ヒッグス粒子発見後の素粒子物理学の新展開～LHCによる真空と時空構造の解明～

• Project Area: New expansion of particle physics of post-Higgs era by LHC revealing the vacuum and space-time structure
• Project/Area Number: 16K21730
• Research Category: Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area)
• Allocation Type: Multi-year Fund
• Review Section: Science and Engineering
• Research Institution: The University of Tokyo
• Principal Investigator: 浅井 祥仁 東京大学, 大学院理学系研究科(理学部), 教授 (60282505)
• Project Period (FY): 2016-06-30 – 2023-03-31
• Project Status: Granted (Fiscal Year 2021)
• Budget Amount: ¥52,650,000 (Direct Cost: ¥40,500,000、Indirect Cost: ¥12,150,000); Fiscal Year 2020: ¥10,530,000 (Direct Cost: ¥8,100,000、Indirect Cost: ¥2,430,000); Fiscal Year 2019: ¥10,530,000 (Direct Cost: ¥8,100,000、Indirect Cost: ¥2,430,000); Fiscal Year 2018: ¥10,530,000 (Direct Cost: ¥8,100,000、Indirect Cost: ¥2,430,000); Fiscal Year 2017: ¥10,530,000 (Direct Cost: ¥8,100,000、Indirect Cost: ¥2,430,000); Fiscal Year 2016: ¥10,530,000 (Direct Cost: ¥8,100,000、Indirect Cost: ¥2,430,000)
• Keywords: 素粒子実験 / 素粒子論 / 加速器

Outline of Annual Research Achievements

LHCの第２期実験の全データを解析し、「世代の解明」、「質量の起源の解明」、「新しい真空の発見（新現象の示唆）」などの多くの成果が得られた。物質を形作る素粒子（フェルミ粒子）、力を伝える素粒子（z、w）は、全く別々の機構ではあるが、発見されたヒッグス場がその源になっていることがわかった。このヒッグス場との結合の強さが O(1)からO(10^-5)と大きく変化することによりさまざまな素粒子の質量や世代が創造されていることが判明した。なぜ、こんなに小さな定数になるのか、新しい真空状態が関係する新現象は何か？を国際活動支援班が中心となって、領域外の海外研究者と進めてきてきたが、新型コロナ感染症による移動の制限で、海外との研究とは実際の往復でなく、オンラインになってしまい、支出が生じなかった。また、ヒッグス場が不安定であり新しい素粒子現象の存在が不可欠であることがわかり、宇宙初期の重力波研究などにより探ることができると領域研究でわかった。これをどう観測に結びつけるかを国際活動支援班と総括班が中心となって進める準備を行っていた。
国際活動支援班は令和3年度は、成果をまとめた国際会議を開催する予定で準備を行ってきたが、コロナの影響で令和4年度へ会議を延期した。

Current Status of Research Progress

3: Progress in research has been slightly delayed.

Reason

新型コロナウィルス感染症のために、研究者が往来できなくなり、これにともない、本領域が企画していた大型国際会議、招聘、がキャンセルになっている。 オンラインで行える物理解析研究は、他分野の技術を積極的に取り入れ研究を進めた。
１）機械学習を用いて、ボトムクォークとヒッグス粒子の結合の強さ を世界で初めて観測し、力を伝える素粒子ばかりでなく、物質を形作る素粒子の質量の起源も、同じヒッグス粒子であることを示した。
２）ヒッグス粒子を詳細 に調べることで、我々の真空が、一番安定な状態ではなく、少しエネルギーが高く不安定であることが判明するなどの重要な成果である。
この成果を領域の内外に発信する国際研究会を令和2年度に準備していたが、新型コロナ感染症に伴い、外国人研究者の入国が難しく、延期を繰り返し、令和4年に開催することになった。
一方、第3期実験を令和2年度末に行う予定で準備を進めてきたが、研究所が閉鎖されたり、研究者が集まれなくなったために準備が遅れてしまっており、令和4年度初めに実験開始に遅れになってしまった。大型国際計画は、国境なき研究者の移動が基本となっており、新型コロナ感染症の影響は大きかった。

Strategy for Future Research Activity

二つの研究課題を令和4年度に推進する。1つ目として若手研究者の海外研究機関への長期滞在を行い、LHCの第3期実験を開始する。第3期実験は、エネルギーが増強され、検出器が改良されるなど、大きなアップグレードがなされている。現地に研究者を送りスムーズな実験の立ち上がりに貢献する。オンラインによる国内の滞在者が協力して行える体制もいかしながら、現地の研究者と力を合わせて進めていく。2つ目として令和4年5月12日より、国際会議　「Physics in LHC and Beyond」を松江で開催する。(https://indico.cern.ch/event/1102363/)　海外からの研究者も参加（一部はオンラインのハイブリッド）して、本領域の成果をとりまとめる。

