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Adhikari P, Adhikari G, Souza EBD, Carlin N, Choi S, Choi WQ, Djamal M, Ezeribe AC, Ha C, Hahn IS, Hubbard AJF, Jeon EJ, Jo JH, Joo HW, Kang WG, Kauer M, Kang WS, Kim BH, Kim H, Kim HJ, Kim KW, Kim MC, Kim NY, Kim SK, Kim YD, Kim YH, Kudryavtsev VA, Lee HS, Lee J, Lee JY, Lee MH, Leonard DS, Lynch WA, Maruyama RH, Mouton F, Olsen SL, Park HK, Park HS, Park JS, Park KS, Pettus W, Prihtiadi H, Ra S, Rott C, Scarff A, Spooner NJC, Thompson WG, Yang L, Yong SH. Background model for the NaI(Tl) crystals in COSINE-100. Eur Phys J C Part Fields 2018; 78:490. [PMID: 30956554 PMCID: PMC6424159 DOI: 10.1140/epjc/s10052-018-5970-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Accepted: 06/01/2018] [Indexed: 06/09/2023]
Abstract
The COSINE-100 dark matter search experiment is an array of NaI(Tl) crystal detectors located in the Yangyang Underground Laboratory (Y2L). To understand measured backgrounds in the NaI(Tl) crystals we have performed Monte Carlo simulations using the Geant4 toolkit and developed background models for each crystal that consider contributions from both internal and external sources, including cosmogenic nuclides. The background models are based on comparisons of measurement data with Monte Carlo simulations that are guided by a campaign of material assays and are used to evaluate backgrounds and identify their sources. The average background level for the six crystals (70 kg total mass) that are studied is 3.5 counts/day/keV/kg in the (2-6) keV energy interval. The dominant contributors in this energy region are found to be 210 Pb and 3 H.
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Affiliation(s)
- P. Adhikari
- Department of Physics and Astronomy, Sejong University, Seoul, 05006 South Korea
| | - G. Adhikari
- Department of Physics and Astronomy, Sejong University, Seoul, 05006 South Korea
| | - E. Barbosa de Souza
- Wright Laboratory, Department of Physics, Yale University, New Haven, CT 06520 USA
| | - N. Carlin
- Physics Institute, University of São Paulo, São Paulo, 05508-090 Brazil
| | - S. Choi
- Department of Physics and Astronomy, Seoul National University, Seoul, 08826 Republic of Korea
| | - W. Q. Choi
- Korea Institue of Science and Technology Information, Daejeon, 34141 Republic of Korea
| | - M. Djamal
- Department of Physics, Bandung Institute of Technology, Bandung, 40132 Indonesia
| | - A. C. Ezeribe
- Department of Physics and Astronomy, University of Sheffield, Sheffield, S3 7RH UK
| | - C. Ha
- Center for Underground Physics, Institute for Basic Science (IBS), Daejeon, 34126 Republic of Korea
| | - I. S. Hahn
- Department of Science Education, Ewha Womans University, Seoul, 03760 Republic of Korea
| | - A. J. F. Hubbard
- Wright Laboratory, Department of Physics, Yale University, New Haven, CT 06520 USA
| | - E. J. Jeon
- Center for Underground Physics, Institute for Basic Science (IBS), Daejeon, 34126 Republic of Korea
| | - J. H. Jo
- Wright Laboratory, Department of Physics, Yale University, New Haven, CT 06520 USA
| | - H. W. Joo
- Department of Physics and Astronomy, Seoul National University, Seoul, 08826 Republic of Korea
| | - W. G. Kang
- Center for Underground Physics, Institute for Basic Science (IBS), Daejeon, 34126 Republic of Korea
| | - M. Kauer
- Department of Physics and Wisconsin IceCube Particle Astrophysics Center, University of Wisconsin-Madison, Madison, WI 53706 USA
| | - W. S. Kang
- Department of Physics, Sungkyunkwan University, Seoul, 16419 Republic of Korea
| | - B. H. Kim
- Center for Underground Physics, Institute for Basic Science (IBS), Daejeon, 34126 Republic of Korea
| | - H. Kim
- Center for Underground Physics, Institute for Basic Science (IBS), Daejeon, 34126 Republic of Korea
| | - H. J. Kim
- Department of Physics, Kyungpook National University, Daegu, 41566 Republic of Korea
