コニシ ヤスフミ小西 康文准教授Yasufumi KONISHI
■研究者基本情報
経歴
■研究活動情報
論文
- Mind the Gap on IceCube: Cosmic neutrino spectrum and muon anomalous magnetic moment
T.Araki; F.Kaneko; Y.Konishi; T.Ota; J.Sato; T.Shimomura
eprint arXiv:1505.01284, 2015年05月06日, ［査読有り］ - Cosmic neutrino spectrum and the muon anomalous magnetic moment in the gauged Lμ−Lτmodel
Takeshi Araki; Fumihiro Kaneko; Yasufumi Konishi; Toshihiko Ota; Joe Sato; Takashi Shimomura, The energy spectrum of cosmic neutrinos, which was recently reported by the IceCube Collaboration, shows a gap between 400 TeV and 1 PeV. An unknown neutrino interaction mediated by a field with a mass of the MeV scale is one of the possible solutions to this gap. We examine whether the leptonic gauge interaction L-mu - L-tau can simultaneously explain the two phenomena in the lepton sector: the gap in the cosmic neutrino spectrum and the unsettled disagreement in the muon anomalous magnetic moment. We illustrate that there remain regions in the model parameter space which account for both of the problems. Our results also provide a hint to the distance to the source of the high-energy cosmic neutrinos., AMER PHYSICAL SOC
Physical Review D, 2015年02月02日 - Big-bang nucleosynthesis through bound-state effects with a long-lived slepton in the NMSSM
Kazunori Kohri; Masafumi Koike; Yasufumi Konishi; Shingo Ohta; Joe Sato; Takashi Shimomura; Kenichi Sugai; and Masato Yamanaka, We show that the Li problems can be solved in the next-to-minimal supersymmetric standard model where the slepton as the next-to-lightest supersymmetric (SUSY) particle is very long lived. Such a long-lived slepton induces exotic nuclear reactions in big-bang nucleosynthesis, and destroys and produces the Li-7 and Li-6 nuclei via bound state formation. We study cases where the lightest SUSY particle is singlino-like neutralino and bino-like neutralino to present allowed regions in the parameter space, which is consistent with the observations on the dark matter and the Higgs mass., AMER PHYSICAL SOC
Physical Review D, 2014年08月06日 - First evidence of the constrained minimal supersymmetric standard model is appearing soon
Yasufumi Konishi; Shingo Ohta; Joe Sato; Takashi Shimomura; Kenichi Sugai; and Masato Yamanaka, We explore the coannihilation region of the constrained minimal supersymmetric standard model (CMSSM) being consistent with current experimental/observational results. The requirements from the experimental/observational results are the 125 GeV Higgs boson mass and the relic abundances of both the dark matter and light elements, especially lithium-7. We put these requirements on the calculated values, and, thus, we obtain the allowed region. Then we give predictions to the mass spectra of the supersymmetric (SUSY) particles, the anomalous magnetic moment of the muon, the branching fractions of the B-meson rare decays, the direct detection of the neutralino dark matter, and the number of SUSY particles produced in a 14 TeV run at the LHC experiment. Comparing these predictions with current bounds, we show the feasibility of the test for this scenario in near future experiments., AMER PHYSICAL SOC
Physical Review D, 2014年04月08日 - Minimal dilaton model
Tomohiro Abe; Ryuichiro Kitano; Yasufumi Konishi; Kin-ya Oda; Joe Sato; and Shohei Sugiyama, Both the ATLAS and CMS experiments at the LHC have reported the observation of the particle of mass around 125 GeV which is consistent to the Standard Model (SM) Higgs boson, but with an excess of events beyond the SM expectation in the diphoton decay channel at each of them. There still remains room for a logical possibility that we are not seeing the SM Higgs but something else. Here we introduce the minimal dilaton model in which the LHC signals are explained by an extra singlet scalar of the mass around 125 GeV that slightly mixes with the SM Higgs heavier than 600 GeV. When this scalar has a vacuum expectation value well beyond the electroweak scale, it can be identified as a linearly realized version of a dilaton field. Though the current experimental constraints from the Higgs search disfavors such a region, the singlet scalar model itself still provides a viable alternative to the SM Higgs in interpreting its search results. © Owned by the authors, published by EDP Sciences, 2013.