Research Products

• [Int'l Joint Research] INFN Roma-I/INFN Pisa/University of Florence(イタリア)
• [Int'l Joint Research] CERN(スイス)
• [Int'l Joint Research] SLAC/Boston University/University of Michigan(米国)
• [Int'l Joint Research] Max-Plank Institute(ドイツ)
• [Int'l Joint Research] Durham University/University of Cambridge(英国)
• [Int'l Joint Research]
• [Int'l Joint Research] INFN Roma-I/INFN Pisa/University of Florence(イタリア)
• [Int'l Joint Research] CERN(スイス)
• [Int'l Joint Research] SLAC/Boston University/University of Michigan(米国)
• [Int'l Joint Research] Max-Plank Institute(ドイツ)
• [Int'l Joint Research] Durham University/University of Cambridge(英国)
• [Int'l Joint Research]
• [Int'l Joint Research] INFN Roma-I/INFN Pisa/University of Florence(イタリア)
• [Int'l Joint Research] CERN(スイス)
• [Int'l Joint Research] SLAC/Boston University/University of Michigan(米国)
• [Int'l Joint Research] Max-Plank Institute(ドイツ)
• [Int'l Joint Research] Durham University/University of Cambridge(英国)
• [Int'l Joint Research]
• [Int'l Joint Research] INFN Roma-I/INFN Pisa/University of Florence(イタリア)
• [Int'l Joint Research] CERN(スイス)
• [Int'l Joint Research] SLAC/Boston University/University of Michigan(米国)
• [Int'l Joint Research] Max-Planck Institute(ドイツ)
• [Int'l Joint Research] Durham University/University of Cambridge(英国)
• [Int'l Joint Research]
• [Int'l Joint Research] INFN Roma-I/INFN-Pisa/University of Florence(イタリア)
• [Int'l Joint Research] CERN(スイス)
• [Int'l Joint Research] SLAC/Boston University/University of Michigan(米国)
• [Int'l Joint Research] Max-Planck Institute(ドイツ)
• [Int'l Joint Research] Durham University/University of Cambridge(英国)
• [Int'l Joint Research]
• [Journal Article] Proton decay in SUSY GUTs (2022)
  • Author(s): Hisano Junji
  • Journal Title: Progress of Theoretical and Experimental Physics Volume: ptac017 Issue: 12 Pages: 1-15
  • DOI: 10.1093/ptep/ptac017
  • Peer Reviewed / Open Access
• [Journal Article] Gamma-ray line from electroweakly interacting non-abelian spin-1 dark matter (2021)
  • Author(s): Abe Tomohiro、Fujiwara Motoko、Hisano Junji、Matsushita Kohei
  • Journal Title: Journal of High Energy Physics Volume: 2021 Issue: 10 Pages: 163-163
  • DOI: 10.1007/jhep10(2021)163
  • Peer Reviewed / Open Access
• [Journal Article] Vanishing or non-vanishing rainbow? Reduction formulas of electric dipole moment (2021)
  • Author(s): Fujiwara Motoko、Hisano Junji、Toma Takashi
  • Journal Title: Journal of High Energy Physics Volume: 2021 Issue: 10 Pages: 237-237
  • DOI: 10.1007/jhep10(2021)237
  • Peer Reviewed / Open Access
• [Journal Article] Electric dipole moments in the extended scotogenic models (2021)
  • Author(s): Motoko Fujiwara, Junji Hisano, Chihiro Kanai, Takashi Toma
  • Journal Title: JHEP Volume: 04 Issue: 4 Pages: 114-114
  • DOI: 10.1007/jhep04(2021)114
  • Peer Reviewed / Open Access
• [Journal Article] A search for the dimuon decay of the Standard Model Higgs boson with the ATLAS detector (2021)
  • Author(s): ATLAS Collaboration
  • Journal Title: Physics Letters B Volume: 812 Pages: 135980-135980
  • DOI: 10.1016/j.physletb.2020.135980
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] A search for the Zγ decay mode of the Higgs boson in pp collisions at √s=13 TeV with the ATLAS detector (2020)
  • Author(s): ATLAS Collaboration
  • Journal Title: Physics Letters B Volume: 809 Pages: 135754-135754
  • DOI: 10.1016/j.physletb.2020.135754
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Evidence for tt tt production in the multilepton final state in proton-proton collisions at √s=13 TeV with the ATLAS detector (2020)
  • Author(s): ATLAS Collaboration
  • Journal Title: The European Physical Journal C Volume: 80 Issue: 11 Pages: 1085-1085
  • DOI: 10.1140/epjc/s10052-020-08509-3
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Studying gaugino masses in supersymmetric model at future 100 TeV pp collider (2019)
