一条连续的银河系线 轴子的来源:NaNa的非凡案例
W C Haxton1,2,3, Xing Liu1, Annie McCutcheon4
1University of California, Berkeley, Department of Physics, California 94720, USA.
Physical review letters
|December 12, 2025
概括
恒星中的-23 (Na) 可能会产生银河系轴子. 这些轴子可以转化为光子,为像COSI这样的望远镜创建可检测的440 keV马射线信号.
科学领域:
- 天体物理学 天体物理学
- 粒子物理学 粒子物理学
- 核物理 核物理 核物理
背景情况:
- 轴子是假设的粒子,可以解决粒子物理学中的强 CP 问题.
- 巨大的恒星在进化过程中合成了像这样的元素.
- 恒星环境达到极端温度,影响核过程.
研究的目的:
- 调查-23 (Na) 作为银河系轴子源的潜力.
- 为了确定恒星中的轴动产能否导致可观测的天体物理信号.
- 用当前和未来的马射线望远镜评估这些轴子的检测能力.
主要方法:
- 利用MESA (恒星天体物理学实验模块) 模拟来建模恒星进化和核合成.
- 开发了一种银河系模型来模拟地球上的轴动流.
- 在各种原始质量,位置和进化阶段进行采样.
主要成果:
- 确定了440keV激发状态的Na在碳燃烧的特征温度 (7×108K) 时被热填充.
- 计算了地球上的轴子的连续流量 (φ_{a}≈22/cm2s对于g_{aNN}^{eff}=10−9).
- 预测,银河系磁场中的axion-to-photon转换会产生一个可检测的440 keV的马射线线.
结论:
- {}^{23}Na是银河系轴子的一个潜在的重要来源.
- 预测的440 keV马射线可以通过像COSI这样的全天马射线探测器来检测.
- 未来使用COSI进行的观测可以探测新的参数空间,以检测轴子属性 (dakg_{aNN}^{eff}g_{aγγ}dakg1.8×10−22 GeV−1).
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