Theoretical study of dark matter search using neutron stars

2023 Fiscal Year Final Research Report

• Project/Area Number: 20H01897
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 15010:Theoretical studies related to particle-, nuclear-, cosmic ray and astro-physics
• Research Institution: The University of Tokyo
• Principal Investigator: Hamaguchi Koichi 東京大学, 大学院理学系研究科(理学部), 准教授 (80431899)
• Co-Investigator(Kenkyū-buntansha): 永田 夏海 東京大学, 大学院理学系研究科(理学部), 助教 (60794328)
• Project Period (FY): 2020-04-01 – 2024-03-31
• Keywords: 中性子星 / 暗黒物質 / 標準模型を超える物理

Outline of Final Research Achievements

The aim of this study is to quantify the prospects with regard to the possibility of probing dark matter signals through future observations of neutron stars. The following results were obtained.
- The neutron star capture rate of electroweak multiplet dark matter is systematically calculated, and it is shown that future direct dark matter search experiments and searches based on neutron star surface temperature observations can play a complementary role and may probe these dark matter models.
- The neutron star heating effect caused by the friction of the neutron superfluid vortex creep is studied, and it is shown that the theoretical prediction of neutron star surface temperatures with this effect is a good explanation of the observed data. It is also argued that, if this heating effect exists, the heating effect associated with the capture of dark matter in neutron stars is masked.

Free Research Field

素粒子理論

Academic Significance and Societal Importance of the Research Achievements

・電弱多重項暗黒物質の研究においては、将来の暗黒物質直接探索実験と中性子星表面温度観測による探索が相補的な役割を果たすことを示した。これは直接探索実験の研究にとっても重要な意義を持つ。
・中性子超流動渦糸の運動に伴う摩擦により生じる中性子星加熱効果の研究結果は、素粒子分野で近年注目を集めている一連の研究（中性子星温度観測を用いた暗黒物質探索の可能性の研究）に一石を投じるもので、非常に重要な成果である。