Author
B. S. Yang
Bio: B. S. Yang is an academic researcher from Seoul National University. The author has contributed to research in topics: Neutrino & Super-Kamiokande. The author has an hindex of 23, co-authored 26 publications receiving 4589 citations.
Topics: Neutrino, Super-Kamiokande, Neutrino oscillation, Muon, Lepton
Papers
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TL;DR: The RENO experiment has observed the disappearance of reactor electron antineutrinos, consistent with neutrino oscillations, with a significance of 4.9 standard deviations.
Abstract: The RENO experiment has observed the disappearance of reactor electron antineutrinos, consistent with neutrino oscillations, with a significance of 4.9 standard deviations. Antineutrinos from six $2.8\text{ }\text{ }{\mathrm{GW}}_{\mathrm{th}}$ reactors at the Yonggwang Nuclear Power Plant in Korea, are detected by two identical detectors located at 294 and 1383 m, respectively, from the reactor array center. In the 229 d data-taking period between 11 August 2011 and 26 March 2012, the far (near) detector observed 17102 (154088) electron antineutrino candidate events with a background fraction of 5.5% (2.7%). The ratio of observed to expected numbers of antineutrinos in the far detector is $0.920\ifmmode\pm\else\textpm\fi{}0.009(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.014(\mathrm{syst})$. From this deficit, we determine ${sin }^{2}2{\ensuremath{\theta}}_{13}=0.113\ifmmode\pm\else\textpm\fi{}0.013(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.019(\mathrm{syst})$ based on a rate-only analysis.
1,979 citations
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TL;DR: The results of the second phase of the Super-Kamiokande solar neutrino measurement are presented and compared to the first phase in this paper, showing no evidence of systematic tendencies between the first and second phases.
Abstract: The results of the second phase of the Super-Kamiokande solar neutrino measurement are presented and compared to the first phase. The solar neutrino flux spectrum and time variation as well as oscillation results are statistically consistent with the first phase and do not show spectral distortion. The time-dependent flux measurement of the combined first and second phases coincides with the full period of solar cycle 23 and shows no correlation with solar activity. The measured {sup 8}B total flux is (2.38{+-}0.05(stat.){sub -0.15}{sup +0.16}(sys.))x10{sup 6} cm{sup -2} s{sup -1} and the day-night difference is found to be (-6.3{+-}4.2(stat.){+-}3.7(sys.))%. There is no evidence of systematic tendencies between the first and second phases.
439 citations
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University of Tokyo1, Kyoto University2, University of California, Irvine3, Autonomous University of Madrid4, Boston University5, University of Wisconsin-Madison6, Brookhaven National Laboratory7, California State University, Dominguez Hills8, Chonnam National University9, Duke University10, Fukuoka Institute of Technology11, Gifu University12, Kanagawa University13, Kobe University14, Miyagi University of Education15, Nagoya University16, Stony Brook University17, Niigata University18, Okayama University19, Osaka University20, Seoul National University21, Shizuoka University22, Sungkyunkwan University23, Tokai University24, Tsinghua University25, University of Warsaw26, University of Washington27, University of Minnesota28
TL;DR: The results of the third phase of the Super-Kamiokande solar neutrino measurement are presented and compared to the first and second phase results in this article, where improved detector calibrations, a full detector simulation, and improved analysis methods are estimated to be approximately 2.1%, which is about two thirds of the systematic uncertainty for the first phase.
