Low-Energy Radon Backgrounds from Electrode Grids in Dual-Phase Xenon TPCs
SLAC National Accelerator Laboratory（斯坦福直线加速器中心）；Kavli Institute for Particle Astrophysics and Cosmology, Stanford University（卡弗里粒子天体物理与宇宙学研究所，斯坦福大学）；University College London (UCL)（伦敦大学学院）；Brown University（布朗大学）；University of Wisconsin-Madison（威斯康星大学麦迪逊分校）；University of California, Santa Barbara（加州大学圣塔芭芭拉分校）；Imperial College London（帝国理工学院）；University of Maryland（马里兰大学）
D. S. Akerib, A. K. Al Musalhi, F. Alder, B. J. Almquist, S. Alsum, C. S. Amarasinghe, A. Ames, T. J. Anderson, N. Angelides, H. M. Araújo, J. E. Armstrong, M. … 展开作者
D. S. Akerib, A. K. Al Musalhi, F. Alder, B. J. Almquist, S. Alsum, C. S. Amarasinghe, A. Ames, T. J. Anderson, N. Angelides, H. M. Araújo, J. E. Armstrong, M. Arthurs, X. Bai, A. Baker, J. Balajthy, S. Balashov, J. Bang, J. W. Bargemann, E. E. Barillier, A. Baxter, K. Beattie, T. Benson, E. P. Bernard, A. Bernstein, A. Bhatti, T. P. Biesiadzinski, H. J. Birch, E. Bishop, G. M. Blockinger, E. M. Boulton, B. Boxer, C. A. J. Brew, P. Brás, S. Burdin, D. Byram, M. C. Carmona-Benitez, M. Carter, C. Chan, A. Chawla, H. Chen, Y. T. Chin, N. I. Chott, S. Contreras, M. V. Converse, R. Coronel, A. Cottle, G. Cox, D. Curran, J. E. Cutter, C. E. Dahl, I. Darlington, S. Dave, A. David, J. Delgaudio, S. Dey, L. de Viveiros, L. Di Felice, C. Ding, J. E. Y. Dobson, E. Druszkiewicz, S. Dubey, C. L. Dunbar, S. R. Eriksen, A. Fan, N. M. Fearon, N. Fieldhouse, S. Fiorucci, H. Flaecher, E. D. Fraser, T. M. A. Fruth, P. W. Gaemers, R. J. Gaitskell, A. Geffre, J. Genovesi, C. Ghag, J. Ghamsari, A. Ghosh, S. Ghosh, R. Gibbons, M. G. D. Gilchriese, S. Gokhale, J. Green, M. G. D. van der Grinten, C. Gwilliam, J. J. Haiston, C. R. Hall, T. Hall, R. H Hampp, E. Hartigan-O'Connor, S. J. Haselschwardt, M. A. Hernandez, S. A. Hertel, D. P. Hogan, G. J. Homenides, M. Horn, D. Q. Huang, D. Hunt, C. M. Ignarra, R. G. Jacobsen, E. Jacquet, O. Jahangir, R. S. James, K. Jenkins, W. Ji, A. C. Kaboth, A. C. Kamaha, K. Kamdin, M. K. Kannichankandy, K. Kazkaz, D. Khaitan, A. Khazov, J. Kim, Y. D. Kim, J. Kingston, D. Kodroff, E. V. Korolkova, H. Kraus, S. Kravitz, L. Kreczko, V. A. Kudryavtsev, C. Lawes, E. Leason, D. S. Leonard, K. T. Lesko, C. Levy, J. Liao, J. Lin, A. Lindote, R. Linehan, W. H. Lippincott, J. Long, M. I. Lopes, W. Lorenzon, C. Lu, S. Luitz, W. Ma, V. Mahajan, P. A. Majewski, A. Manalaysay, R. L. Mannino, N. Marangou, R. J. Matheson, C. Maupin, M. E. McCarthy, G. McDowell, D. N. McKinsey, J. McLaughlin, J. B. McLaughlin, R. McMonigle, D. -M. Mei, B. Mitra, E. Mizrachi, M. E. Monzani, K. Morå, J. A. Morad, E. Morrison, B. J. Mount, M. Murdy, A. St. J. Murphy, A. Naylor, C. Nehrkorn, H. N. Nelson, F. Neves, A. Nguyen, A. Nilima, C. L. O'Brien, F. H. O'Shea, I. Olcina, K. C. Oliver-Mallory, J. Orpwood, K. Y