CAREER: Non-Adiabatic Effects in Dense Plasmas

职业：致密等离子体中的非绝热效应

• 批准号: 2045718
• 负责人: Thomas White
• 金额: $ 75.38万
• 依托单位: Board of Regents, NSHE, obo University of Nevada, Reno
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-02-15 至 2026-01-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2045718&HistoricalAwards=false
• 关键词: CAREER; Non; Adiabatic; Effects; Dense

This CAREER award supports exploration of some of the most extreme states of matter we know to exist in the universe and can probe in a laboratory setting. All visible matter is made up of two components, heavy nuclei surrounded by much lighter electrons. The slow-moving nuclei are often assumed to respond weakly to the electrons hurtling around them. This premise is the cornerstone of modern simulation techniques in both physics and chemistry. However, extreme environments, such as in the center of planets and stars, create incredibly hot dense matter. This results in fast-moving electrons that begin to strongly interact with the slow-moving nuclei, challenging previous assumptions. This award supports experimental work at some of the world's largest lasers, including the National Ignition Facility - the world's most energetic laser. The harsh astrophysical conditions will be recreated on Earth to measure the nuclei dynamics in regimes where data is scarce. Measurements of fundamental quantities, including particle diffusion and sound speed, will be used to validate state-of-the-art quantum mechanical simulations. The project will help train the next generation of scientists by offering education and research opportunities to the global plasma community. The education and outreach will focus on providing underrepresented students access to and training in high-performance computing techniques.Simulations of dense plasmas typically employ the adiabatic approximation, usually justified through the disparate energy scales of the electron and ion motion. The electrons are assumed to instantaneously adjust to the ion fields, while the ions are confined to a single adiabatic surface. Recent approaches that go beyond this approximation have led to significant differences in the predictions of plasma properties, with a dearth of experimental measurements preventing discrimination between competing models. This research program will employ a new experimental platform, developed for the Omega and NIF laser facilities, to perform the first measurement of diffusion in the warm dense matter regime. This platform will employ Fresnel Diffractive Radiography, a novel diagnostic technique for laser-driven X-rays that measures the slow, diffusion-driven changes in density gradients with exceptional spatial resolution. The experimental work is supported by predictions of the diffusion coefficient using new advanced simulations that incorporate the electron dynamics within a complex, quantum-mechanical framework. These simulations will be conducted by undergraduate students and performed with support from the University of Nevada, Reno High-Performance Computing team. The primary research goal is to clearly discriminate between plasma models with fundamentally different approaches to non-adiabaticity. This project is jointly funded by the Division of Physics and the Established Program to Stimulate Competitive Research (EPSCoR).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.

该职业奖支持探索我们所知的宇宙中存在的一些最极端的物质状态，并且可以在实验室环境中进行探测。 所有可见物质都由两种成分组成，重的原子核被轻得多的电子包围。人们通常认为移动缓慢的原子核对其周围的电子反应较弱。这个前提是现代物理和化学模拟技术的基石。然而，极端环境，例如行星和恒星的中心，会产生极其热的致密物质。 这导致快速移动的电子开始与缓慢移动的原子核发生强烈相互作用，挑战了之前的假设。该奖项支持一些世界上最大的激光器的实验工作，包括国家点火设施——世界上能量最高的激光器。恶劣的天体物理条件将在地球上重现，以测量数据稀缺地区的核动力学。包括粒子扩散和声速在内的基本量的测量将用于验证最先进的量子力学模拟。 该项目将通过向全球血浆界提供教育和研究机会来帮助培训下一代科学家。 教育和推广将侧重于为代表性不足的学生提供高性能计算技术的机会和培训。稠密等离子体的模拟通常采用绝热近似，通常通过电子和离子运动的不同能量尺度来证明其合理性。假设电子立即适应离子场，而离子被限制在单个绝热表面。最近超越这种近似的方法导致等离子体特性的预测存在显着差异，由于缺乏实验测量，无法区分竞争模型。该研究计划将采用为 Omega 和 NIF 激光设施开发的新实验平台，首次测量温暖致密物质区域的扩散。该平台将采用菲涅尔衍射射线照相技术，这是一种激光驱动 X 射线的新型诊断技术，能够以卓越的空间分辨率测量密度梯度中缓慢的、扩散驱动的变化。实验工作得到了使用新的高级模拟对扩散系数的预测的支持，该模拟将电子动力学纳入复杂的量子力学框架中。 这些模拟将由本科生进行，并得到内华达大学里诺分校高性能计算团队的支持。 主要研究目标是清楚地区分具有根本不同的非绝热性方法的等离子体模型。 该项目由物理部和刺激竞争研究既定计划 (EPSCoR) 联合资助。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力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

Insensitivity of a turbulent laser-plasma dynamo to initial conditions

湍流激光等离子体发电机对初始条件的不敏感性

• DOI: 10.1063/5.0084345
• 发表时间: 2022
• 期刊: Matter and Radiation at Extremes
• 影响因子: 5.1
• 作者: Bott, A. F.;Chen, L.;Tzeferacos, P.;Palmer, C. A.;Bell, A. R.;Bingham, R.;Birkel, A.;Froula, D. H.;Katz, J.;Kunz, M. W.
• 通讯作者: Kunz, M. W.

Diffraction enhanced imaging utilizing a laser produced x-ray source

利用激光产生的 X 射线源进行衍射增强成像

• DOI: 10.1063/5.0091348
• 发表时间: 2022
• 期刊: Review of Scientific Instruments
• 影响因子: 1.6
• 作者: Oliver, M.;Allen, C. H.;Divol, L.;Karmiol, Z.;Landen, O. L.;Ping, Y.;Wallace, R.;Schölmerich, M.;Theobald, W.;Döppner, T.
• 通讯作者: Döppner, T.

Disentangling the effects of non-adiabatic interactions upon ion self-diffusion within warm dense hydrogen

• DOI: 10.1098/rsta.2023.0034
• 发表时间: 2023-08-21
• 期刊: PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES
• 影响因子: 5
• 作者: Angermeier, William A.;Scheiner, Brett S.;White, Thomas G.
• 通讯作者: White, Thomas G.

A molecular dynamics study of laser-excited gold

• DOI: 10.1063/5.0073217
• 发表时间: 2022-05-01
• 期刊: MATTER AND RADIATION AT EXTREMES
• 影响因子: 5.1
• 作者: Molina, Jacob M.;White, T. G.
• 通讯作者: White, T. G.