Electroluminescence pulse shape and electron diffusion in liquid argon measured in a dual-phase TPC
P. Agnes, I. F. M. Albuquerque, T. Alexander, A. K. Alton, D. M. Asner, M. P. Ave, H. O. Back, B. Baldin, G. Batignani, K. Biery, V. Bocci, G. Bonfini, W. Boniv… 展开作者
P. Agnes, I. F. M. Albuquerque, T. Alexander, A. K. Alton, D. M. Asner, M. P. Ave, H. O. Back, B. Baldin, G. Batignani, K. Biery, V. Bocci, G. Bonfini, W. Bonivento, M. Bossa, B. Bottino, F. Budano, S. Bussino, M. Cadeddu, M. Cadoni, F. Calaprice, A. Caminata, N. Canci, A. Candela, M. Caravati, M. Cariello, M. Carlini, M. Carpinelli, S. Catalanotti, V. Cataudella, P. Cavalcante, S. Cavuoti, A. Chepurnov, C. Cicalo, A. G. Cocco, G. Covone, D. D'Angelo, M. D'Incecco, D. D'Urso, S. Davini, A. De Candia, S. De Cecco, M. De Deo, G. De Filippis, G. De Rosa, M. De Vincenzi, P. Demontis, A. V. Derbin, A. Devoto, F. Di Eusanio, G. Di Pietro, C. Dionisi, E. Edkins, A. Fan, G. Fiorillo, K. Fomenko, D. Franco, F. Gabriele, A. Gabrieli, C. Galbiati, S. Giagu, C. Giganti, G. K. Giovanetti, A. M. Goretti, F. Granato, M. Gromov, M. Guan, Y. Guardinbcerri, M. Gulino, B. R. Hackett, K. Herner, D. Hughes, P. Humble, E. V. Hungerford, An. Ianni, I. James, T. N. Johnson, K. Keeter, C. L. Kendziora, G. Koh, D. Korablev, G. Korga, A. Kubankin, M. Kuss, X. Li, M. Lissia, B. Loer, G. Longo, Y. Ma, A. A. Machado, I. N. Machulin, A. Mandarano, S. M. Mari, J. Maricic, C. J. Martoff, A. Messina, P. D. Meyers, R. Milincic, A. Monte, M. Morrocchi, B. J. Mount, V. N. Muratova, P. Musico, A. Navrer Agasson, A. Nozdrina, A. Oleinik, M. Orsini, F. Ortica, L. Pagani, M. Pallavicini, L. Pandola, E. Pantic, E. Paoloni, F. Pazzona, K. Pelczar, N. Pelliccia, A. Pocar, S. Pordes, H. Qian, M. Razeti, A. Razeto, B. Reinhold, A. L. Renshaw, M. Rescigno, Q. Riffard, A. Romani, B. Rossi, N. Rossi, D. Sablone, O. Samoylov, W. Sands, S. Sanfilippo, M. Sant, C. Savarese, B. Schlitzer, E. Segreto, D. A. Semenov, A. Sheshukov, P. N. Singh, M. D. Skorokhvatov, O. Smirnov, A. Sotnikov, C. Stanford, G. B. Suffritti, Y. Suvorov, R. Tartaglia, G. Testera, A. Tonazzo, P. Trinchese, E. V. Unzhakov, M. Verducci, A. Vishneva, B. Vogelaar, M. Wada, T. J. Waldrop, S. Walker, H. Wang, Y. Wang, A. W. Watson, S. Westerdale, M. M. Wojcik, X. Xiang, X. Xiao, C. Yang, Z. Ye, C. Zhu, G. Zuzel
We report the measurement of the longitudinal diffusion constant in liquid argon with the DarkSide-50 dual-phase time projection chamber. The measurement is performed at drift electric fields of 100 V/cm, 150 V/cm, and 200 V/cm using high statistics $^{39}$Ar decays from atmospheric argon. We derive an expression to describe the pulse shape of the electroluminescence signal (S2) in dual-phase TPCs. The derived S2 pulse shape is fit to events from the uppermost portion of the TPC in order to characterize the radial dependence of the signal. The results are provided as inputs to the measurement of the longitudinal diffusion constant DL, which we find to be (4.12 $\pm$ 0.04) cm$^2$/s for a selection of 140keV electron recoil events in 200V/cm drift field and 2.8kV/cm extraction field. To study the systematics of our measurement we examine datasets of varying event energy, field strength, and detector volume yielding a weighted average value for the diffusion constant of (4.09 $\pm$ 0.09) cm$^2$ /s. The measured longitudinal diffusion constant is observed to have an energy dependence, and within the studied energy range the result is systematically lower than other results in the literature.