Abstract: The results of the third phase of the Super-Kamiokande solar neutrino measurement are presented and compared to the first and second phase results. With improved detector calibrations, a full detector simulation, and improved analysis methods, the systematic uncertainty on the total neutrino flux is estimated to be $\ifmmode\pm\else\textpm\fi{}2.1%$, which is about two thirds of the systematic uncertainty for the first phase of Super-Kamiokande. The observed $^{8}\mathrm{B}$ solar flux in the 5.0 to 20 MeV total electron energy region is $2.32\ifmmode\pm\else\textpm\fi{}0.04(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.05(\mathrm{sys})\ifmmode\times\else\texttimes\fi{}{10}^{6}\text{ }\text{ }{\mathrm{cm}}^{\ensuremath{-}2}\text{ }{\mathrm{sec}}^{\ensuremath{-}1}$ under the assumption of pure electron-flavor content, in agreement with previous measurements. A combined oscillation analysis is carried out using SK-I, II, and III data, and the results are also combined with the results of other solar neutrino experiments. The best-fit oscillation parameters are obtained to be ${sin }^{2}{\ensuremath{\theta}}_{12}={0.30}_{\ensuremath{-}0.01}^{+0.02}({tan }^{2}{\ensuremath{\theta}}_{12}={0.42}_{\ensuremath{-}0.02}^{+0.04})$ and $\ensuremath{\Delta}{m}_{21}^{2}={6.2}_{\ensuremath{-}1.9}^{+1.1}\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}\text{ }\text{ }{\mathrm{eV}}^{2}$. Combined with KamLAND results, the best-fit oscillation parameters are found to be ${sin }^{2}{\ensuremath{\theta}}_{12}=0.31\ifmmode\pm\else\textpm\fi{}0.01({tan }^{2}{\ensuremath{\theta}}_{12}=0.44\ifmmode\pm\else\textpm\fi{}0.03)$ and $\ensuremath{\Delta}{m}_{21}^{2}=7.6\ifmmode\pm\else\textpm\fi{}0.2\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}\text{ }\text{ }{\mathrm{eV}}^{2}$. The $^{8}\mathrm{B}$ neutrino flux obtained from global solar neutrino experiments is $5.3\ifmmode\pm\else\textpm\fi{}0.2(\mathrm{stat}+\mathrm{sys})\ifmmode\times\else\texttimes\fi{}{10}^{6}\text{ }\text{ }{\mathrm{cm}}^{\ensuremath{-}2}\text{ }{\mathrm{s}}^{\ensuremath{-}1}$, while the $^{8}\mathrm{B}$ flux becomes $5.1\ifmmode\pm\else\textpm\fi{}0.1(\mathrm{stat}+\mathrm{sys})\ifmmode\times\else\texttimes\fi{}{10}^{6}\text{ }\text{ }{\mathrm{cm}}^{\ensuremath{-}2}\text{ }{\mathrm{s}}^{\ensuremath{-}1}$ by adding KamLAND results. In a three-flavor analysis combining all solar neutrino experiments, the upper limit of ${sin }^{2}{\ensuremath{\theta}}_{13}$ is 0.060 at 95% C.L.. After combination with KamLAND results, the upper limit of ${sin }^{2}{\ensuremath{\theta}}_{13}$ is found to be 0.059 at 95% C.L.
404 citations
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Duke University1, University of Tokyo2, University of California, Irvine3, Boston University4, University of Wisconsin-Madison5, Brookhaven National Laboratory6, California State University, Dominguez Hills7, Chonnam National University8, Gifu University9, Kanagawa University10, Kobe University11, Kyoto University12, Miyagi University of Education13, Nagoya University14, Stony Brook University15, Niigata University16, Okayama University17, Osaka University18, Seoul National University19, Shizuoka University20, Sungkyunkwan University21, Tokai University22, Tsinghua University23, University of Warsaw24, University of Washington25, University of Minnesota26
TL;DR: In this article, a search for nonzero {theta}{sub 13} and deviations of sin{sup 2{theta}}{sub 23} from 0.04(0.09) and 1.9(1.5) was conducted.
