在1996年至2018年期间在超级Kamiokande中寻找太阳 ^{8}B 中微子流的周期时间变化
K Abe1,2, C Bronner1, Y Hayato1,2
1Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo, Kamioka, Gifu 506-1205, Japan.
Physical review letters
|July 1, 2024
概括
超级Kamiokande数据分析了22年的太阳中微子相互作用,以寻找流量变化. 在{8}B中微子流中检测到的初级调制与地球圆轨道相关,而不是太阳活动.
科学领域:
- 粒子物理学 粒子物理学
- 天体物理学 天体物理学
- 太空物理学 太空物理学
背景情况:
- 太阳中微子流是太阳内部过程的关键指标.
- 了解中微子流量的变化可以揭示太阳活动和中微子属性的洞察力.
- 超级Kamiokande已经收集了数十年来关于太阳中微子相互作用的大量数据.
研究的目的:
- 为了寻找{8}B太阳中性子流的时间变化.
- 精确测量22年期间流量中的任何周期性调制.
- 调查中微子流与太阳或地球现象之间的潜在相关性.
主要方法:
- 利用了5804个活日的超级Kamiokande数据 (1996年5月 - 2018年5月).
- 采用最大概率方法来分析五天间隔的太阳中微子流量测量.
- 应用了Lomb-Scargle方法与以前的研究进行比较,并检测周期性.
主要成果:
- 没有发现可归因于太阳活动的显著周期调制.
- 观察到的唯一显著的调制与地球围绕太阳的圆轨道一致.
- 测量轨道异常率为 (1.53±0.35) %,周日偏移为 (-1.5±13.5) 天.
结论:
- {8}B太阳中微子流显示了超出地球轨道参数所造成的最小时间变化.
- 该研究提供了精确的测量,限制了太阳中微子流量调节的潜在来源.
- 结果证实了太阳中微子流在所研究的时间尺度上的稳定性,而地球轨道是主导因素.
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