Oyulmaz, K. J. Palladino, N. J. Pannifer, N. Parveen, S. J. Patton, B. Penning, G. Pereira, E. Perry, T. Pershing, A. Piepke, S. S. Poudel, Y. Qie, J. Reichenbacher, C. A. Rhyne, Q. Riffard, G. R. C. Rischbieter, E. Ritchey, H. S. Riyat, R. Rosero, P. Rossiter, N. J. Rowe, T. Rushton, D. Rynders, S. Saltão, D. Santone, A. B. M. R. Sazzad, R. W. Schnee, G. Sehr, B. Shafer, S. Shaw, W. Sherman, K. Shi, T. Shutt, C. Silva, G. Sinev, J. Siniscalco, A. M. Slivar, R. Smith, A. M. Softley-Brown, M. Solmaz, V. N. Solovov, P. Sorensen, J. Soria, A. Stevens, T. J. Sumner, A. Swain, N. Swanson, M. Szydagis, D. J. Taylor, R. Taylor, W. C. Taylor, B. P. Tennyson, P. A. Terman, D. R. Tiedt, M. Timalsina, W. H. To, Z. Tong, D. R. Tovey, J. Tranter, M. Trask, K. Trengove, M. Tripathi, L. Tvrznikova, U. Utku, A. Usón, A. Vacheret, A. C. Vaitkus, O. Valentino, V. Velan, A. Wang, J. J. Wang, Y. Wang, R. C. Webb, L. Weeldreyer, J. T. White, T. J. Whitis, K. Wild, M. Williams, J. Winnicki, M. S. Witherell, L. Wolf, F. L. H. Wolfs, S. Woodford, D. Woodward, C. J. Wright, Q. Xia, X. Xiang, J. Xu, Y. Xu, M. Yeh, D. Yeum, J. Young, W. Zha, C. Zhang, H. Zhang, T. Zhang, Y. Zhou
The dual-phase xenon time projection chamber (TPC) is a powerful technology to detect rare interactions such as scatters of dark matter particles on nuclei. In particular, the built-in gain of ionization signals in a dual-phase TPC makes it sensitive to events in the few-electron regime, as expected from low-mass dark matter interactions. The pursuit of this low-energy sensitivity through ionization-only signal detection has so far been hindered by excessive electron backgrounds observed across experiments. Much of this background is attributed to the plate-out of $^{222}$Rn decay chain isotopes on the high voltage electrode grid surfaces that span the full cross section of the TPC. This work presents a first-principle model constructed for this background, the predictions of which are consistent with data from the LZ and LUX experiments. We then discuss mitigation strategies of this background in future dual-phase TPCs and the possibility of applying this grid background model to ionization-only dark matter searches.
Xenon time projection chambers (TPCs) have become a well-established detection technology for neutrinoless double beta decay searches in $^{136}$Xe. I discuss the motivations for this choice. I describe the status and prospects of both liquid and gaseous xenon TPC projects for double beta decay.
This article reviews the application of high pressure gas xenon (HPXe) time projection chambers to neutrinoless double beta decay experiments. First, the fundamentals of the technology and the historical development of the field are discussed. Then, the state of the art is presented, including the prospects for the next generation of experiments with masses in the ton scale.
