Search for cosmic-ray anti-protons produced through Hawking radiation of primordial black holes

• Project/Area Number: 15340077
• 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: High Energy Accelerator Research Organization (2006); Kobe University (2003-2005)
• Principal Investigator: NOZAKI Mitsuaki High Energy Accelerator Research Organization, Institute of Particle and Nuclear Studies, Professor (10156193)
• Project Period (FY): 2003 – 2006
• Project Status: Completed (Fiscal Year 2006)
• Budget Amount: ¥15,100,000 (Direct Cost: ¥15,100,000); Fiscal Year 2006: ¥1,200,000 (Direct Cost: ¥1,200,000); Fiscal Year 2005: ¥2,400,000 (Direct Cost: ¥2,400,000); Fiscal Year 2004: ¥3,600,000 (Direct Cost: ¥3,600,000); Fiscal Year 2003: ¥7,900,000 (Direct Cost: ¥7,900,000)
• Keywords: antiproton / cosmic-ray / balloon / Antarctica / Hawking radiation / Primordial black hole / 宇宙線反陽子

Research Abstract

The purpose of this program is to search for cosmic-ray antiprotons produced through Hawking radiation of primordial black holes at the top of the atmosphere by using a balloon-borne apparatus. Keys to this experiment are an apparatus capable of measuring low energy antiprotons below 1 GeV characteristic of Hawking radiation and a long duration flight at Antarctica to improve statistics.
We have developed time-of-flight (TOF) counters and middle-TOF counters and related read-out electronics. The TOF counters are used to distinguish antiprotons from electron. The middle-TOF counters installed in a small gap between a central tracker and a cryostat are used to trigger low energy particles that cannot penetrate a superconducting coil.
In December 2004, the BESS-Polar spectrometer was launched from McMurdo base in Antarctica. A total of 432 antiproton events were recorded in a 8.5 day flight. The number of antiprotons was 4 times larger than previous flight. We have measured antiprotons below 0.2 GeV for the first time. The energy spectrum obtained in this experiment is consistent with a secondary production model and we found no evidence for the antiprotons from Hawking radiation.

Research Products

• [Journal Article] Search for Primordial Antiparticle with BESS (2007)
  • Author(s): A. Yamamoto, 他
  • Journal Title: Adv.Space Res. (印刷中)
  • Description: 「研究成果報告書概要(和文)」より
• [Journal Article] BESS-Polar Experiment (2007)
  • Author(s): K. Yoshimura, 他
  • Journal Title: Adv.Space Res. (印刷中)
  • Description: 「研究成果報告書概要(和文)」より
• [Journal Article] The BESS Program (2007)
  • Author(s): A. Yamamoto, 他
  • Journal Title: Nucl.Phys.B(Proc.Suppl.) 116 Pages: 62-62
  • Description: 「研究成果報告書概要(和文)」より
• [Journal Article] Measurements of O.2 to 20 GeV/n cosmic-ray proton and helium spectra from 1997 through 2002 with the BESS spectrometer (2007)
  • Author(s): Y. Shikaze, 他
  • Journal Title: Astroparicle Phys. (印刷中)
  • Description: 「研究成果報告書概要(和文)」より
• [Journal Article] Search for Antihelium with BESS (2007)
  • Author(s): M. Sasaki, 他
  • Journal Title: Adv.Space Res. (印刷中)
  • Description: 「研究成果報告書概要(和文)」より
• [Journal Article] B. Search for Primordial Antiparticle with BESS (2007)
  • Author(s): A.Yamamoto, et. al.
  • Journal Title: Ad. Space Res. (in print)
  • Description: 「研究成果報告書概要(欧文)」より
• [Journal Article] BESS-Polar Experiment (2007)
  • Author(s): K.Yoshimura, et. al.
  • Journal Title: Adv. Space Res. (in print)
  • Description: 「研究成果報告書概要(欧文)」より
• [Journal Article] The BESS Program (2007)
  • Author(s): A.Yamamoto, et. al.
  • Journal Title: Nucl. Phys. b(Proc. Suppl.) 116 Pages: 62-62
  • Description: 「研究成果報告書概要(欧文)」より
• [Journal Article] Measurements of 0.2 to 20 GeV/n cosmic-ray proton and helium spectra from 1997 through 2002 with the BESS spectrometer (2007)
  • Author(s): Y.Shikaze at al.
  • Journal Title: Astroparticle Phys. (in print)
  • Description: 「研究成果報告書概要(欧文)」より
• [Journal Article] Search for Antihelium with BESS (2007)
  • Author(s): M.Sasaki, et. al.
  • Journal Title: Adv. Space Res.(in print)
  • Description: 「研究成果報告書概要(欧文)」より
• [Journal Article] The BESS Program (2007)
  • Author(s): A.Yamamoto, et al.
  • Journal Title: Nuclear Physics B Proceedings Suppplements 166 Pages: 62-67
• [Journal Article] Measurements of atmospheric antiprotons (2006)
  • Author(s): K.Yamato et al.
  • Journal Title: Physics Letters B 632 Pages: 475-479
• [Publications] M.Motoki, M Nozaki 他: "Precise measurements of atmospheric muon fluxes with the BESS spectrometer"Astroparticle Physics. 19. 113-126 (2003)
• [Publications] M.Nozaki: "BESS-Polar"Nuclear Instruments and Methods in Physics Research. B214. 110-115 (2004)