ｅｔａ’原子核にみる有限密度でのカイラル対称性回復とＵＡ（１）量子異常効果の検証

• Project Area: Quest on new hadrons with variety of flavors
• Project/Area Number: 24105707
• Research Category: Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area)
• Allocation Type: Single-year Grants
• Review Section: Science and Engineering
• Research Institution: Nara Women's University
• Principal Investigator: 永廣 秀子 奈良女子大学, 自然科学系, 助教 (10397838)
• Project Period (FY): 2012-04-01 – 2014-03-31
• Project Status: Completed (Fiscal Year 2013)
• Budget Amount: ¥3,510,000 (Direct Cost: ¥2,700,000、Indirect Cost: ¥810,000); Fiscal Year 2013: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000); Fiscal Year 2012: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000)
• Keywords: 中間子原子核 / 量子異常 / カイラル対称性

Research Abstract

本研究は、擬スカラー中間子の一つであるeta-prime(958)中間子に注目し、その有限密度中での質量減少の実験的な検証に向けた理論研究である。eta-prime(958)中間子は、南部-Goldstone粒子としては、重すぎる質量を持っており、これはUA(1)量子異常の存在とカイラル対称性の自発的破れがあいまって決定されていると考えられている。このことを踏まえ、有限密度中でのeta-prime(958)中間子の質量減少を観測することが出来れば、有限密度中でのカイラル対称性の自発的破れ及びUA(1)量子異常の振る舞いなどに関する知見が得られると考え、その実験的検証を目指すものである。
本研究では、eta-prime(958)中間子を原子核の束縛させ、そのスペクトラムをピークとして観測することで、eta-prime(958)中間子の質量減少の観測をめざしたものである。本年度は具体的に、原子核に陽子を入射させ、重陽子を観測する(p,d)反応による束縛状態生成に関し、最適な入射エネルギー、標的原子核などの具体的検証を行い、論文発表を行った。また、光子を入射させ陽子を観測する(gamma,p)反応に関しても、最適な実験条件を探るための理論研究を行い、実験研究者と議論を行った。さらに、微視的な相互作用から結合チャネル法を用いたeta-prime原子核光学ポテンシャルを導出し、エネルギー依存性を考慮した形で検証を行い、束縛エネルギー及び崩壊幅の見積もりを行った。さらにこの結合チャネルにおけるベクトル中間子の寄与に関して詳細に議論を行った。