| | - K. W. Kim
- Center for Underground Physics, Institute for Basic Science (IBS), Daejeon, 34126 Republic of Korea
| | - M. C. Kim
- Department of Physics, Sungkyunkwan University, Seoul, 16419 Republic of Korea
| | - N. Y. Kim
- Center for Underground Physics, Institute for Basic Science (IBS), Daejeon, 34126 Republic of Korea
| | - S. K. Kim
- Department of Physics and Astronomy, Seoul National University, Seoul, 08826 Republic of Korea
| | - Y. D. Kim
- Department of Physics and Astronomy, Sejong University, Seoul, 05006 South Korea
- Center for Underground Physics, Institute for Basic Science (IBS), Daejeon, 34126 Republic of Korea
| | - Y. H. Kim
- Center for Underground Physics, Institute for Basic Science (IBS), Daejeon, 34126 Republic of Korea
- Korea Research Institute of Standards and Science, Daejeon, 34113 Republic of Korea
| | - V. A. Kudryavtsev
- Department of Physics and Astronomy, University of Sheffield, Sheffield, S3 7RH UK
| | - H. S. Lee
- Center for Underground Physics, Institute for Basic Science (IBS), Daejeon, 34126 Republic of Korea
| | - J. Lee
- Center for Underground Physics, Institute for Basic Science (IBS), Daejeon, 34126 Republic of Korea
| | - J. Y. Lee
- Department of Physics and Astronomy, Seoul National University, Seoul, 08826 Republic of Korea
| | - M. H. Lee
- Center for Underground Physics, Institute for Basic Science (IBS), Daejeon, 34126 Republic of Korea
| | - D. S. Leonard
- Center for Underground Physics, Institute for Basic Science (IBS), Daejeon, 34126 Republic of Korea
| | - W. A. Lynch
- Department of Physics and Astronomy, University of Sheffield, Sheffield, S3 7RH UK
| | - R. H. Maruyama
- Wright Laboratory, Department of Physics, Yale University, New Haven, CT 06520 USA
| | - F. Mouton
- Department of Physics and Astronomy, University of Sheffield, Sheffield, S3 7RH UK
| | - S. L. Olsen
- Center for Underground Physics, Institute for Basic Science (IBS), Daejeon, 34126 Republic of Korea
| | - H. K. Park
- Department of Accelerator Science, Graduate School, Korea University, Sejong, 30019 South Korea
| | - H. S. Park
- Korea Research Institute of Standards and Science, Daejeon, 34113 Republic of Korea
| | - J. S. Park
- Center for Underground Physics, Institute for Basic Science (IBS), Daejeon, 34126 Republic of Korea
| | - K. S. Park
- Center for Underground Physics, Institute for Basic Science (IBS), Daejeon, 34126 Republic of Korea
| | - W. Pettus
- Wright Laboratory, Department of Physics, Yale University, New Haven, CT 06520 USA
| | - H. Prihtiadi
- Department of Physics, Bandung Institute of Technology, Bandung, 40132 Indonesia
| | - S. Ra
- Center for Underground Physics, Institute for Basic Science (IBS), Daejeon, 34126 Republic of Korea
| | - C. Rott
- Department of Physics, Sungkyunkwan University, Seoul, 16419 Republic of Korea
| | - A. Scarff
- Department of Physics and Astronomy, University of Sheffield, Sheffield, S3 7RH UK
| | - N. J. C. Spooner
- Department of Physics and Astronomy, University of Sheffield, Sheffield, S3 7RH UK
| | - W. G. Thompson
- Wright Laboratory, Department of Physics, Yale University, New Haven, CT 06520 USA
| | - L. Yang
- Department of Physics, University of Illinois at Urbana-Champaign, Urbana IL, 61801 USA
| | - S. H. Yong
- Center for Underground Physics, Institute for Basic Science (IBS), Daejeon, 34126 Republic of Korea
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Choi JH, Choi WQ, Choi Y, Jang HI, Jang JS, Jeon EJ, Joo KK, Kim BR, Kim HS, Kim JY, Kim SB, Kim SY, Kim W, Kim YD, Ko Y, Lee DH, Lim IT, Pac MY, Park IG, Park JS, Park RG, Seo H, Seo SH, Seon YG, Shin CD, Siyeon K, Yang JH, Yeo IS, Yu I. Observation of Energy and Baseline Dependent Reactor Antineutrino Disappearance in the RENO Experiment. Phys Rev Lett 2016; 116:211801. [PMID: 27284648 DOI: 10.1103/physrevlett.116.211801] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Indexed: 06/06/2023]
