靠近的类似太阳的恒星的光谱微观结构常数变化的极限
Michael T Murphy1, Daniel A Berke1, Fan Liu
1Centre for Astrophysics and Supercomputing, Swinburne University of Technology, Hawthorn, Victoria 3122, Australia.
概括
细结构常数 (α) 可能有所变化,影响电磁性. 研究人员在附近的恒星中测量了α,
科学领域:
- * 天体物理学和粒子物理学.
- 调查自然界的基本力量.
背景情况:
- * 精细结构常数 (α) 的值未被标准模型解释,可能有所变化.
- * 恒星吸收线依赖于α,但受到恒星大气过程的影响.
研究的目的:
- * 精确测量附近恒星的微型结构常数 (α).
- * 调查我们当地的宇宙邻里中α的潜在变化.
- * 为恒星α测量建立一个精确的经验参考.
主要方法:
- * 从17颗类似太阳的恒星 (太阳双胞胎) 观察到精确的恒星吸收线波长.
- * 选择了与太阳几乎相同的大气特性的恒星,以尽量减少系统错误.
- * 分析数据以检测细结构常数 (α) 的变化.
主要成果:
- * 检测到微观结构常数 (α) 在50帕塞克内的千亿分之一的变化.
- * 在恒星α测量中获得了10亿分之12的整体精度.
- 证明使用太阳双子来减少天体物理系统效应的可行性.
结论:
- * 微型结构常数 (α) 呈现局部变化,挑战目前的物理模型.
- * 这项研究为测量恒星环境中的α提供了一个新的,高度精确的局部参考.
- 未来的研究可以在这些发现的基础上探索α变化的性质和程度.
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