Laboratory Measurements of N2 Reacting with H3+ Isotopologues and Implications for Deuterated Astrochemistry

N2 与 H3 同位素体反应的实验室测量及其对氘代天体化学的影响

• 批准号: 2002461
• 负责人: Daniel Wolf Savin
• 金额: $ 54.23万
• 依托单位: Columbia University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2002461&HistoricalAwards=false
• 关键词: Laboratory; Measurements; N2; Reacting; H3+

Molecular observations are important to understanding how the interstellar gas is converted to molecular clouds, stars, and planets. This research project will investigate the formation of the molecular ions N2H+ and N2D+, which are commonly used to trace properties of prestellar molecular clouds and protoplanetary disks. By means of a sophisticated laboratory experiment, the investigators will accurately determine the production rates of the ions at the very low temperatures relevant to interstellar clouds. Results from the study will allow astronomers to accurately determine the abundance of these ions in space and interpret observations of the earliest stages of star and planet formation. This project will contribute to the training and professional development of a postdoctoral scholar, provide research opportunities for undergraduates, and engage the public through lectures on astrochemistry.Using a dual-source, merged fast-beams apparatus, Savin and collaborators will measure accurate integral cross sections (ICS) for six reactions of N2 with H3+ and its deuterated forms as a function of the internal temperature of the reactants. The ICSs will allow the team to generate reliable thermal rate coefficients for N2H+ and N2D+ formation for use in astrochemical models. The measurements will also guide astrochemical models of deuterated molecules for which laboratory data are unavailable, and they will test the validity of approximations used to interpret branching fractions of partially deuterated molecules in space.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.

分子观测对于理解星际气体如何转化为分子云、恒星和行星非常重要。该研究项目将研究分子离子N2H+和N2D+的形成，这两种离子通常用于追踪恒星前分子云和原行星盘的性质。通过一个复杂的实验室实验，研究人员将准确地确定在与星际云相关的极低温度下离子的产生速率。这项研究的结果将使天文学家能够准确地确定这些离子在太空中的丰度，并解释恒星和行星形成最早阶段的观测结果。该项目将有助于培养和专业发展博士后学者，为本科生提供研究机会，并通过天体化学讲座吸引公众。使用双源、合并快光束装置，Savin和合作者将测量N2与H3+的六个反应的精确积分截面（ICS）及其氘化形式作为反应物内部温度的函数。ICSs将允许团队为N2H+和N2D+的形成生成可靠的热速率系数，用于天体化学模型。这些测量还将指导无法获得实验室数据的氘化分子的天体化学模型，并将测试用于解释空间中部分氘化分子分支部分的近似的有效性。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Laser cooling scheme for the carbon dimer ( C122 )

碳二聚体（C122）的激光冷却方案

• DOI: 10.1103/physreva.105.l051301
• 发表时间: 2022
• 期刊: Physical Review A
• 影响因子: 2.9
• 作者: Bigagli, Niccolò;Savin, Daniel W.;Will, Sebastian
• 通讯作者: Will, Sebastian

Branching Ratio for O + H 3 + Forming OH + + H 2 and H 2 O + + H

O H 3 形成OH H 2 和H 2 O H 的支化率

• DOI: 10.3847/1538-4357/ac41ce
• 发表时间: 2022
• 期刊: The Astrophysical Journal
• 作者: Hillenbrand, Pierre-Michel;Ruette, Nathalie de;Urbain, Xavier;Savin, Daniel W.
• 通讯作者: Savin, Daniel W.