Abstract
The RENO experiment has analyzed about 500 live days of data to observe an energy dependent disappearance of reactor ν[over ¯]_{e} by comparing their prompt signal spectra measured in two identical near and far detectors. In the period between August of 2011 and January of 2013, the far (near) detector observed 31 541 (290 775) electron antineutrino candidate events with a background fraction of 4.9% (2.8%). The measured prompt spectra show an excess of reactor ν[over ¯]_{e} around 5 MeV relative to the prediction from a most commonly used model. A clear energy and baseline dependent disappearance of reactor ν[over ¯]_{e} is observed in the deficit of the observed number of ν[over ¯]_{e}. Based on the measured far-to-near ratio of prompt spectra, we obtain sin^{2}2θ_{13}=0.082±0.009(stat)±0.006(syst) and |Δm_{ee}^{2}|=[2.62_{-0.23}^{+0.21}(stat)_{-0.13}^{+0.12}(syst)]×10^{-3} eV^{2}.
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Affiliation(s)
- J H Choi
- Department of Radiology, Dongshin University, Naju 58245, Korea
| | - W Q Choi
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Korea
| | - Y Choi
- Department of Physics, Sungkyunkwan University, Suwon 16419, Korea
| | - H I Jang
- Department of Fire Safety, Seoyeong University, Gwangju 61268, Korea
| | - J S Jang
- GIST College, Gwangju Institute of Science and Technology, Gwangju 61005, Korea
| | - E J Jeon
- Institute for Basic Science, Daejeon 34047, Korea
- Department of Physics and Astronomy, Sejong University, Seoul 05006, Korea
| | - K K Joo
- Institute for Universe and Elementary Particles, Chonnam National University, Gwangju 61186, Korea
| | - B R Kim
- Institute for Universe and Elementary Particles, Chonnam National University, Gwangju 61186, Korea
| | - H S Kim
- Department of Physics and Astronomy, Sejong University, Seoul 05006, Korea
| | - J Y Kim
- Institute for Universe and Elementary Particles, Chonnam National University, Gwangju 61186, Korea
| | - S B Kim
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Korea
| | - S Y Kim
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Korea
| | - W Kim
- Department of Physics, Kyungpook National University, Daegu 41566, Korea
| | - Y D Kim
- Institute for Basic Science, Daejeon 34047, Korea
- Department of Physics and Astronomy, Sejong University, Seoul 05006, Korea
| | - Y Ko
- Department of Physics, Chung Ang University, Seoul 06974, Korea
| | - D H Lee
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Korea
| | - I T Lim
- Institute for Universe and Elementary Particles, Chonnam National University, Gwangju 61186, Korea
| | - M Y Pac
- Department of Radiology, Dongshin University, Naju 58245, Korea
| | - I G Park
- Department of Physics, Gyeongsang National University, Jinju 52828, Korea
| | - J S Park
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Korea
| | - R G Park
- Institute for Universe and Elementary Particles, Chonnam National University, Gwangju 61186, Korea
| | - H Seo
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Korea
| | - S H Seo
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Korea
| | - Y G Seon
- Department of Physics, Kyungpook National University, Daegu 41566, Korea
| | - C D Shin
- Institute for Universe and Elementary Particles, Chonnam National University, Gwangju 61186, Korea
| | - K Siyeon
- Department of Physics, Chung Ang University, Seoul 06974, Korea
| | - J H Yang
- Department of Physics, Sungkyunkwan University, Suwon 16419, Korea
| | - I S Yeo
- Institute for Universe and Elementary Particles, Chonnam National University, Gwangju 61186, Korea
| | - I Yu
- Department of Physics, Sungkyunkwan University, Suwon 16419, Korea
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