Current Status of Research Progress

Reason

25年度が最終年度であるため、記入しない。

Strategy for Future Research Activity

25年度が最終年度であるため、記入しない。

Research Products

• [Journal Article] Role of vector and pseudoscalar mesons in understanding 1/2-N* and Delta resonances (2013)
  • Author(s): K.P.Khemchandani, A. Martinez Torres, H. Nagahiro, A. Hosaka
  • Journal Title: Physical Review D Volume: 88 Issue: 11
  • DOI: 10.1103/physrevd.88.114016
  • Peer Reviewed
• [Journal Article] Compositeness and elementary nature of a resonance in the sigma model (2013)
  • Author(s): Hideko Nagahiro, Atsushi Hosaka
  • Journal Title: Physical Review C Volume: 88 Issue: 5
  • DOI: 10.1103/physrevc.88.055203
  • Peer Reviewed
• [Journal Article] (d, 3He) reaction on an odd-neutron nuclear target for the formation of deeply bound pionic atoms (2013)
  • Author(s): N. Ikeno, J. Yamagata-Sekihara, H. Nagahiro, S. Hirenzaki
  • Journal Title: Progress of Theoretical and Experimental Physics Volume: 2013 Issue: 6
  • DOI: 10.1093/ptep/ptt035
  • Peer Reviewed
• [Journal Article] Complex 2D Matrix Model and Geometrical Map on Complex-Nc Plane (2013)
  • Author(s): Kanabu Nawa, Sho Ozaki, Hideko Nagahiro, Daisuke Jido, Atsushi Hosaka,
  • Journal Title: Progress of Theoretical and Experimental Physics Volume: 2013 Issue: 8
  • DOI: 10.1093/ptep/ptt051
  • Peer Reviewed
• [Journal Article] Formation of η' (958)-mesic nuclei by (p,d) reaction (2013)
  • Author(s): H. Nagahiro, D. Jido, H. Fujioka, K. Itahashi, S. Hirenzaki
  • Journal Title: Phys. Rev. Volume: C 87 Issue: 4 Pages: 45201-45201
  • DOI: 10.1103/physrevc.87.045201
  • Peer Reviewed
• [Journal Article] Resonances generated by the vector meson-baryon dynamics (2013)
  • Author(s): K.P. Khemchandani et al.
  • Journal Title: Few Body Syst. Volume: 54 Issue: 1-4 Pages: 343-346
  • DOI: 10.1007/s00601-012-0389-z
• [Journal Article] Composite and elementary components in hadron resonances (2013)
  • Author(s): Atsushi Hosaka et al.
  • Journal Title: Few Body Syst. Volume: 54 Issue: 1-4 Pages: 19-24
  • DOI: 10.1007/s00601-012-0375-5
• [Journal Article] Feasibility Study of Observing η'Mesic Nuclei with (p,d) Reaction (2012)
  • Author(s): Kenta Itahashi, Hiroyuki Fujioka他15名
  • Journal Title: Prog. Theor. Phys. Volume: 128 Issue: 3 Pages: 601-613
  • DOI: 10.1143/ptp.128.601
  • NAID: 110009517363
  • Peer Reviewed
• [Journal Article] Negative parity Λ and Σ resonances coupled to pseudoscalar and vector mesons (2012)
  • Author(s): K.P. Khemchandani , H. Nagahiro, A. Hosaka
  • Journal Title: Phys.Rev. D Volume: 85 Issue: 11 Pages: 114020-114020
  • DOI: 10.1103/physrevd.85.114020
  • Peer Reviewed
• [Journal Article] Formation of deeply bound pionic atoms in Sn isotopes (2012)
  • Author(s): Natsumi Ikeno, Hideko Nagahiro, Daisuke Jido and Satoru Hirenzaki
  • Journal Title: EPJ Web of Conferences Volume: 37 Pages: 090181-4
  • DOI: 10.1051/epjconf/20123709018
• [Journal Article] Formation of eta-prime(958) mesic nuclei (2012)
  • Author(s): Satoru Hirenzaki et al.
  • Journal Title: EPJ Web Conf. Volume: 37 Pages: 02001-02001
  • DOI: 10.1051/epjconf/20123702001
• [Journal Article] Spectroscopy of eta'-nucleus bound states at GSI-SIS (2012)
  • Author(s): Hiroyuki Fujioka et al.
  • Journal Title: EPJ Web Conf. Volume: 37 Pages: 02005-02005
  • DOI: 10.1051/epjconf/20123702005
• [Journal Article] Daisuke Jido, Hideko Nagahiro, Satoru Hirenzaki, and Shuntaro Sakai (2012)
  • Author(s): eta' meson under partial restoration of chiral symmetry in nuclear medium
  • Journal Title: EPJ Web of Conference Volume: 37 Pages: 09019-09019
  • DOI: 10.1051/epjconf/20123709019
• [Presentation] Composite and elementary natures of hadron resonances (2014)
  • Author(s): Hideko Nagahiro
  • Organizer: "Hirschegg2014", Hadrons from Quarks and Gluons
  • Place of Presentation: Hirschegg, Kleinwalsertal, Austria
• [Presentation] Study of mixing properties of mesonic resonances (2013)
  • Author(s): Hideko Nagahiro
  • Organizer: 第68回日本物理学会
  • Place of Presentation: 広島大学
  • Year and Date: 2013-03-26
• [Presentation] Spectroscopic study of eta’(958)-nucleus bound systems with (p,d) reaction (2013)
  • Author(s): Hideko Nagahiro
  • Organizer: Workshop on “Elucidation of New Hadrons with a Variety of Flavors"
  • Place of Presentation: 高エネルギー加速器研究機構
  • Year and Date: 2013-03-21
• [Presentation] eta'(958)-nucleus bound states and their formations by missing mass spectroscopies (2013)
  • Author(s): Hideko Nagahiro
  • Organizer: YITP workshop on "Hadrons in Nucleus"
  • Place of Presentation: Maskawa Hall, Kyoto University
• [Presentation] eta'(958) mesic nuclei formation by (p,d) reaction (2013)
  • Author(s): Hideko Nagahiro
  • Organizer: International Wokshop on "MesonNet Meeting"
  • Place of Presentation: Prague, Czech Republic
• [Presentation] Formation of eta’(958) nucleus bound state (2012)
  • Author(s): Hideko Nagahiro
  • Organizer: ELPH研究会『ダブルメソン生成とバリオン分光』
  • Place of Presentation: 東北大学
  • Year and Date: 2012-11-29
  • Invited
• [Presentation] Formation of the eta'(958)-mesic nuclei in missing mass spectroscopies (2012)
  • Author(s): Hideko Nagahiro
  • Organizer: 11th International Conference on Hypernuclear and Strange Particle Physics (HYP2012)
  • Place of Presentation: バルセロナ
  • Year and Date: 2012-10-01
• [Presentation] Formation of eta mesic nuclei and in-medium properties of hadrons (2012)
  • Author(s): Hideko Nagahiro
  • Organizer: International Workshop on Strangeness Nuclear Physics 2012
  • Place of Presentation: 大阪電気通信大学
  • Year and Date: 2012-08-27
  • Invited
• [Presentation] Formation of eta’(958) meson bound states and chiral symmetry in-medium (2012)
  • Author(s): Hideko Nagahiro
  • Organizer: The20th International IUPAP Conference on Few-Body Problem in Physics
  • Place of Presentation: 福岡国際会議場
  • Year and Date: 2012-08-20
• [Presentation] Composite and elementary natures of mesonic resonances (2012)
  • Author(s): Hideko Nagahiro
  • Organizer: 新学術領域「素核宇宙融合」×「新ハドロン」クロスオーバー研究会
  • Place of Presentation: 名古屋大学
  • Year and Date: 2012-07-12