MRI: Acquisition of a TPX3Cam for High-Rate Coincidence Velocity Map Imaging

摘要：这项重大研究仪器奖资助了一种混合硅像素探测器和集成电子器件，称为TPX3Cam，供奥古斯塔纳大学、玛丽华盛顿大学、弗吉尼亚大学、密歇根州立大学和堪萨斯州立大学等五所机构合作使用。合作的研究人员对使用TPX3Cam进行复杂的实验有共同的兴趣，这些实验可以用强烈的超短激光脉冲探测分子之间的相互作用。长期以来，在原子、分子和化学物理学中，观察和控制原子和分子的固有时间尺度一直是一个巨大的挑战。此外，随着混合硅像素探测器的广泛应用，处理探测器信息的协议和方法的发展可以加速该工具在科学、医学和工程等其他领域的传播。值得注意的是，TPX3Cam的集体使用将促进奥古斯塔纳大学（Augustana University）和玛丽华盛顿大学（University of Mary Washington）、主要为本科生服务的学校以及合作中的三所大型研究型大学之间的合作。这些努力将使本科生接触到最前沿的实验设施和研究成果，从而继续激励对stem相关教育的追求，并最终帮助培养高技能的劳动力。技术观众摘要：TPX3Cam将用于多个粒子的相关测量，从而重建分子动力学。当与超快激光源耦合时，实验将探测多原子分子的电离和结构演化，这是复杂量子系统的例子。由于混合像素探测器的工作方式与其他带电粒子探测器完全不同，TPX3Cam仪器将把这些照明测量扩展到标准延迟线阳极技术难以实现的情况。用这种新仪器进行的例子包括强场电离和分子的相干控制。分子的强场电离（SFI）导致涉及电子和核耦合运动的复杂动力学，通常涉及相关电子动力学，并被用作分子结构和动力学的探针。SFI还通过创造电子波包来实现阿秒科学，该电子波包随后被驱动与其母体原子或分子碰撞，从而产生阿秒光爆发。因此，SFI研究有许多基本的和应用驱动的原因。几十年来，多原子分子中的强场过程一直处于相干控制化学反应的前沿。利用成形超快激光脉冲的强场相干控制方法是影响化学动力学的一般方法，因为它们可以利用动态斯塔克位移和多光子过程来改变能量流。这些强场控制方法可以通过利用TPX3Cam独特的检测能力，针对非常特定的控制结果进行改进。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。

General audience abstract:This Major Research Instrumentation award funds the acquisition of a hybrid silicon pixel detector and integrated electronics, known as a TPX3Cam, for use by a collaboration of five institutions: Augustana University, the University of Mary Washington, the University of Virginia, Michigan State University, and Kansas State University. Researchers in the collaboration share a common interest in using the TPX3Cam to enable sophisticated experiments that probe the interactions of molecules with intense, ultrashort laser pulses. Observing and controlling atoms and molecules at their native timescales has long been a grand challenge in atomic, molecular, and chemical physics. Moreover, as hybrid silicon pixel detectors emerge into wider use, the development of protocols and methods for processing the information from the detector can accelerate the spread of this tool into other areas of science, medicine, and engineering. Notably, the collective use of the TPX3Cam will foster collaborations between Augustana University and the University of Mary Washington, schools that primarily serve undergraduate student populations, and the three large research universities in the collaboration. These efforts will expose undergraduate students to forefront experimental facilities and research efforts and thereby continue to motivate the pursuit of STEM-related education and eventually help produce a highly-skilled workforce.Technical audience abstract: The TPX3Cam will be used to make correlated measurements of multiple particles and thus the reconstruction of molecular dynamics. When coupled with ultrafast laser sources, the experiments will probe the ionization and structural evolution of polyatomic molecules, which are examples of complex quantum systems. Since hybrid pixel detectors operate in a fundamentally different manner than other charged particle detectors, the TPX3Cam instrument will extend these illuminating measurements to situations not easily accessed with standard delay-line anode technology. Examples to be conducted with this new instrumentation include strong field ionization and coherent control of molecules. Strong field ionization (SFI) of molecules results in complex dynamics involving coupled electronic and nuclear motion, often entails correlated electron dynamics, and is used as a probe for molecular structure and dynamics. SFI also enables attosecond science by creating the electron wave packet that subsequently is driven to recollide with its parent atom or molecule, resulting in an attosecond burst of light. Thus, there are numerous basic and application-driven reasons for SFI studies. Strong-field processes in polyatomic molecules are at the forefront of the decades-long pursuit of coherently controlled chemical reactions. Strong-field coherent control methods using shaped ultrafast laser pulses are a general approach to influencing chemical dynamics since they can exploit dynamic Stark shifts and multiphoton processes to alter energy flow. These strong-field control methods can be improved by targeting very specific control outcomes that exploit the unique detection capabilities of the TPX3Cam.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.