Epscor research fellows: NSF: probing ultrafast photochemical dynamics with attosecond coincidence spectroscopy and high-repetition-rate pump-probe measurements

The National Science Foundation Office of Integrative Activities awarded Emporia State University $244,335 on January 1, 2027, under the Integrative Activities program (CFDA 47.083) to support an EPSCOR Research Fellows project investigating ultrafast photochemical dynamics using attosecond coincidence spectroscopy and high-repetition-rate pump-probe measurements.

The award provides a fellowship to an assistant professor at Emporia State University and training for an undergraduate student. The research, conducted in collaboration with Dr. Meng Han at Kansas State University, examines how light causes atoms and molecules to rearrange or break apart, focusing on how changes in electron density trigger these processes and how atomic motion shapes outcomes. The work combines chemistry, physics, and laser science using high-frequency laser measurements and imaging techniques on small molecule model systems.

The integrated experimental framework links high-repetition-rate pump-probe measurement using Coulomb explosion imaging with attosecond extreme-ultraviolet spectroscopy using electron-ion coincidence detection. This approach provides channel-specific and site-sensitive information connecting electronic excitation, atomic motion, and product formation. The project will advance understanding of how molecular structure governs relaxation, dissociation, and competing photochemical pathways, while developing experimental protocols, data-analysis methods, and collaborative research capabilities that strengthen atomic, molecular, and optical science at Emporia State University.

The fellowship supports advances in photosynthesis, energy conversion, and green energy storage while training early-career faculty and students in advanced experiments and interdisciplinary research. Performance occurs in Emporia, Kansas, with a period of performance from January 1, 2027, through December 31, 2028.

Abstract

This research infrastructure improvement (RII) epscor research fellows project provides a fellowship to an assistant professor and training for an undergraduate student at the emporia state university. This work is conducted in collaboration with DR. Meng HAN at kansas state university. Through the fellowship, the PI will investigate how light causes atoms and molecules to rearrange or break apart. The project will address how changes in electron density trigger these processes and how atomic motion shapes the outcome. The work combines chemistry, physics, and laser science enhancing understanding of light-driven processes using high-frequency laser measurements and imaging techniques. Studies of small molecule model systems will test this approach. The fellowship will support advances in photosynthesis, energy conversion, and green energy storage. IT will also train early-career faculty and students in advanced experiments and interdisciplinary research, strengthening the stem workforce. The project will establish an integrated framework for investigating ultrafast electronic, structural, and fragmentation dynamics in atoms and molecules. IT combines high-repetition-rate pump-probe measurement using coulomb explosion imaging and attosecond extreme-ultraviolet spectroscopy using electron-ION coincidence detection. This approach links electronic excitation, atomic motion, and product formation with channel-specific and site-sensitive information. The work will advance understanding of how molecular structure governs relaxation, dissociation, and competing photochemical pathways. The research will develop experimental protocols, data-analysis methods, and collaborative research capabilities that strengthen atomic, molecular and optical science at emporia state university. Undergraduate students will receive training in laser operations, spectroscopy, instrumentation, computational analysis, and scientific communication. Partnership with the host site will broaden access to advanced facilities, improve curriculum, and strengthen long-term research and workforce development. This project is supported by the epscor research infrastructure improvement program: epscor research fellows (ERF), which supports early- and mid-career investigators in eligible jurisdictions to develop collaborations at the nation?s private, government or academic research institutions. 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.- subawards are not planned for this award.