AXEL is a high pressure xenon gas TPC detector being developed for neutrinoless double-beta decay search. We use the proportional scintillation mode with a new electroluminescence light detection system to achieve high energy resolution in a large detector. The detector also has tracking capabilities, which enable significant background rejection. To demonstrate our detection technique, we constructed a 10L prototype detector filled with up to 10bar xenon gas. The FWHM energy resolution obtained by the prototype detector is 4.0 $\pm$ 0.30 $\%$ at 122 keV, which corresponds to 0.9 ~ 2.0 % when …
Gas Electroluminescence in a Dual Phase Xenon-Doped Argon Detector
Lawrence Livermore National Laboratory（劳伦斯利弗莫尔国家实验室）；University of California Davis（加州大学戴维斯分校）；University of California San Diego（加州大学圣地亚哥分校）；University of California Riverside（加州大学河滨分校）
The dual-phase xenon time projection chamber (TPC) is a leading detector technology in rare event searches for dark matter and neutrino physics. The success of this type of detector technology relies on its capability to detect both primary scintillation and ionization signals from particle interactions in liquid xenon (LXe). The ionization electrons are converted into electroluminescence in the gas xenon (GXe), where a single electron can be amplified by more than 100 times in number of photons in a strong electric field. Maintaining a strong and uniform electric field in the small gas gap in…
We further study the effect of neutral bremsstrahlung (NBrS) in two-phase argon electroluminescence (EL), revealed recently in [1]. The absolute EL yield due to NBrS effect, in the visible and NIR range, was remeasured in pure gaseous argon in the two-phase mode, using a two-phase detector with EL gap read out directly by cryogenic PMTs and SiPMs. Possible applications of the NBrS effect in detection science are discussed, including those in two-phase dark matter detectors.
The Short Baseline Near Detector (SBND) is a 112 ton active mass liquid argon time projection chamber (LArTPC) that will begin operations in the Booster Neutrino Beamline at Fermilab in 2020. Its main physics goals include high-statistics measurements of neutrino-argon interaction cross-sections and searches for sterile neutrino oscillations as part of three LArTPCs that make up the Short Baseline Neutrino (SBN) Program at Fermilab. In addition, SBND serves as an R\&D platform for future LArTPC detectors such as those employed by the Deep Underground Neutrino Experiment (DUNE). One of the tech…
The DUNE Near Detector design consists of multiple components, each designed to produce complementary constraints on flux and neutrino interaction systematic uncertainties for the oscillation analyses. One of these subdetectors is a magnetized high-pressure gaseous-argon TPC (HPgTPC), which will provide fine-grained tracking in a low-density detector, using the same target nucleus as the DUNE far detector. With its low momentum threshold for particle detection, the HPgTPC will be able to constrain one of the most crucial - and least-well understood - uncertainties for the oscillation analysis:…
The study of proportional electroluminescence in two-phase argon is relevant in the field of noble-gas liquid detectors for dark matter search and low-energy neutrino experiments. In this work, we continued to study proportional electroluminescence (EL) in two-phase argon doped with a minor (9 ppm) admixture of nitrogen, in the VUV, UV and visible spectral ranges. We confirmed the effect of enhancement of the EL yield, as well as the presence of non-VUV component in addition to that of VUV, in proportional electroluminescence in two-phase Ar. On the other hand, the contribution of non-VUV comp…
The use of xenon-doped liquid argon is a promising alternative for large pure liquid-argon TPCs. Not only xenon-doped liquid argon enhances the light production, mitigating the possible suppression due to impurities, but also it increases the wavelength of the scintillation light, enlarging the effective Rayleigh scattering length and improving the detection uniformity. ProtoDUNE Dual-Phase is a 300-ton active volume LAr TPC, a prototype for the Deep Underground Neutrino Experiment (DUNE), a dual-site experiment for long-baseline neutrino oscillation studies, neutrino astrophysics and nucleon …
The ICARUS T600, a liquid argon time projection chamber (LAr-TPC) detector mainly devoted to neutrino physics, underwent a major overhauling at CERN in 2016-2017, which included also a new design of the read-out electronics, in view of its operation in Fermilab on the Short Baseline Neutrino (SBN) beam from 2019. The new more compact electronics showed capability of handling more efficiently the signals also in the intermediate Induction 2 wire plane with a significant increase of signal to noise (S/N), allowing for charge measurement also in this view. The new front-end and the analog to digi…
