The Electronics and Data Acquisition System for the DarkSide-50 Veto Detectors
P. Agnes, L. Agostino, I. F. M. Albuquerque, T. Alexander, A. K. Alton, K. Arisaka, H. O. Back, B. Baldin, K. Biery, G. Bonfini, M. Bossa, B. Bottino, A. Brigat… 展开作者
P. Agnes, L. Agostino, I. F. M. Albuquerque, T. Alexander, A. K. Alton, K. Arisaka, H. O. Back, B. Baldin, K. Biery, G. Bonfini, M. Bossa, B. Bottino, A. Brigatti, J. Brodsky, F. Budano, S. Bussino, M. Cadeddu, M. Cadoni, F. Calaprice, N. Canci, A. Candela, H. Cao, M. Cariello, M. Carlini, S. Catalanotti, P. Cavalcante, A. Chepurnov, A. G. Cocco, G. Covone, L. Crippa, D. D'Angelo, M. D'Incecco, S. Davini, S. De Cecco, M. De Deo, M. De Vincenzi, A. Derbin, A. Devoto, F. Di Eusanio, G. Di Pietro, E. Edkins, A. Empl, A. Fan, G. Fiorillo, K. Fomenko, G. Foster, D. Franco, F. Gabriele, C. Galbiati, C. Giganti, A. M. Goretti, F. Granato, L. Grandi, M. Gromov, M. Guan, Y. Guardincerri, B. R. Hackett, K. R. Herner, E. V. Hungerford, Aldo Ianni, Andrea Ianni, I. James, C. Jollet, K. Keeter, C. L. Kendziora, V. Kobychev, G. Koh, D. Korablev, G. Korga, A. Kubankin, X. Li, M. Lissia, P. Lombardi, S. Luitz, Y. Ma, I. N. Machulin, A. Mandarano, S. M. Mari, J. Maricic, L. Marini, C. J. Martoff, A. Meregaglia, P. D. Meyers, T. Miletic, R. Milincic, D. Montanari, A. Monte, M. Montuschi, M. E. Monzani, P. Mosteiro, B. J. Mount, V. N. Muratova, P. Musico, J. Napolitano, A. Nelson, S. Odrowski, M. Orsini, F. Ortica, L. Pagani, M. Pallavicini, E. Pantic, S. Parmeggiano, K. Pelczar, N. Pelliccia, A. Pocar, S. Pordes, D. A. Pugachev, H. Qian, K. Randle, G. Ranucci, A. Razeto, B. Reinhold, A. L. Renshaw, Q. Riffard, A. Romani, B. Rossi, N. Rossi, S. D. Rountree, D. Sablone, P. Saggese, R. Saldanha, W. Sands, S. Sangiorgio, C. Savarese, E. Segreto, D. A. Semenov, E. Shields, P. N. Singh, M. D. Skorokhvatov, O. Smirnov, A. Sotnikov, C. Stanford, Y. Suvorov, R. Tartaglia, J. Tatarowicz, G. Testera, A. Tonazzo, P. Trinchese, E. V. Unzhakov, A. Vishneva, R. B. Vogelaar, M. Wada, S. Walker, H. Wang, Y. Wang, A. W. Watson, S. Westerdale, J. Wilhelmi, M. M. Wojcik, X. Xiang, J. Xu, C. Yang, J. Yoo, S. Zavatarelli, A. Zec, W. Zhong, C. Zhu, G. Zuzel
DarkSide-50 is a detector for dark matter candidates in the form of weakly interacting massive particles (WIMPs). It utilizes a liquid argon time projection chamber (LAr TPC) for the inner main detector. The TPC is surrounded by a liquid scintillator veto (LSV) and a water Cherenkov veto detector (WCV). The LSV and WCV, both instrumented with PMTs, act as the neutron and cosmogenic muon veto detectors for DarkSide-50. This paper describes the electronics and data acquisition system used for these two detectors.