Abstract: We present a search for nonzero {theta}{sub 13} and deviations of sin{sup 2{theta}}{sub 23} from 0.5 in the oscillations of atmospheric neutrino data from Super-Kamiokande I, II, and III. No distortions of the neutrino flux consistent with nonzero {theta}{sub 13} are found and both neutrino mass hierarchy hypotheses are in agreement with the data. The data are best fit at {Delta}m{sup 2}=2.1x10{sup -3} eV{sup 2}, sin{sup 2{theta}}{sub 13}=0.0, and sin{sup 2{theta}}{sub 23}=0.5. In the normal (inverted) hierarchy {theta}{sub 13} and {Delta}m{sup 2} are constrained at the one-dimensional 90% C.L. to sin{sup 2{theta}}{sub 13}<0.04(0.09) and 1.9(1.7)x10{sup -3}<{Delta}m{sup 2}<2.6(2.7)x10{sup -3} eV{sup 2}. The atmospheric mixing angle is within 0.407{<=}sin{sup 2{theta}}{sub 23{<=}}0.583 at 90% C.L.
278 citations
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University of California, Irvine1, University of Tokyo2, Autonomous University of Madrid3, Boston University4, California State University, Dominguez Hills5, Chonnam National University6, Duke University7, Fukuoka Institute of Technology8, Gifu University9, Kobe University10, Kyoto University11, Miyagi University of Education12, Nagoya University13, Stony Brook University14, Okayama University15, Osaka University16, Seoul National University17, Shizuoka University18, Sungkyunkwan University19, Tokai University20, Tsinghua University21, University of Warsaw22, University of Washington23
TL;DR: A new Super-Kamiokande search for supernova relic neutrinos was conducted using 2853 live days of data as mentioned in this paper, and the results showed that the neutrino flux was between 2.8 and 3.3 MeV.
Abstract: A new Super-Kamiokande search for supernova relic neutrinos was conducted using 2853 live days of data. Sensitivity is now greatly improved compared to the 2003 Super-Kamiokande result, which placed a flux limit near many theoretical predictions. This more detailed analysis includes a variety of improvements such as increased efficiency, a lower energy threshold, and an expanded data set. New combined upper limits on supernova relic neutrino flux are between 2.8 and $3.1{\overline{\ensuremath{
u}}}_{e}\text{ }\text{ }{\mathrm{cm}}^{\ensuremath{-}2}\text{ }{\mathrm{s}}^{\ensuremath{-}1}g16\text{ }\text{ }\mathrm{MeV}$ total positron energy (17.3 MeV ${\mathrm{E}}_{\ensuremath{
u}}$).
203 citations
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TL;DR: This new version of micrOMEGAs is a major update which includes a generalization of the Boltzmann equations to accommodate models with asymmetric dark matter or with semi-annihilation and a first approach to a generalizations of the thermodynamics of the Universe in the relic density computation.
922 citations
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TL;DR: In this paper, a global analysis of the neutrino oscillation data available as of fall 2018 in the framework of three massive mixed neutrinos with the goal at determining the ranges of allowed values for the six relevant parameters.
Abstract: We present the results of a global analysis of the neutrino oscillation data available as of fall 2018 in the framework of three massive mixed neutrinos with the goal at determining the ranges of allowed values for the six relevant parameters. We describe the complementarity and quantify the tensions among the results of the different data samples contributing to the determination of each parameter. We also show how those vary when combining our global likelihood with the χ2 map provided by Super-Kamiokande for their atmospheric neutrino data analysis in the same framework. The best fit of the analysis is for the normal mass ordering with inverted ordering being disfavoured with a Δχ2 = 4.7 (9.3) without (with) SK-atm. We find a preference for the second octant of θ23, disfavouring the first octant with Δχ2 = 4.4 (6.0) without (with) SK-atm. The best fit for the complex phase is δCP = 215° with CP conservation being allowed at Δχ2 = 1.5 (1.8). As a byproduct we quantify the correlated ranges for the laboratory observables sensitive to the absolute neutrino mass scale in beta decay, $$ {m}_{
u_e} $$
, and neutrino-less double beta decay, mee, and the total mass of the neutrinos, Σ, which is most relevant in Cosmology.
860 citations
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TL;DR: This paper focuses on the PMNS mixing matrix and the latest global fits following the Daya Bay and RENO experiments which measure the reactor angle and gives a mini-review of finite group theory.