  • Author(s): Asai Shoji、Chigusa So、Kaji Toshiaki、Moroi Takeo、Saito Masahiko、Sawada Ryu、Tanaka Junichi、Terashi Koji、Uno Kenta
  • Journal Title: Journal of High Energy Physics Volume: 2019 Issue: 5 Pages: 179-179
  • DOI: 10.1007/jhep05(2019)179
  • Peer Reviewed / Open Access
• [Journal Article] Discovery reach for wino and higgsino dark matter with a disappearing track signature at a 100 TeV pp collider (2019)
  • Author(s): Saito Masahiko、Sawada Ryu、Terashi Koji、Asai Shoji
  • Journal Title: The European Physical Journal C Volume: 79 Issue: 6 Pages: 469-469
  • DOI: 10.1140/epjc/s10052-019-6974-2
  • Peer Reviewed / Open Access
• [Journal Article] FCC-hh: The Hadron Collider (2019)
  • Author(s): A. Abada, S. Asai, J. Tanaka et al
  • Journal Title: The European Physical Journal Special Topics Volume: 228 Issue: 4 Pages: 775-1107
  • DOI: 10.1140/epjst/e2019-900087-0
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Review of Particle Physics (2018)
  • Author(s): Tanabashi M.、Hagiwara K.、Hikasa K.、Nakamura K.、Murayama H.、et al.
  • Journal Title: Physical Review D Volume: 98 Issue: 3 Pages: 030001-030001
  • DOI: 10.1103/physrevd.98.030001
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Search for long-lived, massive particles in events with displaced vertices and missing transverse momentum in sqrt(s) = 13 TeV pp collisions with the ATLAS detector (2018)
  • Author(s): M. Aaboud, K. Hanagaki, J. Tojo, F. Ukegawa, et al. [ATLAS Collaboration]
  • Journal Title: Phys. Rev. D Volume: 97 Issue: 5 Pages: 52012-52012
  • DOI: 10.1103/physrevd.97.052012
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Evidence for the associated production of the Higgs boson and a top quark pair with the ATLAS detector (2018)
  • Author(s): ATLAS Collaboration
  • Journal Title: Physical Review D Volume: 97 Issue: 7 Pages: 072003-072003
  • DOI: 10.1103/physrevd.97.072003
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Search for W W/W Z resonance production in lvqq final states in pp collisions at √s = 13 TeV with the ATLAS detector (2018)
  • Author(s): The ATLAS collaboration (M. Aaboud, M. Ishino, H. Nanjo, T. Sumida, K. Yorita et al.)
  • Journal Title: Journal of High Energy Physics Volume: 3 Issue: 3 Pages: 42-42
  • DOI: 10.1007/jhep03(2018)042
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Model independent evaluation of the Wilson coefficient of the Weinberg operator in QCD (2018)
  • Author(s): T. Abe, J. Hisano and R. Nagai
  • Journal Title: Journal of High Energy Physics Volume: 3 Pages: 175-175
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Search for new phenomena with large jet multiplicities and missing transverse momentum using large-radius jets and flavour-tagging at ATLAS in 13 TeV pp collisions (2017)
  • Author(s): T.Saito et al., ATLAS Collaboration
  • Journal Title: Journal of High Energy Physics Volume: 12 Issue: 12 Pages: 1-50
  • DOI: 10.1007/jhep12(2017)034
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Evidence for the H→bb decay with the ATLAS detector (2017)
  • Author(s): Aaboud M. et. al. (The ATLAS collaboration)
  • Journal Title: Journal of High Energy Physics Volume: 2017 Issue: 12 Pages: 024-092
  • DOI: 10.1007/jhep12(2017)024
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Subnanosecond time-to-digital converter implemented in a Kintex-7 FPGA (2017)
  • Author(s): Sano Y.、Horii Y.、Ikeno M.、Sasaki O.、Tomoto M.、Uchida T.
  • Journal Title: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment Volume: 874 Pages: 50-56
  • DOI: 10.1016/j.nima.2017.08.038
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Dark matter physics, flavor physics and LHC constraints in the dark matter model with a bottom partner (2017)
  • Author(s): T.Abe, J.Kawamura, S.Okawa, Y.Omura
  • Journal Title: Journal of High Energy Physics Volume: - Issue: 3 Pages: 042-042
  • DOI: 10.1007/jhep03(2017)058
