• Search Research Projects
  • Search Researchers
  • How to Use
  1. Back to previous page

Study on the contributions of the alpha-induced reactions in the explosive hydrogen-burning processes by direct and indirect measurements

Research Project

Project/Area Number 18K13556
Research Category

Grant-in-Aid for Early-Career Scientists

Allocation TypeMulti-year Fund
Review Section Basic Section 15020:Experimental studies related to particle-, nuclear-, cosmic ray and astro-physics
Research InstitutionThe University of Tokyo

Principal Investigator

Hayakawa Seiya  東京大学, 大学院理学系研究科(理学部), 特任助教 (00747743)

Project Period (FY) 2018-04-01 – 2023-03-31
Project Status Completed (Fiscal Year 2022)
Budget Amount *help
¥4,290,000 (Direct Cost: ¥3,300,000、Indirect Cost: ¥990,000)
Fiscal Year 2021: ¥390,000 (Direct Cost: ¥300,000、Indirect Cost: ¥90,000)
Fiscal Year 2020: ¥520,000 (Direct Cost: ¥400,000、Indirect Cost: ¥120,000)
Fiscal Year 2019: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000)
Fiscal Year 2018: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000)
Keywords宇宙核物理学 / 不安定核ビーム実験 / 直接測定 / トロイの木馬法 / X線バースト / αp過程 / rp過程 / 元素合成 / 原子核物理学実験 / 不安定核ビーム / 冷却気体標的開発 / 冷却期待標的開発 / 爆発的水素燃焼過程 / (α,p)反応直接測定
Outline of Final Research Achievements

This study aimed at understanding of explosive nucleosynthetic process through measurements of a nuclear reaction cross section which is strongly related to the observed light curves of X-ray bursts. Initially, we planed 1) 26Si radioactive-isotope beam production test 2) direct measurement by thick target method, and 3) indirect measurement by Trojan Horse method. We were only able to complete 1) and 2) in the covid-19 situation; the accelerator experiments were suspended for some period, and even after it resumed, foreign participants could not come to Japan. The direct-measurement data indicate possibility that the reaction cross-sections are more than one order of magnitude smaller than those predicted by theoretical statistical models. This research is also subjects for the master's thesis and the doctoral dissertation of a Japanese student and a Korean student, respectively, and we are also preparing to submit a paper.

Academic Significance and Societal Importance of the Research Achievements

X線バーストの観測結果を説明するための天体理論モデルは、多くの原子核反応が関わる反応ネットワークに強く依存する。しかし、不安定核を含む原子核反応の断面積測定は技術的に難しく、多くの反応においていまだに十分な実験データが得られていない。本研究では重要な反応の一つ、26Si(α,p)29P反応を新たなアプローチで測定することにより、X線バースト研究に打開をもたらしうると考えている。実験からは、理論的な統計モデル断面積と比べて、測定結果が1桁以上小さいという可能性が明らかになりつつある。本研究により、原子核実験に留まらず、原子核理論、天体物理理論などへ新たな知見をもたらせる可能性を期待している。

Report

(6 results)
  • 2022 Annual Research Report   Final Research Report ( PDF )
  • 2021 Research-status Report
  • 2020 Research-status Report
  • 2019 Research-status Report
  • 2018 Research-status Report
  • Research Products

    (2 results)

All 2023 2022

All Journal Article (1 results) (of which Int'l Joint Research: 1 results,  Peer Reviewed: 1 results,  Open Access: 1 results) Presentation (1 results)

  • [Journal Article] Direct measurement of the 26Si(α, p)29P reaction at CRIB for the nucleosynthesis in the X-ray bursts2023

    • Author(s)
      Kodai Okawa, Minju Kim, Kyungyuk Chae, Seiya Hayakawa, et al.
    • Journal Title

      European Physical Journal Web Conferences

      Volume: 275 Pages: 02009-02009

    • DOI

      10.1051/epjconf/202327502009

    • Related Report
      2022 Annual Research Report
    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Presentation] Direct measurement of 26Si(α, p)29P reaction at CRIB for the nucleosynthesis in X-ray bursts2022

    • Author(s)
      大川皓大
    • Organizer
      日本物理学会2022年秋季大会
    • Related Report
      2022 Annual Research Report

URL: 

Published: 2018-04-23   Modified: 2024-01-30  

Information User Guide FAQ News Terms of Use Attribution of KAKENHI

Powered by NII kakenhi