DarkSide-20k (DS-20k) will exploit the physical and chemical properties of liquid argon housed within a large dual-phase time project chamber (TPC) in its direct search for dark matter. The TPC will utilize a compact, integrated design with many novel features to enable the \SI{20}{t} fiducial volume of underground argon. Underground Argon (UAr) is sourced from underground CO$_2$ wells and depleted in the radioactive isotope $^{39}$Ar, greatly enhancing the experimental sensitivity to dark matter interactions. Sourcing and transporting the $\mathcal{O}$(\SI{100}{t}) of UAr for DS-20k is costly…
We demonstrate, for the time, the operation of a bubble-assisted Liquid Hole Multiplier (LHM) in liquid argon. The LHM, sensitive to both radiation-induced ionization electrons and primary scintillation photons, consists of a perforated electrode immersed in the noble liquid, with a stable gas-bubble trapped underneath. Electrons deposited in the liquid or scintillation-induced photoelectrons emitted from a photocathode on the electrode's surface, are collected into the holes; after crossing the liquid-gas interface, they induce electroluminescence within the bubble. After having validated in …
A double-phase Ar detector can efficiently identify particles and reconstruct their positions. However, the properties of electroluminescence (EL) for secondary light emission in the gas phase are not fully understood. Earlier studies have explained the EL process using an ordinary EL mechanism because of an Ar excimer; however, this mechanism does not predict the emission of visible light (VL). Recent measurements have demonstrated VL components in Ar gas EL, to explain which a new mechanism called neutral bremsstrahlung (NBrS) was proposed. In this study, we investigated gaseous Ar EL in the…
Proportional electroluminescence (EL) in noble gases is used in two-phase detectors for dark matter search to record ionization signals in the gas phase induced by particle scattering in the liquid phase (S2 signals). In this work, the EL pulse-shapes in a two-phase argon detector have for the first time been studied systematically in a wide range of reduced electric field, varying from 3 to 9 Td. The pulse-shapes were studied at different readout configurations and spectral ranges: using cryogenic PMTs and SiPMs, with and without a wavelength shifter (WLS), in the VUV and visible range. We ob…
This paper details a novel, patent pending, abrasive machining manufacturing process for the formation of sub-millimetre holes in THGEMs, with the intended application in gaseous and dual-phase TPCs. Abrasive machining favours a non-ductile substrate such as glasses or ceramics. This innovative manufacturing process allows for unprecedented versatility in THGEM substrates, electrodes, and hole geometry and pattern. Consequently, THGEMs produced via abrasive machining can be tailored for specific properties, for example: high stiffness, low total thickness variation, radiopurity, moisture absor…
Proportional electroluminescence (EL) in noble gases has long been used in two-phase detectors for dark matter search, to record ionization signals induced by particle scattering in the noble-gas liquid (S2 signals). Until recently, it was believed that proportional electroluminescence was fully due to VUV emission of noble gas excimers produced in atomic collisions with excited atoms, the latter being in turn produced by drifting electrons. In this work we consider an additional mechanism of proportional electroluminescence, namely that of bremsstrahlung of drifting electrons scattered on neu…
We develop a novel approach for a Time Projection Chamber (TPC) concept suitable for deployment in kilotonne scale detectors, with a charge-readout system free from reconstruction ambiguities, and a robust TPC design that reduces high-voltage risks while increasing the coverage of the light collection system. This novel concept could be deployed as a Far Detector module in the Deep Underground Neutrino Experiment (DUNE) neutrino-oscillation experiment. For the charge-readout system, we use the charge-collection pixels and associated application-specific integrated circuits currently being deve…