Abstract: This is a review paper about neutrino mass and mixing and flavour model building strategies based on discrete family symmetry. After a pedagogical introduction and overview of the whole of neutrino physics, we focus on the PMNS mixing matrix and the latest global fits following the Daya Bay and RENO experiments which measure the reactor angle. We then describe the simple bimaximal, tri-bimaximal and golden ratio patterns of lepton mixing and the deviations required for a non-zero reactor angle, with solar or atmospheric mixing sum rules resulting from charged lepton corrections or residual trimaximal mixing. The different types of see-saw mechanism are then reviewed as well as the sequential dominance mechanism. We then give a mini-review of finite group theory, which may be used as a discrete family symmetry broken by flavons either completely, or with different subgroups preserved in the neutrino and charged lepton sectors. These two approaches are then reviewed in detail in separate chapters including mechanisms for flavon vacuum alignment and different model building strategies that have been proposed to generate the reactor angle. We then briefly review grand unified theories (GUTs) and how they may be combined with discrete family symmetry to describe all quark and lepton masses and mixing. Finally, we discuss three model examples which combine an SU(5) GUT with the discrete family symmetries A₄, S₄ and Δ(96).
849 citations
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Perimeter Institute for Theoretical Physics1, Niigata University2, CERN3, University of Connecticut4, Leiden University5, Korea Astronomy and Space Science Institute6, Federico Santa María Technical University7, University of California, Santa Barbara8, University of Maryland, College Park9, Claude Bernard University Lyon 110, University of Lyon11, Northwestern University12, University of Victoria13, University of Manchester14, University of Bonn15, Technische Universität München16, École Polytechnique Fédérale de Lausanne17, Stony Brook University18, Autonomous University of Madrid19, University of Paris20, Centre national de la recherche scientifique21, Moscow Institute of Physics and Technology22, Autonomous University of Barcelona23, University of Copenhagen24, Université libre de Bruxelles25, University of La Serena26, University of Valencia27, Taras Shevchenko National University of Kyiv28, Heidelberg University29, Yonsei University30, Princeton University31, University of Geneva32, Harvard University33, Tomsk State University34, University of Tübingen35, Tomsk Polytechnic University36, University of Washington37, University of Florida38, University of Hamburg39, TRIUMF40, University of Iowa41, University of Grenoble42, International Centre for Theoretical Physics43, Hokkai Gakuen University44, University of Illinois at Urbana–Champaign45, Durham University46, University of Melbourne47, University of Naples Federico II48, York University49, University of California, Berkeley50, Lawrence Berkeley National Laboratory51
TL;DR: It is demonstrated that the SHiP experiment has a unique potential to discover new physics and can directly probe a number of solutions of beyond the standard model puzzles, such as neutrino masses, baryon asymmetry of the Universe, dark matter, and inflation.
Abstract: This paper describes the physics case for a new fixed target facility at CERN SPS. The SHiP (search for hidden particles) experiment is intended to hunt for new physics in the largely unexplored domain of very weakly interacting particles with masses below the Fermi scale, inaccessible to the LHC experiments, and to study tau neutrino physics. The same proton beam setup can be used later to look for decays of tau-leptons with lepton flavour number non-conservation, $\tau \to 3\mu $ and to search for weakly-interacting sub-GeV dark matter candidates. We discuss the evidence for physics beyond the standard model and describe interactions between new particles and four different portals—scalars, vectors, fermions or axion-like particles. We discuss motivations for different models, manifesting themselves via these interactions, and how they can be probed with the SHiP experiment and present several case studies. The prospects to search for relatively light SUSY and composite particles at SHiP are also discussed. We demonstrate that the SHiP experiment has a unique potential to discover new physics and can directly probe a number of solutions of beyond the standard model puzzles, such as neutrino masses, baryon asymmetry of the Universe, dark matter, and inflation.