DarkSide-20k is a rare-event search experiment aimed at finding signals of dark matter particles. It is a dual-phase detector that registers ionisation and scintillation signals originating from the particles interacting with the liquid argon detector medium. It is enclosed in a single-phase liquid argon neutron veto tank, equipped with Gd-loaded panels for capturing neutrons. Since vetoing and particle identification are carried out using the light signal, it is crucial to maximise the light yield. Light collection efficiency depends on optical properties of the detector and particularly for …
DarkSide is a staged experimental project based on radiopure argon aiming at direct dark matter detection. The DarkSide-50 (DS-50) detector is currently operating underground at the Gran Sasso National Laboratory. DS-50 detector is a dual-phase, 50 kg, liquid argon time-projection-chamber readout by 38 cryogenic PMTs (Hamamatsu R11065), surrounded by an active liquid scintillator veto and contained in a water Cherenkov detector acting as a muon veto. DS-50 has been been operating continuously since 2013, first with atmospheric argon and subsequently filled in 2015 with argon from an undergroun…
Nuclear recoil events produced by neutron scatters form one of the most important classes of background in WIMP direct detection experiments, as they may produce nuclear recoils that look exactly like WIMP interactions. In DarkSide-50, we both actively suppress and measure the rate of neutron-induced background events using our neutron veto, composed of a boron-loaded liquid scintillator detector within a water Cherenkov detector. This paper is devoted to the description of the neutron veto system of DarkSide-50, including the detector structure, the fundamentals of event reconstruction and da…
DarkSide-50 is the first physics detector of the DarkSide dark matter search program. The detector features a dual-phase underground-argon Time Projection Chamber (TPC) of 50 kg active mass surrounded by an organic liquid-scintillator neutron veto (30 tons) and a water-Cherenkov muon detector (1000 tons). The TPC is currently fully shielded and operating underground at Gran Sasso National Laboratory. A first run of 1422 kg-day exposure with atmospheric argon represents the most sensitive dark matter search using a liquid argon target. The TPC is now filled with underground argon, greatly reduc…
In the published cosmogenic background study for a ton-sized DarkSide dark matter search, only prompt neutron backgrounds coincident with cosmogenic muons or muon induced showers were considered, although observation of the initiating particle(s) was not required. The present paper now reports an initial investigation of the magnitude of cosmogenic background from $β$-delayed neutron emission produced by cosmogenic activity in DarkSide. The study finds a background rate for $β$-delayed neutrons in the fiducial volume of the detector on the order of < 0.1 event/year. However, detailed studies a…
Building on the successful experience in operating the DarkSide-50 detector, the DarkSide Collaboration is going to construct DarkSide-20k, a direct WIMP search detector using a two-phase Liquid Argon Time Projection Chamber (LArTPC) with an active (fiducial) mass of 23 t (20 t). The DarkSide-20k LArTPC will be deployed within a shield/veto with a spherical Liquid Scintillator Veto (LSV) inside a cylindrical Water Cherenkov Veto (WCV). Operation of DarkSide-50 demonstrated a major reduction in the dominant $^{39}$Ar background when using argon extracted from an underground source, before apply…
The DarkSide-50 experiment at the Laboratori Nazionali del Gran Sasso is a search for dark matter using a dual phase time projection chamber with 50 kg of low radioactivity argon as target. Light signals from interactions in the argon are detected by a system of 38 photo-multiplier tubes (PMTs), 19 above and 19 below the TPC volume inside the argon cryostat. We describe the electronics which processes the signals from the photo-multipliers, the trigger system which identifies events of interest, and the data-acquisition system which records the data for further analysis. The electronics includ…
This paper describes the design, fabrication, commissioning and use of a CALibration source Insertion System (CALIS) in the DarkSide-50 direct dark matter search experiment. CALIS deploys radioactive sources into the liquid scintillator veto to characterize the detector response and detection efficiency of the DarkSide-50 Liquid Argon Time Projection Chamber, and the surrounding 30 t organic liquid scintillator neutron veto. It was commissioned in September 2014 and has been used successfully in several gamma and neutron source campaigns since then. A description of the hardware and an excerpt…
It is generally inferred from astronomical measurements that Dark Matter (DM) comprises approximately 27\% of the energy-density of the universe. If DM is a subatomic particle, a possible candidate is a Weakly Interacting Massive Particle (WIMP), and the DarkSide-50 (DS) experiment is a direct search for evidence of WIMP-nuclear collisions. DS is located underground at the Laboratori Nazionali del Gran Sasso (LNGS) in Italy, and consists of three active, embedded components; an outer water veto (CTF), a liquid scintillator veto (LSV), and a liquid argon (LAr) time projection chamber (TPC). Thi…
We report the first results of DarkSide-50, a direct search for dark matter operating in the underground Laboratori Nazionali del Gran Sasso (LNGS) and searching for the rare nuclear recoils possibly induced by weakly interacting massive particles (WIMPs). The dark matter detector is a Liquid Argon Time Projection Chamber with a (46.4+-0.7) kg active mass, operated inside a 30 t organic liquid scintillator neutron veto, which is in turn installed at the center of a 1 kt water Cherenkov veto for the residual flux of cosmic rays. We report here the null results of a dark matter search for a (142…
This paper describes the design of the active muon veto subsystem for the MiniCLEAN dark matter direct detection experiment at SNOLAB in Sudbury, Ontario, Canada. The water-filled veto is instrumented with 48 PMTs which are read out by front end electronics to time multiplex 48 photomultiplier channels into 6 digitizer channels and provide an instantaneous hit sum across the subsystem (N-Hit) for the veto trigger. We describe the primary system components: the PMTs, the support structure, the front-end electronics, and the data acquisition system.