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 …
An online cryogenic distillation system for the removal of krypton and radon from xenon was designed and constructed for PandaX-4T, a highly sensitive dark matter detection experiment. The krypton content in a commercial xenon product is expected to be reduced by 7 orders of magnitude with 99% xenon collection efficiency at a flow rate of 10 kg/h by design. The same system can reduce radon content in xenon by reversed operation, with an expected radon reduction factor of about 1.8 in PandaX-4T under a flow rate of 56.5 kg/h. The commissioning of this system was completed, with krypton and rado…
Within the framework of xenon-based double beta decay experiments, we propose the possibility to improve the background rejection of an electroluminescent Time Projection Chamber (EL TPC) by reducing the diffusion of the drifting electrons while keeping nearly intact the energy resolution of a pure xenon EL TPC. Based on state-of-the-art microscopic simulations, a substantial addition of helium, around 10 or 15~\%, may reduce drastically the transverse diffusion down to 2.5~mm/$\sqrt{\mathrm{m}}$ from the 10.5~mm/$\sqrt{\mathrm{m}}$ of pure xenon. The longitudinal diffusion remains around 4~mm…
We have built and operated a crystalline/vapor xenon TPC, with the goal of improving searches for dark matter. The motivation for this instrument is the fact that beta decays from the radon decay chain to the ground state presently limit the state-of-the-art liquid/vapor xenon experiments. In contrast, a crystalline xenon target has the potential to tag and reject radon-chain backgrounds, due to the time and energy signature of their decays. The present article is the first demonstration of a crystalline/vapor xenon TPC with electroluminescence (gas gain) for the electron signal readout. It al…
The NEXT experiment aims at searching for the hypothetical neutrinoless double-beta decay from the ${}^{136}$Xe isotope using a high-purity xenon TPC. Efficient discrimination of the events through pattern recognition of the topology of primary ionisation tracks is a major requirement for the experiment. However, it is limited by the diffusion of electrons. It is known that the addition of a small fraction of a molecular gas to xenon reduces electron diffusion. On the other hand, the electroluminescence (EL) yield drops and the achievable energy resolution may be compromised. We have studied t…
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…
Predicting the single-site and multi-site event discrimination power of dual-phase time projection chambers
Lawrence Livermore National Laboratory（劳伦斯利弗莫尔国家实验室）；Stanford University（斯坦福大学）；University of California San Diego（加州大学圣迭戈分校）；SLAC National Accelerator Laboratory（斯坦福直线加速器中心）；Washington University in St. Louis（华盛顿大学圣路易斯分校）
NEXT (Neutrino Experiment with a Xenon TPC) is an experimental program whose goals are to discover neutrinoless double beta decay using $^{136}$Xe in high pressure xenon TPCs with electroluminescent readout. In this paper, results from the NEXT-White detector, which is currently taking data at Laboratorio Subterráneo de Canfranc (LSC) will be reported. The prospects for the NEXT-100 apparatus, scheduled to start operations in 2020, as well as the plans to extend the technology to large and ultra-low background detectors needed to fully explore the inverse hierarchy of neutrino masses, will als…
Pattern recognition of $^{136}$Xe double beta decay events and background discrimination in a high pressure Xenon TPC
高压气体探测器为检测罕见事件提供了优势，其中背景减少至关重要。高压氙气时间投影室（TPC）对136氚的无中微子双β衰变具有很好的能量分辨率和详细的拓扑信息。气态氙中136氘的双β衰变事件的电离拓扑结构具有由两个离散电子径迹定义的特征形状，这两个电子径迹最终形成两个较高电离电荷密度的斑点。通过适当的像素化读出，这种拓扑信息对于执行强大的背景区分是非常宝贵的。在这项研究中，我们进行了详细的模拟信号的拓扑结构，以及竞争的拓扑结构，从伽马事件，通常构成在这些能量的背景。我们基于图论概念定义了可观测量，并开发了自动判别算法，该算法将背景水平降低了约三个数量级，同时保持了40%的信号效率。这一结果支持了目前或未来基于气体TPC的双β实验的竞争力，例如目前正在Canfranc Subaragio de Canfranc（LSC）建造的中微子氙TPC（NEXT）。
The potential of discrimination methods in a high pressure xenon TPC for the search of the neutrinoless double-beta decay of Xe-136
