Collaborative Research: Precision Tests of Physics Beyond the Standard Model with Antihydrogen

这项研究是阿尔法合作的一部分，目的是寻找氢和反氢之间的性质差异，反氢是氢的反物质对应物。根据我们对物理世界的数学描述所依据的非常普遍的原理，反氢的原子物理应该与氢的原子物理相同。反氢和氢之间在原子物理或引力动力学方面的任何差异都将挑战我们周围世界既定的数学描述的基础。这项合作的高精度测量可能会揭示物理学中最重要的问题之一，即重子不对称，即在可观测的宇宙中，物质相对于反物质的优势。这一奖项是根据NSF/美国能源部在基础等离子体科学和工程方面的合作伙伴关系颁发的，将支持普渡大学和加州大学伯克利分校的一名本科生的合作努力，作为对联合计划下的能源部奖项的补充。这项研究是阿尔法合作的一部分，其目的是寻找氢和反氢性质之间的差异；这种差异只能由电荷-宇称时间(CPT)或弱等价原理违反而产生。欧洲核子研究中心的阿尔法合作已经从捕获反氢到测量它的正电子自旋翻转频率，有点粗略地测量了它的引力性质，它的电荷中性，它的1S-2S光谱，以及它的超精细光谱。预计在本供资期间，所有这些衡量标准的精确度将大大提高。近期，阿尔法正在建造并有望安装一台新的垂直实验设备ALPHAg，以进行上下重力测量。同时，它将继续对反氢的光学光谱和超精细光谱进行测量。在即将到来的为期两年的欧洲核子研究中心关闭期间，阿尔法将全面准备ALPHAg，并将建立一个新的原子光谱陷阱，阿尔法-III。在资助的最后两年，计划要求利用精细的磁测量技术进行高精度测量，以在1%的水平上进行重力测量；并将激光和绝热冷却应用于兰姆位移、反里德堡常数、电荷中性和超精细光谱的高精度测量。此外，与许多CPT测试不同，Alpha的测试是独立于模型的，不假定特定的CPT破坏机制。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

The goal of this research, part of the ALPHA Collaboration, is to search for differences between the properties of hydrogen and antihydrogen, the antimatter counterpart to hydrogen. According to very general principles that underlie our mathematical description of the physical world, the atomic physics of antihydrogen should be identical to that of hydrogen. Any differences in the atomic physics or gravitational dynamics between antihydrogen and hydrogen would challenge the very basis of established mathematical descriptions of the world around us. The collaboration's high-precision measurements may shed light on one of the most important questions in physics, known as the baryon asymmetry, which is the preponderance of matter over antimatter in the observable universe. This award is made under the NSF/DOE Partnership in Basic Plasma Science and Engineering and will support the collaboration's effort at Purdue University and an undergraduate student at University of California, Berkeley as complementary to a DOE award made under the joint program. The goal of this research, part of the ALPHA Collaboration, is to search for differences between the properties of hydrogen and antihydrogen; such differences could only result from Charge-Parity-Time (CPT) or Weak Equivalence Principle violation. The ALPHA collaboration at CERN has progressed from trapping antihydrogen to measuring its positron spin flip frequency, somewhat crudely its gravitational properties, its charge neutrality, its 1S-2S spectrum, and its hyperfine spectrum. Significant improvement in the precision of all these measurements is expected during the duration of this funding period. In the near term, ALPHA is constructing, and is expected to install, a new vertical experimental apparatus, ALPHAg, to conduct an up/down gravity measurement. In parallel, it will continue measurements on the optical and hyperfine spectra of antihydrogen. During the upcoming two-year CERN shutdown, ALPHA will fully prepare ALPHAg and will build a new atomic spectrum trap, ALPHA-III. During the final two years of funding, plans call for carrying out high-precision measurements utilizing fine scale magnetometry for gravity measurements at the 1% level; and applying laser and adiabatic cooling for high-precision measurements of the Lamb shift, the anti-Rydberg constant, charge neutrality, and the hyperfine spectrum. Moreover, unlike many CPT tests, ALPHA's tests are model-independent and do not presume a particular CPT breaking mechanismThis award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.