  • Peer Reviewed / Open Access / Acknowledgement Compliant
• [Presentation] Recent progress on jet structure for BSM (2021)
  • Author(s): 野尻 美保子
  • Organizer: SUSY 2021
  • Int'l Joint Research / Invited
• [Presentation] Electroweak-Interacting dark matter -Window to BSM@TeV- (2021)
  • Author(s): 久野 純治
  • Organizer: Workshop "Quarkonia meet Dark Matter”
  • Int'l Joint Research / Invited
• [Presentation] Electroweakly Interacting Dark Matter (2021)
  • Author(s): 久野 純治
  • Organizer: KASHIWA DARK MATTER SYMPOSIUM 2021
  • Int'l Joint Research / Invited
• [Presentation] Search for Leptoquarks using the ATLAS detector (2020)
  • Author(s): Yasuyuki Okumura
  • Organizer: ICHEP202
  • Int'l Joint Research
• [Presentation] Observations of weak boson scattering with the ATLAS detector (2020)
  • Author(s): Takuya Nobe
  • Organizer: ICHEP2020
  • Int'l Joint Research
• [Presentation] 「素粒子物理実験」とAIの接点 (2019)
  • Author(s): 田中純一
  • Organizer: JSAI2019
  • Invited
• [Presentation] Search for additional neutral Higgs bosons in the MSSM (2018)
  • Author(s): J. Tanaka
  • Organizer: ICHEP2018
  • Int'l Joint Research
• [Presentation] Status and highlights from the ATLAS experiment (2018)
  • Author(s): K. Nagano
  • Organizer: LHCP2018
  • Int'l Joint Research / Invited
• [Presentation] Single Event Upsets in the ATLAS IBL Frontend ASICs (2018)
  • Author(s): Y. Takubo
  • Organizer: Pixel2018
  • Int'l Joint Research
• [Presentation] Study of efficiency and noise of fine pitch planar pixel detector for ATLAS ITk upgrade (2018)
  • Author(s): K. Nakamura
  • Organizer: Pixel2018
  • Int'l Joint Research
• [Presentation] Searches for new physics in final states with top quarks with ATLAS (2018)
  • Author(s): M. Aoki
  • Organizer: LHCP2018
  • Int'l Joint Research
• [Presentation] ATLAS Detector Performance in Run2 and Upgrade Plans (2017)
  • Author(s): Masaya Ishino (for ATLAS collaboration)
  • Organizer: High-Energy Physics International Conference in Quantum Chromodynamics
  • Int'l Joint Research
• [Presentation] Mono-jet searches (2017)
  • Author(s): Osamu Jinnouchi (for ATLAS and CMS collaborations)
  • Organizer: DM @ LHC 2017
  • Int'l Joint Research
• [Presentation] Baryon-number violating nucleon decay - Review from theoretical (2017)
  • Author(s): Junji Hisano
  • Organizer: NNN17
  • Int'l Joint Research
• [Presentation] Searches for Beyond SM Higgs bosons (2017)
  • Author(s): Soshi Tsuno
  • Organizer: The 28th International Symposium on Lepton Photon Interactions at High Energies
  • Int'l Joint Research
• [Presentation] The alignment limit in two Higgs doublet models (2017)
  • Author(s): Sabine Kraml
  • Organizer: HPNP2017
  • Place of Presentation: 富山大学（富山県富山市）
  • Int'l Joint Research / Invited
• [Presentation] Flavor physics induced by light Z′ from SO(10) GUT. (2016)
  • Author(s): Y. Omura
  • Organizer: B2Tips workshop
  • Place of Presentation: Munich (Germany)
  • Year and Date: 2016-11-15
  • Int'l Joint Research
• [Presentation] Exploring neutrino mass generation mechanisms via the lepton flavor violating decay of the Higgs boson (2016)
  • Author(s): H. Sugiyama
  • Organizer: DISCRETE2016
  • Place of Presentation: Warszawa (Poland)
  • Int'l Joint Research
• [Presentation] Neutrinos at LHC (2016)
  • Author(s): T. Sumida
  • Organizer: LHC Days 2016
  • Place of Presentation: Split (Croatia)
  • Int'l Joint Research / Invited
• [Funded Workshop] 新テラスケール研究会 (2019)
• [Funded Workshop] HNPN2019 (2019)
• [Funded Workshop] DIS2018 (2018)
• [Funded Workshop] ATLAS Overview Week (2018)
• [Funded Workshop] HC2018 (2018)
• [Funded Workshop] LAr Week March 2018 in Tokyo (2018)
• [Funded Workshop] ATLAS CERN-Tokyo 2017 Winter/Spring Workshop (2017)
  • Place of Presentation: 東京大学（東京都文京区）
  • Year and Date: 2017-03-23
• [Funded Workshop] Physics in LHC and the Early Universe (2017)
  • Place of Presentation: 東京大学（東京都文京区）
  • Year and Date: 2017-01-09