Neutrinos are particles that interact rarely, so identifying them requires large detectors which produce lots of data. Processing this data with the computing power available is becoming more difficult as the detectors increase in size to reach their physics goals. In liquid argon time projection chambers (TPCs) the charged particles from neutrino interactions produce ionization electrons which drift in an electric field towards a series of collection wires, and the signal on the wires is used to reconstruct the interaction. The MicroBooNE detector currently collecting data at Fermilab has 800…
ProtoDUNE-DP is a 6x6x6 m3 liquid argon time-projection-chamber (LArTPC) operated at the Neutrino Platform at CERN in 2019-2020 as a prototype of the DUNE Far Detector. DUNE is a dual-site experiment for long-baseline neutrino oscillation studies, neutrino astrophysics and nucleon decay searches. The light signal in these detectors is crucial to provide precise timing capabilities. In ProtoDUNE-DP, scintillation light produced by cosmic muons inthe LArTPC is collected by the photomultiplier tubes (PMTs) placed up to 7 m away from the point of interaction. The scintillation light production and…
Neutrinos are particles that interact rarely, so identifying them requires large detectors which produce lots of data. Processing this data with the computing power available is becoming even more difficult as the detectors increase in size to reach their physics goals. Liquid argon time projection chamber (LArTPC) neutrino experiments are expected to grow in the next decade to have 100 times more wires than in currently operating experiments, and modernization of LArTPC reconstruction code, including parallelization both at data- and instruction-level, will help to mitigate this challenge. Th…
A measurement of ionization yields in noble-gas liquids is relevant to the energy calibration of nuclear recoil detectors for dark matter search and coherent neutrino-nucleus scattering experiments. In this work we further study the ionization yield of nuclear recoils in liquid Ar, using a two-phase detector with an electroluminescence gap and DD neutron generator. The ionization yields of nuclear recoils in liquid Ar were measured at 233 keV and electric fields of 0.56 and 0.62 kV/cm; their values amounted to 5.9 $\pm$ 0.8 and 7.4 $\pm$ 1 e$^-$/keV, respectively. The characteristic dependence…
The Deep Underground Neutrino Experiment (DUNE) will be the next generation long-baseline neutrino experiment. The far detector is designed as a complex of four LAr-TPC (Liquid Argon Time Projection Chamber) modules with 17 kt of liquid argon each. The development and validation of the first far detector technology is pursued through ProtoDUNE Single Phase (ProtoDUNE-SP), a 770 t LAr-TPC at CERN Neutrino Platform. Crucial in DUNE is the Photon Detection System that will ensure the trigger of non-beam events - proton decay, supernova neutrino burst and BSM searches - and will improve the timing…
We describe a novel ionization signal capture and waveform digitization scheme for kiloton-scale liquid argon Time Projection Chamber (TPC) detectors. The scheme is based on a pixel-scale self-triggering `charge integrate/reset' block, local clocks running at unconstrained frequencies and dynamically established data networks. The scheme facilitates detailed capture of waveforms of arbitrary complexity from a sequence of varying time intervals, each of which corresponds to a fixed charge integral. An absolute charge auto-calibration process based on intrinsic $^{39}$Ar decay current is a major…
Spectroscopic study of argon electroluminescence light with a wavelength-sensitive particle detector
Department of Physics, University of California, Davis（加州大学戴维斯分校物理系）；CIEMAT, Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas（能源、环境和技术研究研究中心）
Experimental observation of an extremely high electron lifetime with the ICARUS-T600 LAr-TPC
ICARUS T600探测器是经过多年研发活动实现的最大液态氩时间投影室（LAr-TPC），已在INFN Gran Sasso地下实验室安装并成功运行3年。最重要的问题之一是需要在液态氩中具有极低的残余电负性杂质含量，以便以非常小的衰减沿漂移路径传输由电离粒子产生的自由电子。氩再循环和纯化系统所采用的解决方案在氩纯度和超过15 ms的自由电子寿命方面实现了令人印象深刻的结果，相当于约万亿分之20的当量O2污染，这是涉及LAr-TPC的任何未来项目和更高探测器质量尺度的开发的里程碑。
Proportional electroluminescence (EL) in noble gases is a physical process routinely used in two-phase (liquid-gas) detectors for low-energy astroparticle-physics experiments. In this work, the time properties of visible-light EL in two-phase argon detectors have been systematically studied for the first time. In particular, two unusual slow components in the EL signal, with their contributions and time constants increasing with electric field, were observed. This puzzling property is not expected in any of the known mechanisms of photon and electron emission in two-phase media. Time constants…
