Theoretical study towards the indirect detection of the axion dark matter by the observation of neutron star

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K14708
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 15010:Theoretical studies related to particle-, nuclear-, cosmic ray and astro-physics
• Research Institution: Tohoku University
• Principal Investigator: Naoya Kitajima 東北大学, 学際科学フロンティア研究所, 助教 (50737955)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 暗黒物質 / アクシオン

Outline of Final Research Achievements

In this research project, I have focused on a hypothetical particle “axion” as one of the plausible candidates for the dark matter in our Universe and performed theoretical analysis towards the possibility of indirect detection of the axion with the observation of the neutron star. Particularly focusing on the tiny interaction of the axion with the electromagnetic fields around the neutron star, I have developed numerical simulation code to follow the dynamics of the system.
This code has also been applied for the analysis of resonance phenomena of the axion and gauge fields in the early Universe and consequently we have pointed out a new possibility of the production of the dark photon dark matter and gravitational waves.

Free Research Field

宇宙論

Academic Significance and Societal Importance of the Research Achievements

これまでの観測データにより、現在の我々の宇宙は正体不明の暗黒物質で満たされていることが明らかにされており、その正体解明は我々の住む宇宙の起源の解明と密接に結びついている。また、暗黒物質は未知の素粒子であるという説が有力であることから、暗黒物質の検出は素粒子の新理論発見につながる。本研究成果は、暗黒物質の一つの有力な理論モデルについて宇宙の観測対象への示唆を与えたという意味で、既存の理論と将来観測の間の橋渡しを担う。