842 citations
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TL;DR: The Jiangmen Underground Neutrino Observatory (JUNO) as mentioned in this paper is a 20kton multi-purpose underground liquid scintillator detector with the determination of neutrino mass hierarchy (MH) as a primary physics goal.
Abstract: The Jiangmen Underground Neutrino Observatory (JUNO), a 20 kton multi-purpose underground liquid scintillator detector, was proposed with the determination of the neutrino mass hierarchy (MH) as a primary physics goal. The excellent energy resolution and the large fiducial volume anticipated for the JUNO detector offer exciting opportunities for addressing many important topics in neutrino and astro-particle physics. In this document, we present the physics motivations and the anticipated performance of the JUNO detector for various proposed measurements. Following an introduction summarizing the current status and open issues in neutrino physics, we discuss how the detection of antineutrinos generated by a cluster of nuclear power plants allows the determination of the neutrino MH at a 3–4σ significance with six years of running of JUNO. The measurement of antineutrino spectrum with excellent energy resolution will also lead to the precise determination of the neutrino oscillation parameters ${\mathrm{sin}}^{2}{\theta }_{12}$, ${\rm{\Delta }}{m}_{21}^{2}$, and $| {\rm{\Delta }}{m}_{{ee}}^{2}| $ to an accuracy of better than 1%, which will play a crucial role in the future unitarity test of the MNSP matrix. The JUNO detector is capable of observing not only antineutrinos from the power plants, but also neutrinos/antineutrinos from terrestrial and extra-terrestrial sources, including supernova burst neutrinos, diffuse supernova neutrino background, geoneutrinos, atmospheric neutrinos, and solar neutrinos. As a result of JUNO's large size, excellent energy resolution, and vertex reconstruction capability, interesting new data on these topics can be collected. For example, a neutrino burst from a typical core-collapse supernova at a distance of 10 kpc would lead to ∼5000 inverse-beta-decay events and ∼2000 all-flavor neutrino–proton ES events in JUNO, which are of crucial importance for understanding the mechanism of supernova explosion and for exploring novel phenomena such as collective neutrino oscillations. Detection of neutrinos from all past core-collapse supernova explosions in the visible universe with JUNO would further provide valuable information on the cosmic star-formation rate and the average core-collapse neutrino energy spectrum. Antineutrinos originating from the radioactive decay of uranium and thorium in the Earth can be detected in JUNO with a rate of ∼400 events per year, significantly improving the statistics of existing geoneutrino event samples. Atmospheric neutrino events collected in JUNO can provide independent inputs for determining the MH and the octant of the ${\theta }_{23}$ mixing angle. Detection of the (7)Be and (8)B solar neutrino events at JUNO would shed new light on the solar metallicity problem and examine the transition region between the vacuum and matter dominated neutrino oscillations. Regarding light sterile neutrino topics, sterile neutrinos with ${10}^{-5}\,{{\rm{eV}}}^{2}\lt {\rm{\Delta }}{m}_{41}^{2}\lt {10}^{-2}\,{{\rm{eV}}}^{2}$ and a sufficiently large mixing angle ${\theta }_{14}$ could be identified through a precise measurement of the reactor antineutrino energy spectrum. Meanwhile, JUNO can also provide us excellent opportunities to test the eV-scale sterile neutrino hypothesis, using either the radioactive neutrino sources or a cyclotron-produced neutrino beam. The JUNO detector is also sensitive to several other beyondthe-standard-model physics. Examples include the search for proton decay via the $p\to {K}^{+}+\bar{
u }$ decay channel, search for neutrinos resulting from dark-matter annihilation in the Sun, search for violation of Lorentz invariance via the sidereal modulation of the reactor neutrino event rate, and search for the effects of non-standard interactions. The proposed construction of the JUNO detector will provide a unique facility to address many outstanding crucial questions in particle and astrophysics in a timely and cost-effective fashion. It holds the great potential for further advancing our quest to understanding the fundamental properties of neutrinos, one of the building blocks of our Universe.
807 citations