series of data samples was collected with the Belle Ⅱ detector at the SuperKEKB collider from March 2019 to June 2022.We determine the integrated luminosities of these data samples using three distinct methodologies ...series of data samples was collected with the Belle Ⅱ detector at the SuperKEKB collider from March 2019 to June 2022.We determine the integrated luminosities of these data samples using three distinct methodologies involving Bhabha(e^(+)e^(-)→e^(+)e^(-)(ny),digamma(e^(+)e^(-)→γγ(nγ),and dimuon(e^(+)e^(-)→μ^(+)μ^(-)(nγ)events.The total integrated luminosity obtained with Bhabha,digamma,and dimuon events is(426.88±0.03±2.61)fb^(-1),(429.28±0.03±2.62)fb^(-1),and(423.99±0.04±3.83)fb^(-1),where the first uncertainties are statistical and the second are systematic.The resulting total integrated luminosity obtained from the combination of the three methods is(427.87±2.01)fb^(-1).展开更多
A new search for two-neutrino double-beta(2νββ)decay of^(136)Xe to the 0+1 excited state of 136Ba is performed with the full EXO-200 dataset.A deep learning-based convolutional neural network is used to discriminat...A new search for two-neutrino double-beta(2νββ)decay of^(136)Xe to the 0+1 excited state of 136Ba is performed with the full EXO-200 dataset.A deep learning-based convolutional neural network is used to discriminate signal from background events.Signal detection efficiency is increased relative to previous searches by EXO-200 by more than a factor of two.With the addition of the Phase II dataset taken with an upgraded detector,the median 90%confidence level half-life sensitivity of 2νββdecay to the 0+1 state of 136Ba is 2.9×10^(24)yr using a total^(136)Xe exposure of 234.1 kg yr.No statistically significant evidence for 2νββdecay to the 0^(+)_(1)state is observed,leading to a lower limit of T2ν1/2(0^(+)→0^(+)_(1))>1.4×10^(24)yr at 90%confidence level,improved by 70%relative to the current world's best constraint.展开更多
基金supported by Higher Education and Science Committee of the Republic of Armenia(23LCG-1C011)Australian Research Council and Research(DP200101792,DP210101900,DP210102831,DE220100462,LE210100098,LE230100085)+41 种基金Austrian Federal Ministry of Education,Science and Research,Austrian Science Fund(P 34529,J 4731,J 4625,M 3153)Horizon 2020 ERC Starting(947006)“InterLeptons”Natural Sciences and Engineering Research Council of Canada,Compute Canada and CANARIENational Key R&D Program of China(2022YFA1601903)National Natural Science Foundation of China(11575017,11761141009,11705209,11975076,12135005,12150004,12161141008,12175041)Natural Science Foundation Project of Shandong Province,China(ZR2022JQ02)the Czech Science Foundation(22-18469S)and Charles University Grant Agency(246122)European Research Council,Seventh Framework(PIEF-GA-2013-622527)Horizon 2020 ERC-Advanced(Grant Nos.267104 and 884719)Horizon 2020 ERC-Consolidator(819127)Horizon 2020 Marie Sklodowska-Curie Grant Agreement(700525)“NIOBE”and(101026516)Horizon 2020 Marie Sklodowska-Curie RISE project JENNIFER2 Grant Agreement(822070)(European grants)L'Institut National de Physique Nucléaire et de Physique des Particules(IN2P3)du CNRS and L'Agence Nationale de la Recherche(ANR)(ANR-21-CE31-0009)(France)BMBF,DFG,HGF,MPG,and AvH Foundation(Germany)Department of Atomic Energy under Project Identification(RTI 4002)Department of Science and Technology,and UPES SEED funding programs(UPES/R&D-SEED-INFRA/17052023/01,UPES/R&D-SOE/20062022/06)(India)Israel Science Foundation(2476/17)U.S.