EPJ Web of Conferences, 2013年 - Minimal dilaton model
Tomohiro Abe; Ryuichiro Kitano; Yasufumi Konishi; Kin-ya Oda; Joe Sato; and Shohei Sugiyama, We construct a minimal calculable model of a light dilaton based on the scenario where only top and Higgs sectors are involved in a quasiconformal dynamics. The model consistently accommodates the electroweak precision tests even when the Higgs boson is very heavy, thereby allowing one to consider the possibility that the particle at around 125 GeV, discovered at the LHC experiments, is identified as the light dilaton rather than the Higgs boson. We find that the current LHC data allow distinct parameter regions where the observed particle is either mostly the Higgs boson or the dilaton., AMER PHYSICAL SOC
Physical Review D, 2012年12月07日 - Effect of non-standard interaction for radiative neutrino mass model
Yasufumi Konishi; Joe Sato; and Takashi Shimomura, We examined effects of non-standard interactions (NSIs) in a radiative neutrino mass model. The radiative neutrino mass model suggested by Kraus Nasri and Trodden can explain not only neutrino flavor mixing and neutrino masses, but also dark matter relic abundance. Although the NSI effects of the model are too small to be detected by present neutrino oscillation experiments, we might observe the small effects in future experiments such as neutrino factory., AMER INST PHYSICS
AIP Conference Proceedings, 2012年07月25日 - Constraints from Unrealistic Vacua in the Next-to-Minimal Supersymmetric Standard Model(Particles and Fields)
KANEHATA Yoshimi; KOBAYASHI Tatsuo; KONISHI Yasufumi; Osamu SETO; Takashi SHIMOMURA; Maskawa Institute for Science and Culture Kyoto Sangyo University:Department of Physics Ochanomizu University; Department of Physics Kyoto University; Maskawa Institute for Science and Culture Kyoto Sangyo University; Department of Architecture and Building Engineering Hokkai-Gakuen University; Yukawa Institute for Theoretical Physics Kyoto University, We study constraints to avoid deep unrealistic minima in the next-to-minimal supersymmetric standard model. We analyze the scalar potential along directions where all of and one of the three Higgs fields develop their vacuum expectation values, and find unrealistic minima deeper than the electroweak symmetry breaking (EWSB) vacuum. These unrealistic minima threaten the realization of successful EWSB and therefore should be avoided. Necessary conditions for avoiding these minima result in constraints on parameters. We show that a wide and significant region of the parameter space, especially a large λ, is ruled out by our constraints., Publication Office, Progress of Theoretical Physics
Progress of theoretical physics, 2011年12月25日 - Constraints from unrealistic vacua in the supersymmetric standard model with neutrino mass operators
Yoshimi Kanehata; Tatsuo Kobayashi; Yasufumi Konishi; and Takashi Shimomura, We analyze a scalar potential of the minimal supersymmetric standard model (MSSM) with neutrino mass operators along unbounded-from-below and color and/or charged breaking directions. We show necessary conditions to avoid the potential minima which can be deeper than the realistic vacuum. These conditions would constrain more strongly than conditions in the MSSM without taking into account neutrino mass operators and can improve the predictive power of supersymmetric models with neutrino mass operators., AMER PHYSICAL SOC
Physical Review D, 2010年10月27日 - Dirac Mass Matrices in Gauge Field Theory of Horizontal Symmetry(Particles and Fields)
