner surface of the active volume is coated with the wavelength shifter TetraPhenylButadiene (TPB) to convert the 128nm argon scintillation into the wavelength range detectable by the PMTs. The drift field is produced by system consisting of the ITO cathode and anode planes, a field cage, and a grid that separates the drift and electron extraction regions.
The DarkSide-50 TPC is deployed within a borated liquid scintillator-based neutron veto (LSV), which is in turn inside a water Cherenkov muon veto. This not only gives DarkSide-50 the benefits of active background suppression, but also gives us direct experience in operating a low background experiment in these active shields, in preparation for future upgrades.
JLIB_HTML_CLOAKING (Princeton University)
JLIB_HTML_CLOAKING (INFN Milano)
Institute of High Energy Physics, Beijing: M. Y. Guan, P. X. Li, Y. Q. Ma, Y. Wang, C. G. Yang
APC, Université Paris Diderot, Sorbonne Paris Cité: P. Agnes, D. Franco, S. Perasso, A. Tonazzo
LPNHE, Université Pierre et Marie Curie, Université Paris Diderot, CNRS/IN2P3: L. Agostino, S. De Cecco, C. Giganti
IPHC, Université de Strasbourg, CNRS/IN2P3: C. Jollet, A. Meregaglia
Università degli Studi and INFN Cagliari: M. Cadoni, A. Devoto, M. Lissia
Università degli Studi and INFN Genova: M. Cariello, P. Musico, L. Pagani, M. Pallavicini, L. Perasso, G. Testera, S. Zavatarelli
Gran Sasso Science Institute: M. Bossa, J. P. Fontaine, A. Mandarano, C. Savarese
INFN Laboratori Nazionali del Gran Sasso: G. Bonfini, A. Candela, P. Cavalcante, M. D’Incecco, M. De Deo, F. Gabriele, Al. Ianni, M. Montuschi, S. Odrowski, M. Orsini, A. Razeto, N. Rossi, D. Sablone, E. Segreto, R. Tartaglia
Università degli Studi and INFN Milano: A. Brigatti, D. D’Angelo, G. Di Pietro, P. Lombardi, L. Ludhova, E. Meroni, S. Parmeggiano, G. Ranucci, P. Saggese
Università degli Studi Federico II and INFN Napoli: Catalanotti, A. G. Cocco, G. Covone, G. Fiorillo, B. Rossi, S. Walker
Università degli Studi and INFN Perugia: F. Ortica, N. Pelliccia, A. Romani
Università degli Studi Roma Tre and INFN: F. Budano, S. Bussino, M. De Vincenzi, I. James, S. Mari, L. Marini
Università di Roma “La Sapienza” and INFN: C. Dionisi, S. Giagu, M. Rescigno
Joint Institute for Nuclear Research Dubna: K. Fomenko, D. Korablev, O. Smirnov, A. Sotnikov, A. Vishneva
National Research Centre Kurchatov Institute: G. Lukyachenko, I. Machulin, D. Markov, D. Pugachev, M. Skorokhvatov
Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University, Moscow: A. Chepurnov, M. Gromov
St. Petersburg Nuclear Physics Institute: A. Derbin, V. Muratova, D. Semenov, E. Unzhakov
Institute for Nuclear Research, National Academy of Sciences of Ukraine: V. Kobychev
Smoluchowski Institute of Physics, Jagiellonian University, Krakow: A. Odrzywolek, K. Pelczar, M. Wojcik, G. Zuzel
PNNL (Pacific Northwest National Laboratory): C. Aalseth, D. Asner, M. Foxe, A. Hime, P. Humble, J. Orrell, R. Williams
Physics and Astronomy Department, Augustana College: A. Alton, M. Smallcomb
Kavli Institute, Enrico Fermi Institute and Dept. of Physics, University of Chicago: A. Chavarria, L. Grandi, R. Saldanha, T. Wester
School of Natural Sciences, Black Hills State University, Spearfish: D. Durbin, K. Keeter, B. Mount, V. Price, M. Zephus
Fermi National Accelerator Laboratory: B. Baldin, K. Biery, Y. Guardincerri, K. Herner, C. Kendziora, D. Montanari, S. Pordes, J. Yoo
Department of Physics and Astronomy, University of Hawai’i: E. Edkins, B. Hackett, J. Maricic, R. Milincic, B. Reinhold
Department of Physics, University of Houston: S. Davini, A. Empl, E. V. Hungerford, G. Korga, D. Sablone
Lawrence Livermore National Laboratory: S. Sangiorgio
Department of Physics, Princeton University: H. O. Back, J. Brodsky, F. Calaprice, H. Cao, C. Condon, F. Di Eusanio, C. Galbiati, A. Goretti, An. Ianni, R. Klemmer, G. Koh, M. Komor, B. Loer, P. D. Meyers, P. Mosteiro, A. Nelson, R. Parsells, H. Qian, B. Rossi, W. Sands, E. Shields, M. Souza, C. Stanford, M. Wada, S. Westerdale, A. Wright, X. Xiang, J. Xu, C. Zhu
SLAC National Accelerator Laboratory: G. Haller, R. Herbst, S. Luitz, M. E. Monzani
Physics Department, Temple University: C. Love, C. J. Martoff, T. Miletic, K. Recine, J. Tatarowicz, A. Watson
Department of Chemistry and Physics, Arcadia University: T. Miletic
Physics Department, University of California: E. Pantic
Physics and Astronomy Department, University of California: K. Arisaka, N. Canci, A. Fan, E. Pantic, A. Renshaw, Y. Suvorov, H. Wang
Amherst Center for Fundamental Interactions and Physics Department: T. Alexander, J. Bonatt, L. Cadonati, G. Forster, A. Kurlej, A. Monte, A. Nemtzow, A. Pocar, K. Randle, A. Zec
Physics Department, Virginia Tech: S. Kidner [deceased], L. Papp, S. D. Rountree, R. B. Vogelaar
An updated list of the Collaboration can be found here: http://darkside.lngs.infn.it/collaboration/
P. Agnes et al. “First results from the DarkSide-50dark matter experiment at Laboratori Nazionali del Gran Sasso”. Physics Letters B, 743 (2015): 456-466.
C. E. Aalseth et al. “The DarkSide Multiton Detector for the Direct Dark Matter Search”. Advances in High Energy Physics, 2015 (2015): 541362.
J. Xu et al. “A study of the trace 39Ar content in argon from deep underground sources”. Astroparticle Physics, 66 (2015): 53-60.