反质子对质子电荷对质量比的高精度比较
S Ulmer1, C Smorra2, A Mooser1
1RIKEN, Ulmer Initiative Research Unit, Wako, Saitama 351-0198, Japan.
Nature
|August 14, 2015
概括
这项研究精确地比较了反质子和质子的特性,证实了电荷,平价,时间逆转 (CPT) 对称性. 这些发现强烈支持CPT的不变性,并测试基本的物理原理.
科学领域:
- 粒子物理学
- 基本对称性
- 反物质研究
背景情况:
- 电荷,平价,时间逆转 (CPT) 不变是标准模型的基石,意味着物质与反物质的对称性.
- 之前的CPT测试依赖于间接方法; 直接,高精度的物质和反物质特性比较很少.
- 洛伦兹对称,即时空变换下的物理定律的不变性,与CPT不变性密切相关.
研究的目的:
- 进行高精度的对抗质子和质子的电荷-质量比较.
- 通过比较物质和反物质的基本性质,直接测试CPT对称性.
- 对CPT和洛伦兹对称的潜在违规设定新的极限,并测试弱等效原则.
主要方法:
- 使用宁陷系统来限制和测量单个反质子和离子 (H-) 的周期频率.
- 进行了超过13,000次频率测量,以实现高精度的电荷-质量比较.
- 分析了大约29.6兆赫的旋转频率.
主要成果:
- 发现反质子相对于质子的电荷-质量比与CPT不变相一致,精度为69 parts per trillion.
- 这一结果表明CPT对称性在atto电子电压能量尺度上成立.
- 对星际变化 (<720万亿分之一) 和引力异常参数建立了严格的限制 (gadgadα − 1gadgad < 8.7 × 10(-7).
结论:
- 这项研究提供了迄今为止最精确的CPT对称性测试,通过比较物质和反物质.
- 这些发现加强了CPT定理和标准模型的有效性.
- 结果为微粒子反物质的弱等价原理提供了重要的测试,对广义相对论有影响.
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