在寻找$^{136}$氘的无中微子双β衰变过程中，高压氙时间投影室（HPXe-TPC）与液体氙TPC相比具有两个优势：更好的能量分辨率和拓扑特征，这可以提供额外的背景事件区分。PandaX-III实验最近提出了一个基于Micromegas读出平面的200 kg HPXe-TPC，位于中国锦屏地下实验室。它的探测概念基于T-REX项目中获得的两个结果：Micromegas读数可以在极低的放射性水平下构建;在现实实验条件下在10 bar的氙-三甲胺中操作已证明在感兴趣区域的能量分辨率为3% FWHM。在这项工作中，两个歧视的方法被施加到一个通用的200公斤HPXe-TPC的模拟信号和背景数据，基于两个著名的图论算法：识别的连接和搜索的最长路径。拒绝因子大于100的小像素尺寸和40%的信号效率。此外，一个新的可观察的（斑点电荷密度）拒绝更好的表面污染，这使得触发信号（$T_0$）的使用在这个实验中不是必要的。
The idea of a hermetic quartz chamber in a dual-phase xenon time projection chamber (TPC) has the potential to improve the detector sensitivity for direct dark matter searches in the future. A major challenge facing TPC detectors in future dark matter experiments will be the reduction of the internal background such as $^{222}$Rn and the deterioration of the ionization signal due to electronegative impurities. The hermetic quartz chamber can isolate the TPC's sensitive volume from external interference and is thus expected to prevent contamination caused by the radioactive and electronegative …
Dark matter searches using dual-phase xenon time-projection chambers (LXe-TPCs) rely on their ability to reject background electron recoils (ERs) while searching for signal-like nuclear recoils (NRs). ER response is typically calibrated using $β$-decay sources, such as tritium, but these calibrations do not characterize events accompanied by an atomic vacancy, as in solar neutrino scatters off inner shell electrons. Such events lead to emission of X-rays and Auger electrons, resulting in higher electron-ion recombination and thus a more NR-like response than inferred from $β$-decay calibration…
We have developed a low-energy electron recoil (ER) calibration method with $^{220}$Rn for the PandaX-II detector. $^{220}$Rn, emanated from natural thorium compounds, was fed into the detector through the xenon purification system. From 2017 to 2019, we performed three dedicated calibration campaigns with different radon sources. We studied the detector response to $α$, $β$, and $γ$ particles with focus on low energy ER events. During the runs in 2017 and 2018, the amount of radioactivity of $^{222}$Rn were on the order of 1\% of that of $^{220}$Rn and thorium particulate contamination was ne…
The throttling refrigeration system for high cooling power recovery of the PandaX-xT cryogenic distillation system for radon removal
SJTU Paris Elite Institute of Technology, Shanghai Jiao Tong University（上海交通大学巴黎卓越工程师学院）；New Cornerstone Science Laboratory, Tsung-Dao Lee Institute, Shanghai Jiao Tong University（新Cornerstone科学实验室，汤川秀树研究所，上海交通大学）；School of Physics and Astronomy, Shanghai Jiao Tong University（上海交通大学物理与天文学院）；Shanghai Jiao Tong University Sichuan Research Institute（上海交通大学四川研究院）；Jinping Deep Underground Frontier Science and Dark Matter Key Laboratory of Sichuan Province（四川省锦屏深地下前沿科学与暗物质重点实验室）；Vacree Technologies Co., Ltd.（沃瑞科技有限公司）；School of Chemical Engineering, Zhengzhou University（郑州大学化学工程与应用学院）；School of Physics, Sun Yat-Sen University（中山大学物理学院）；Department of Physics, University of Maryland, College Park（马里兰大学帕克分校物理系）；Yalong River Hydropower Development Company, Ltd.（雅砻江流域水电开发有限公司）
Dual-phase noble-gas time projection chambers (TPCs) have improved the sensitivities for dark matter direct search in past decades. The capability of TPCs to reconstruct 3-D vertexes of keV scale recoilings is one of the most advantageous features. In this work, we develop two horizontal position reconstruction algorithms for the PandaX-II dark matter search experiment using the dual-phase liquid xenon TPC. Both algorithms are optimized by the $^{83m}$Kr calibration events and use photon distribution of ionization signals among photomultiplier tubes to infer the positions. According to the eve…
Dark Matter (DM) is one of the most critical questions to be understood and answered in fundamental physics today. Observations with varied astronomical and cosmological technologies already pinned down that DM exists in the Universe, the Milky Way, and the Solar System. However, the understanding of DM under the language of elementary physics is still in progress. DM direct detection aims to test the interactive cross-section between galactic DM particles and an underground detector's nucleons. Although Weakly Interactive Massive Particles (WIMPs) is the most discussed DM candidate, the null-…
