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Hans Pieter Mumm

My research interests focus on testing the Standard Model of particle physics through precision measurement. Recent examples include a test of time-reversal invariance in neutron beta decay that shed light on the matter-anitmatter asymmetry of the universe, a first observation of neutron radiative decay, and a precision measurement of the neutron lifetime using a fundamentally new technique.

During the last several years I have become interested in anomalies associated with the flux and spectral shape of antineutrinos from nuclear reactors. These anomalies either point toward problems with the nuclear physics calculations of the expected neutrino flux, or, intriguingly the possible existence of a new particle, a so-called sterile neutrino. I am currently co-spokeperson for the PROSPECT experiment which expects to make a high precision spectrum measurement and test the sterile neutrino hypothesis to high significance. In related work, I am involved in efforts to detect reactor antineutrinos with compact portable detectors for safeguards and monitoring purposes.

Finally, I am involved in efforts to improve fast neutron spectroscopy technology.


Professional Affiliations

  • Member American Physical Society (Division of Nuclear Physics, Topical Group on Precision Measurements, Fundamental Constants and Particles and Fields)
  • University of Maryland Adjunct Associate Professor of Physics


Non-fuel Antineutrino Contributions in the High Flux Isotope Reactor

PROSPECT COLLABORATION, Jerome J. LaRosa, Hans P. Mumm, Svetlana Nour, Mark A. Tyra, Denis E. Bergeron
Reactor neutrino experiments have seen major improvements in precision in recent years. With the experimental uncertainties starting to surpass those from

Experimental Upper Bound and Theoretical Expectations for Parity-Violating Neutron Spin Rotation in He-4

Jeffrey S. Nico, Hans P. Mumm, H E. Swanson, C. D. Bass, T. D. Bass, J M. Dawkins, J C. Horton, D Luo, William M. Snow, S. C. Walbridge, B. E. Crawford, K. F. Gan, A M. Micherdzinska, C. R. Huffer, D M. Markoff, Murad Sarsour, E I. Sharapov, V Zhumabekova, Blayne R. Heckel
Neutron spin rotation is expected from quark-quark weak interactions in the Standard Model, which induce weak interactions among nucleons that violate parity
Created October 9, 2019, Updated July 16, 2020