Konishi Yasufumi; Sogami Ikuo S.; Physics Department Kyoto Sangyo University; Physics Department Kyoto Sangyo University, We investigate Dirac mass matrices derived in the gauge field theory of a horizontal symmetry generated by a central extension of the Pauli algebra. Through numerical analyses of the observed data of the charged fermion masses and the flavor mixing matrix of quarks, values of free parameters in the mass matrices are determined and several empirical relations are found among the Yukawa coupling constants., Publication Office, Progress of Theoretical Physics
Progress of theoretical physics, 2010年02月25日 - Notes on Flavor Mixing Matrices Characterized by SU(2)×U(1) Group Parameters
Sogami Ikuo S; Konishi Yasufumi; Physics Department. Kyoto; Sangyo University; Physics Department. Kyoto; Sangyo University, A flavor mixing matrix (FMM) characterized uniquely by four group parameters of the SU(2)×U(1) symmetry is applied to the investigation of experimental results for the lepton and quark sectors. Neutrino oscillation data are analyzed by assuming that the 1-3 component of the lepton FMM vanishes. With this assumption, the lepton FMM is expressed in terms of analytic functions depending effectively on two group parameters. It is confirmed that, while all group parameters of the lepton FMM have values of approximately the same order of magnitude, those of the quark FMM have very different values with hierarchical structures. We make a conjecture concerning the behavior of the lepton FMM with a small but non-vanishing 1-3 component., Published for the Yukawa Institute for Theoretical Physics and the Physical Society of Japan
Progress of theoretical physics, 2008年02月
MISC
- 高等学校情報科目用教科書に基づく教育の内容の分類
小西 康文
茨城大学全学教育機構論集 大学教育研究, 2024年03月, ［査読有り］ - 令和の日本型学校教育についての研究
東京懇談会 研究紀要, 2023年11月30日 - TOEICの結果から考察するコロナ禍の学生の英語学修状況
小西 康文・上田 敦子・大津 理香・大森 真・大山 簾・菊池 武・小林 邦彦・佐々木 友美・館 深雪
茨城大学全学教育機構論集 大学教育研究, 2023年03月, ［査読有り］ - 学習管理システムに蓄積されたアクセスログの解析
小西 康文
茨城大学全学教育機構論集 大学教育研究, 2022年03月 - コロナ禍における学びの保障
東京懇談会 研究紀要, 2021年08月30日 - 微分積分のオンライン授業に対するアンケート調査
小西 康文
茨城大学全学教育機構論集 大学教育研究, 2021年03月 - 教育現場が直面している諸課題についての研究
東京懇談会 研究紀要, 2020年11月30日 - 2018 年度 TOEIC スコアと授業アンケートの関係
茨城大学全学教育機構論集, 2020年03月 - 小学校・中学校理科の学習内容に関する分析
小西 康文
東京懇談会 研究紀要, 2019年11月30日 - 電子機器を活用した有効な数学教育への準備
小西 康文
茨城大学全学教育機構論集, 2018年03月01日 - TOEICテストスコアとアンケート分析による茨城大学総合英語プログラム改善のための因子分析
小林 邦彦・小西 康文・福田 浩子・佐々木 友美・上田 敦子・大森 真・館 深雪・野村 幸代・藤井 拓哉
茨城大学 大学教育センター紀要, 2016年06月01日
講演・口頭発表等
- Radiative 模型における NSI と 0ν2β
小西康文
3rd Workshop on Next Generation Accelerator-based Neutrino Experiment, 2014年06月22日 - Effect of Non-standard interaction for radiative neutrino mass model
Yasufumi Konishi
Basis of the Universe with Revolutionary Ideas 2014, 2014年02月14日 - Non-standard interactions in radiative seesaw mechanism of neutrino mass
Yasufumi Konishi
PASCOS 2013, 2013年11月24日 - Effect of non-standard interaction for a radiative neutrino mass model
Yasufumi Konishi
Summer Institute 2012, 2012年08月22日 - ニュートリノ質量の輻射生成模型における非標準的相互作用の効果
小西康文
日本物理学会2012年春, 2012年03月24日 - Effect of non-standard interaction for radiative neutrino mass model
Yasufumi Konishi
GUT 2012, 2012年03月15日 - NMSSM のスカラーポテンシャルにおけるパラメータ間の制限
小西康文
日本物理学会2011年秋, 2011年09月16日 - Constraints from Unrealistic Vacua in the NMSSM
Yasufumi Konishi
Summer Institute 2011, 2011年08月13日 - Constraints from unrealistic Vacua in the NMSSM
小西康文
日本物理学会 2011 年春, 2011年03月 - Constraints from unrealistic Vacua in the NMSSM
小西康文
日本物理学会 2011 年春, 2011年03月 - General Dirac Mass Matrices in Gauge theory of Horizontal Symmetry Generated by a Central Extension of the Pauli Algebra
Yasufumi Konishi
Flavor physics in the LHC e, 2010年11月 - Constraints from Unrealistic Vacua in Supersymmetric Standard Model with Neutrino Mass Operators
小西康文
B workshop 2010, 2010年10月 - 水平対称性のゲージ場理論におけるディラック型の質量行列
小西康文
日本物理学会 2010 年秋, 2010年09月
