Study of K meson decay amplitudes from the lattice QCD

• Project/Area Number: 23340054
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Particle/Nuclear/Cosmic ray/Astro physics
• Research Institution: University of Tsukuba
• Principal Investigator: ISHIZUKA Naruhito 筑波大学, 数理物質系, 准教授 (70251030)
• Co-Investigator(Kenkyū-buntansha): UKAWA Akira 筑波大学, 数理物質系, 教授 (10143538) ; YOSHIE Tomoteru 筑波大学, 数理物質系, 准教授 (40183991)
• Co-Investigator(Renkei-kenkyūsha): ISHIKAWA Kennichi 広島大学, 理学研究科, 准教授 (60334041)
• Project Period (FY): 2011-04-01 – 2014-03-31
• Project Status: Completed (Fiscal Year 2013)
• Budget Amount: ¥13,390,000 (Direct Cost: ¥10,300,000、Indirect Cost: ¥3,090,000); Fiscal Year 2013: ¥3,770,000 (Direct Cost: ¥2,900,000、Indirect Cost: ¥870,000); Fiscal Year 2012: ¥4,290,000 (Direct Cost: ¥3,300,000、Indirect Cost: ¥990,000); Fiscal Year 2011: ¥5,330,000 (Direct Cost: ¥4,100,000、Indirect Cost: ¥1,230,000)
• Keywords: 格子場の理論 / 素粒子標準模型 / K中間子崩壊振幅 / ΔI=1/2則 / CP非保存パラメータ / 格子QCD / K中間子崩壤振幅 / U(1)問題

Research Abstract

An aim of this project is a study of the Delta I=1/2 rule in the neutral K meson system and a calculation of the CP violation parameter from the Standard model of the particle physics by a lattice calculation of the K meson decay amplitudes. We consider the K meson decay process to the zero momentum two pion. Our calculations are carried out at the pion mass 280 MeV. We found that our methods are efficient for a calculation of the decay amplitudes Re(A0) and Re(A2). Our result is Re(A0)/Re(A2)=24.7(14.7) and the enhancement of Delta I=1/2 process is shown. From this, understanding of the Delta I=1/2 rule by calculations with our method at near physical point is expected in the future.

Research Products

• [Journal Article] Calculation of K->ππ decay amplitudes with improved Wilson fermion (2013)
  • Author(s): N. Ishizuka, K. I. Ishikawa, A. Ukawa, T. Yoshie
  • Journal Title: Proceeding of Science (LATTICE 2013) Volume: 474(1-7)
  • URL: http://pos.sissa.it/cgi-bin/reader/conf.cgi?confid=187
  • Peer Reviewed
• [Journal Article] Calculation of K→ππ decay amplitudes with improved Wilson fermion (2013)
  • Author(s): N.Ishizuka, K.I. Ishikawa, A. Ukawa, T. Yoshie
  • Journal Title: Proceedings of Science Volume: PoS(LATTICE 2013)
  • Peer Reviewed
• [Presentation] Calculation of K→ππ decay amplitudes with improved Wilson fermion (2013)
  • Author(s): Naruhito Ishizuka
  • Organizer: 31st International Symposium on Lattice Field Theory
  • Place of Presentation: Mainz, Germany