使用BESS-Polar II磁刚性光谱仪寻找宇宙起源的反子
K Sakai1,2, H Fuke3, K Yoshimura4
1NASA-Goddard Space Flight Center (NASA-GSFC), Greenbelt, Maryland 20771, USA.
Physical review letters
|April 13, 2024
概括
研究人员在宇宙射线中没有发现反子 (d[over ̄]s),从而设定了一个新的流量极限. 这一结果改进了之前的实验,并为理论预测提供了关键数据.
科学领域:
- * 粒子天体物理学和宇宙学
- *宇宙射线物理学 *宇宙射线物理学
背景情况:
- *宇宙射线含有各种粒子,包括潜在的反物质成分.
- *反子 (d[over ̄]s) 是一些理论预测的,例如超对称,它们的检测可能表明新的物理学.
- *以前的实验已经寻找了抗子,但灵敏度有限.
研究的目的:
- * 在宇宙射线数据中搜索反子 (d[over ̄]s).
- * 为了确定抗素流量的上限.
- * 测试银河系中抗素生产的理论预测.
主要方法:
- * 分析了在太阳最小值BESS-Polar II飞行 (2007-2008) 期间收集的4.7×109个宇宙射线事件.
- *使用敏感探测器识别和区分抗子与其他宇宙射线粒子.
- *计算了95%的置信度 (C.L.) 抗氨酸流量的上限.
主要成果:
- *在观测到的宇宙射线事件中没有检测到抗素候选物.
- *一个95%的C.L. 在0.163和1.100GeV/n之间的能量下,抗德流的上限被确定为6.7×10−5 (m2 s sr GeV/n) −1.
- * 这一极限代表了显著的改善,比BESS97实验之前的极限低14倍以上.
结论:
- * BESS-Polar II实验设定了迄今为止最严格的抗素流量的上限.
- * 这一结果达到限制目前抗素生产理论模型所需的灵敏度.
- * 缺乏已检测到的反子对预测它们在宇宙射线中的丰度的理论提出了限制.
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