PM: Cold Radioactive Molecules for Precision Measurements.

PM：用于精密测量的冷放射性分子。

• 批准号: 2309361
• 负责人: Nicholas Hutzler
• 金额: $ 64.31万
• 依托单位: California Institute of Technology
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-07-01 至 2026-06-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2309361&HistoricalAwards=false
• 关键词: PM; Cold; Radioactive; Molecules; Precision

The fact that the Universe is made from matter, yet contains no anti-matter, is a mystery. Nobody knows which physical process was responsible for generation of matter in the early Universe, but we do know that it can manifest itself in some unusual ways. One way is by modifying the electromagnetic properties of nuclei, which can be studied precisely in a table-top setting using laser-controlled and atoms and molecules. Some nuclei are more sensitive than others to these effects, and it has been known for decades that polar molecules containing certain heavy, unstable nuclei in the last row of the periodic table amplify the effects of this new physics by around a million times compared to current state-of-the-art experiments. However, these gains remain unrealized; the complexity of even the simplest molecule, combined with the limited amounts of unstable nuclei which can be obtained and handled in the laboratory, made this research very challenging. Indeed, the first precise laser-based measurement of any radioactive molecule was first performed a few years ago. For this present study, the PI will lead a team of students to develop and demonstrate a new method to synthesize, cool, and precisely study the structure and properties of molecules containing radium – one of the nuclei with the highest sensitivity to new fundamental physics. The research team will combine laser-driven chemical reactions, cryogenic helium gas cooling, and new approaches to precision spectroscopy to study polyatomic radium-containing molecules, whose chemical structures are tuned to enable advanced quantum control to study these exotic nuclei. Furthermore, the method will be widely applicable to molecules containing unstable or rare nuclei for studies in nuclear structure, radiochemistry, and nuclear astrophysics.Molecules containing heavy, octupole-deformed nuclei, such as radium, offer extreme enhancement of hadronic CP-violation. The combination of the intermolecular electromagnetic environment and the shape deformation of the nucleus result in around a million-fold enhancement in sensitivity to CP-violating nuclear Schiff moments compared to state-of-the-art experiments using atoms with spherical nuclei. Furthermore, many radium-containing molecules are predicted to be laser-coolable, meaning that they offer an avenue to advanced quantum control for highly sensitive measurements. However, the difficulty of working with these species has stifled their study; indeed, only in the last few years has precision spectroscopy been performed on any short-lived radioactive molecular species. The goal of this research program is to synthesize, cool, and spectroscopically study radium-containing polyatomic molecules, including RaOH, by combining laser-driven chemical synthesis, cryogenic buffer gas cooling, and new approaches to both broadband and narrowband spectroscopy with very small quantities of material. The method will produce molecules which are rotationally and translationally cooled to around 4 K in a static buffer gas cell, thereby placing them at a starting point for spectroscopy, laser cooling, and precision measurements. Furthermore, the methods will be very general, and can be applied to a wide variety of molecules containing exotic nuclei or otherwise available only in trace amounts.This 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.

宇宙是用物质制成的，但没有反物质，这是早期宇宙中物质的谜核和分子的某些核比其他核更重要，而且几十年来，它已经众所周知，确定了与当前的thysics相比的重度，不稳定的nust nust行但是，某些实验。本研究，PI -RONG -ADENTENT，证明了一种新方法来综合分子的特性，包括镭的分子 - 具有新基本物理学的核之一。冷却和新方法是奥属辐射分子，其化学成分可实现晚期cuantum contum contum contum controgotic n核。 -Formed的核（例如镭）极大地增强了Hadronic CP侵入的极端增强，他间分子电磁环境的核结果IND核结果IND在Censitity-Censitity-violle核能Schiff schiff矩矩矩矩矩矩强的实验中使用与构成原子的实验相比，核酸的增强量增加了数百万倍的增强。预计ECULE是可以进行激光的，这意味着它们可以对高度敏感的量子进行高级量子控制。 ，通过将激光驱动的化学合成，低温缓冲液冷却和新的apporoches与宽带光谱和光谱谱系相结合，并将光谱分子与光谱与材料与静态缓和型宽带频谱和窄带光谱相结合，从而将多原子分子（包括RAOH）研究。此外，这些方法将应用于仅在种族金额中可用的大量分子或Orwise分子上。该奖项反映了NSF的Beenend Demed值得支持基金会的功绩和更广泛的影响审查标准。