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Precision Measurement of Fundamental Constants Using GAMS4



Maynard S. Dewey, Ernest G. Kessler


We discuss the connection of high-energy gamma-ray measurements with precision atomic mass determinations. These rather different technologies, properly combined, are shown to lead to new values for the neutron mass and the molar Planck constant. We then proceed to describe the gamma-ray measurement process using the GAMS4 facility at the Institut Laue Langevin and its application to a recent measurement of the 2.2 MeV deutron binding energy and the neutron mass. Our report concludes by describing the first crystal diffraction measurement of the 8.6 MeV 36Cl binding energy.
Journal of Research (NIST JRES) -
105 No. 1


atomic masses, binding energy, crystal diffraction, fundamental constants, gamma rays, molar Planck constant, neutron mass


Dewey, M. and Kessler, E. (2000), Precision Measurement of Fundamental Constants Using GAMS4, Journal of Research (NIST JRES), National Institute of Standards and Technology, Gaithersburg, MD (Accessed June 21, 2024)


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Created April 1, 2000, Updated February 17, 2017