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用詹姆斯·韦伯太空望远镜在红外背景中寻找暗物质线
1Fermi National Accelerator Laboratory, Theoretical Astrophysics Department, Batavia, Illinois 60510, USA.
Physical review letters
|March 7, 2025
概括
我们使用詹姆斯·韦伯太空望远镜 (JWST) 的数据来寻找正在衰变的暗物质粒子. 这项研究为1 eV左右的粒子提供了对暗物质衰变速率和轴子-光子合的新约束.
科学领域:
- 宇宙学的宇宙学是什么?
- 粒子物理学 粒子物理学
- 天体物理学 天体物理学
背景情况:
- 暗物质是宇宙的主要组成部分,但它的性质仍然是未知的.
- 一个暗物质候选物的子集,像axion-like粒子,可以分解成光子.
- 之前对衰变暗物质的搜索一直受到观测限制的限制.
研究的目的:
- 为了寻找暗物质粒子分解成近红外光子的证据.
- 在eV质量范围内,对暗物质的衰变速率产生新的,领先的约束.
- 为了特别约束像axion的粒子暗物质的轴子-光子合.
主要方法:
- 利用詹姆斯·韦伯太空望远镜 (JWST) 上的近红外光谱仪 (NIRSpec) 整体场单元 (IFU) 的公共空白天空观测.
- 寻找一个狭窄的辐射线签名,表明近红外光谱中的暗物质正在衰变.
- 分析数据以排除暗物质衰变速率和轴子-光子合的特定范围.
主要成果:
- 在0.8-3 eV的质量范围内的暗物质粒子的衰变速率上推导了主要约束.
- 不包括一个衰变寿命 τ < 3.5 × 10^26 s 在m_DM 0.8 eV.
- 限制了axion-photon合为g_aγγ > 1.3 × 10^-11 GeV^-1对于具有m_a 2.2 eV的axion样粒子.
结论:
- 这项研究表明,使用现有的JWST空白天空观测用于暗物质搜索的潜力.
- 由此产生的约束将大大提高我们对 eV级暗物质性质的理解.
- 未来的JWST观测将进一步提高这些搜索的灵敏度,可能导致直接检测衰变的暗物质.
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