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Fred E. Wietfeldt (Assoc)

Dr. Fred Wietfeldt joined the Radiation Physics Division in 1995 as a National Research Council Postdoctoral Fellow in the Neutron Physics group at the NIST Center for Neutron Research (NCNR). In 2001 he moved to Tulane University as a faculty member and is currently Professor of Physics and Chair of the Department of Physics and Engineering Physics at Tulane. He remains a Guest Researcher at NIST and maintains research collaborations with the Neutron Physics group and the NCNR.

Dr. Wietfeldt has two main research interests: 1) precision studies of free neutron decay parameters; and 2) neutron interferometry. Most of this work is done at the NCNR in collaboration with NIST staff, along with his students and postdocs, and collaborating scientists from other institutions. Recent experiments include measurement of the electron-antineutrino correlation in neutron decay (aCORN experiment); observation and measurement of radiative neutron decay; limits on the time-reversal symmetry violating D-coefficient in neutron decay; the free neutron lifetime using the in-beam method; and precision measurements of the neutron scattering lengths of 3He and 4He using neutron interferometry.

Dr. Wietfeldt is a Fellow of the American Physical Society and a member of Sigma Xi. His research has been supported by the National Science Foundation continuously since 2003. He earned his B.S. in engineering at M.I.T. in 1984 and Ph.D. in physics at the University of California, Berkeley in 1994. He also served on active duty in the U.S. Navy as a nuclear engineering officer from 1984-1989.

Publications

Observation of the Radiative Decay Mode of the Free Neutron

Author(s)
Jeffrey S. Nico, Maynard S. Dewey, Thomas R. Gentile, Hans P. Mumm, Alan K. Thompson, B Fisher, I Kremsky, Fred E. Wietfeldt, T E. Chupp, R Cooper, E Beise, K G. Kiriluk, J Byrne, Kevin J. Coakley
The theory of quantum electrodynamics predicts that beta decay of the neutron into a proton, electron, and antineutrino should be accompanied by a continuous

Radiative Decay Mode of the Free Neutron

Author(s)
Jeffrey S. Nico, Maynard S. Dewey, Thomas R. Gentile, Hans P. Mumm, Alan K. Thompson, B M. Fisher, I Kremsky, Fred E. Wietfeldt, T E. Chupp, R L. Cooper, E J. Beise, K G. Kiriluk, J Byrne, K Coakley
Created May 23, 2019, Updated June 15, 2021