COSINE-100 is a dark matter direct detection experiment designed to test the annual modulation signal observed by the DAMA/LIBRA experiment. COSINE-100 consists of 8 NaI(Tl) crystals with a total mass of 106 kg, a 2200 L liquid scintillator veto, and 37 muon detector panels. We present details of the data acquisition system of COSINE-100, including waveform storage using flash analog-to-digital converters for crystal events and integrated charge storage using charge-sensitive analog-to-digital converters for liquid scintillator and plastic scintillator muon veto events. We also discuss several…
The JSNS$^{2}$ (J-PARC Sterile Neutrino Search at J-PARC Spallation Neutron Source) experiment aims to search for neutrino oscillations over a 24 m short baseline at J-PARC. The JSNS$^{2}$ inner detector is filled with 17 tons of gadolinium(Gd)-loaded liquid scintillator (LS) with an additional 31 tons of unloaded LS in the intermediate $γ$-catcher and an optically separated outer veto volumes. A total of 120 10-inch photomultiplier tubes observe the scintillating optical photons and each analog waveform is stored with the flash analog-to-digital converters. We present details of the data acqu…
One of the most powerful techniques for direct detection of dark matter via elastic scattering of galactic WIMPs is the use of liquid argon time projection chambers. Atmospheric argon (AAr) has a naturally occurring radioactive isotope, \ar{}, of cosmogenic origin. The use of argon extracted from underground wells, deprived of \ar{}, is key to the physics potential of these experiments. The DarkSide-20k (DS-20k) dark matter search experiment will operate with 50 tonnes of radio-pure underground argon (UAr), extracted from the Urania plant in Cortez (USA) and purified in the Aria distillation p…
The Neutrinos Angra Experiment has completed a major step by finishing the comissioning of the detector and the data acquisition system at the experimental site located in the Angra dos Reis nuclear power plant. The experiment consists of a water-based detector and associated electronics, both designed with the goal of detecting the electron antineutrinos produced by the nuclear reactor. The detection is possible due to the Inverse Beta Decay, where the final products in the water are photons in the UV-to-visible range of the spectrum. The assembled detector comprises three active volumes fill…
Large liquid argon detectors offer one of the best avenues for the detection of galactic weakly interacting massive particles (WIMPs) via their scattering on atomic nuclei. The liquid argon target allows exquisite discrimination between nuclear and electron recoil signals via pulse-shape discrimination of the scintillation signals. Atmospheric argon (AAr), however, has a naturally occurring radioactive isotope, $^{39}$Ar, a $β$ emitter of cosmogenic origin. For large detectors, the atmospheric $^{39}$Ar activity poses pile-up concerns. The use of argon extracted from underground wells, deprive…
This article describes the setup and performance of the near and far detectors in the Double Chooz experiment. The electron antineutrinos of the Chooz nuclear power plant were measured in two identically designed detectors with different average baselines of about 400 m and 1050 m from the two reactor cores. Over many years of data taking the neutrino signals were extracted from interactions in the detectors with the goal of measuring a fundamental parameter in the context of neutrino oscillation, the mixing angle θ13. The central part of the Double Chooz detectors was a main detector comprisi…
The Jiangmen Underground Neutrino Observatory (JUNO) is proposed to determine the neutrino mass hierarchy using an underground liquid scintillator detector. It is located 53 km away from both Yangjiang and Taishan Nuclear Power Plants in Guangdong, China. The experimental hall, spanning more than 50 meters, is under a granite mountain of over 700 m overburden. Within six years of running, the detection of reactor antineutrinos can resolve the neutrino mass hierarchy at a confidence level of 3-4$σ$, and determine neutrino oscillation parameters $\sin^2θ_{12}$, $Δm^2_{21}$, and $|Δm^2_{ee}|$ to …