-Israel Binational Science Foundation(2016113)Israel Ministry of Science(3-16543)Istituto Nazionale di Fisica Nucleare and the Research Grants BELLE2Japan Society for the Promotion of Science,Grant-in-Aid for Scientific Research(16H03968,16H03993,16H06492,16K05323,17H01133,17H05405,18K03621,18H03710,18H05226,19H00682,20H05850,20H05858,22H00144,22K14056,22K21347,23H05433,26220706,26400255)the Ministry of Education,Culture,Sports,Science,and Technology(MEXT)of JapanNational Research Foundation(NRF)of Korea(2016R1D1A1B02012900,2018R1A2B3003643,2018R1A6A1A06024970,2019R1I1A3A01058933,2021R1A6A1A03043957,2021R1F1A1060423,2021R1F1A1064008,2022R1A2C1003993,RS-2022-00197659)Radiation Science Research Institute,Foreign Large-Size Research Facility Application Supporting project,the Global Science Experimental Data Hub Center of the Korea Institute of Science and Technology Information and KREONET/GLORIADUniversiti Malaya RU grant,Akademi Sains Malaysia,and Ministry of Education MalaysiaFrontiers of Science Program(FOINS-296,CB-221329,CB-236394,CB-254409,CB-180023)SEP-CINVESTAV Research(237)(Mexico)the Polish Ministry of Science and Higher Education and the National Science Centerthe Ministry of Science and Higher Education of the Russian Federation and the HSE University Basic Research Program,MoscowUniversity of Tabuk Research(S-0256-1438,S-0280-1439)(Saudi Arabia)Slovenian Research Agency and Research(J1-9124,P1-0135)Agencia Estatal de Investigacion,Spain(RYC2020-029875-I)Generalitat Valenciana,Spain(CIDEGENT/2018/020)The Knut and Alice Wallenberg Foundation(Sweden),(2021.0174,2021.0299)National Science and Technology Council,and Ministry of EducationThailand Center of Excellence in PhysicsTUBITAK ULAKBIM(Turkey)National Research Foundation of Ukraine,(2020.02/0257)Ministry of Education and Science of Ukrainethe U.S.National Science Foundation and Research(PHY-1913789,PHY-2111604)the U.S.Department of Energy and Research Awards(DE-AC06-76RLO1830,DE-SC0007983,DESC0009824,DE-SC0009973,DE-SC0010007,DE-SC0010073,DE-SC0010118,DE-SC0010504,DE-SC0011784,DE-SC0012704,DE-SC0019230,DESC0021274,DE-SC0021616,DE-SC0022350,DE-SC0023470)the Vietnam Academy of Science and Technology(VAST)(NVCC.05.12/22-23,DL0000.02/24-25)。
文摘series of data samples was collected with the Belle Ⅱ detector at the SuperKEKB collider from March 2019 to June 2022.We determine the integrated luminosities of these data samples using three distinct methodologies involving Bhabha(e^(+)e^(-)→e^(+)e^(-)(ny),digamma(e^(+)e^(-)→γγ(nγ),and dimuon(e^(+)e^(-)→μ^(+)μ^(-)(nγ)events.The total integrated luminosity obtained with Bhabha,digamma,and dimuon events is(426.88±0.03±2.61)fb^(-1),(429.28±0.03±2.62)fb^(-1),and(423.99±0.04±3.83)fb^(-1),where the first uncertainties are statistical and the second are systematic.The resulting total integrated luminosity obtained from the combination of the three methods is(427.87±2.01)fb^(-1).
文摘A new search for two-neutrino double-beta(2νββ)decay of^(136)Xe to the 0+1 excited state of 136Ba is performed with the full EXO-200 dataset.A deep learning-based convolutional neural network is used to discriminate signal from background events.Signal detection efficiency is increased relative to previous searches by EXO-200 by more than a factor of two.With the addition of the Phase II dataset taken with an upgraded detector,the median 90%confidence level half-life sensitivity of 2νββdecay to the 0+1 state of 136Ba is 2.9×10^(24)yr using a total^(136)Xe exposure of 234.1 kg yr.No statistically significant evidence for 2νββdecay to the 0^(+)_(1)state is observed,leading to a lower limit of T2ν1/2(0^(+)→0^(+)_(1))>1.4×10^(24)yr at 90%confidence level,improved by 70%relative to the current world's best constraint.