Dr. Axel Schmidt
Dr. Axel Schmidt
Assistant Professor of Physics; Undergraduate Advisor
Core
Contact:
Axel Schmidt has been an assistant professor at George Washington University since 2020. In his research, he uses electromagnetic probes (high energy electrons, positrons, or photons) to learn about how proton and neutrons move and interact within nuclei, or how quarks move and interact within protons and neutrons. He conducts experiments at the Thomas Jefferson National Accelerator Facility (Jefferson Lab) as well as at other accelerators around the world. He is also working to successfully realize the future Electron-Ion Collider.
Prof. Schmidt is the lead PI of GW's Jefferson Lab Group.
Prof. Schmidt conducts research into how the strong nuclear force determines the structure of protons, neutrons, and atomic nuclei, across several different distance scales. He is particularly interested in questions such as
- How do protons and neutrons form short-range correlations, and what properties do these correlated pairs exhibit?
- What are the effective forces between protons and neutrons at very short distances?
- Why do quarks behave differently when their parent proton or neutron is embedded in a nucleus?
- What are the properties of different short-lived meson and baryon particles?
- How much does two-photon exchange affect the results of electron scattering?
To answer these questions, Prof. Schmidt conducts high-energy electron scattering experiments (and occasionally photon-scattering and positron-scattering too) at particle accelerators such as the Thomas Jefferson National Accelerator Facility (JLab) in Newport News, VA as well as in Germany, at the Deutsche Elektronen Synchrotron (DESY) and at the Mainz Microtron (MAMI). He is a member of the CLAS and GlueX Collaborations at JLab.
Scattering experiments depend on sophisticated detectors to observe particles emerging from collisions. Most recently, Prof. Schmidt helped build the "Backward Angle Neutron Detector" (BAND), now deployed as part of CLAS at JLab. BAND measures the time-of-flight of neutrons emerging from deep inelastic scattering collisions on deuterium and other nuclei.
Prof. Schmidt is also a member of the EPIC Collaboration, working to design and build the primary experiment for the future Electron-Ion Collider.
Learn more at the GW Jefferson Lab Group Website.
Prof. Schmidt teaches:
- PHYS1021 - University Physics I
- PHYS2151 - Intermediate Laboratory I
- PHYS4175 - Nuclear Physics
Recent highlights (for a complete list of publications, see Inspire):
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"Search for a bound di-neutron by comparing 3He(e,e'p)d and 3H(e,e'p)X measurements," D. Nguyen et al., Phys. Lett. B 831, 137165 (2022)
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"Single-pion contribution to the Gerasimov-Drell-Hearn sum rule and related integrals," I. I. Strakovsky et al., Phys. Rev. C 105, 045202 (2022)
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"Many-body factorization and position–momentum equivalence of nuclear short-range correlations," R. Cruz-Torres et al., Nature Physics 17, pp. 306–310 (2021)
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"12C(e,e'pN) measurements of short range correlations in the tensor-to-scalar interaction transition region," I. Korover et al., Phys. Lett. B 820, 136523 (2021)
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"Target-normal single spin asymmetries measured with positrons," G. N. Grauvogel, T. Kutz, A. Schmidt, Eur. Phys. J. A 57, 213 (2021)
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"Short-range correlations and the nuclear EMC effect in deuterium and helium-3," E. P. Segarra et al., Phys. Rev. Research 3, 023240 (2021)
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"Extracting the number of short-range correlated nucleon pairs from inclusive electron scattering data," R. Weiss et al., Phys. Rev. C 103, L031301 (2021)
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"Neutron Valence Structure from Nuclear Deep Inelastic Scattering," E. P. Segarra et al., Phys. Rev. Lett. 124 092002 (2020)
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"Probing the core of the strong nuclear interaction," A. Schmidt et al., Nature, 578 pp. 540-544 (2020)
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"How much two-photon exchange is needed to resolve the proton form factor discrepancy?" A. Schmidt, J. Phys. G 47 055109 (2020)
Review Articles and Guest Editorship
- "Progress in Understanding Short-Range Structure in Nuclei: An Experimental Perspective," J. Arrington, N. Fomin, A. Schmidt, Annual Review of Nuclear and Particle Science, Vol. 72, pp. 307-337 (2022)
- "Topical issue on an experimental program with positron beams at Jefferson Lab," European Physical Journal A vol 58. (2022)
Ph.D. in Physics, Massachusetts Institute of Technology, 2016
B.S. in Physics, Yale University, 2009