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Updated: May 1, 2026

Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
Using geoelectrons to search for velocity-dependent spin-spin interactions
1Physics Department, Amherst College, Amherst, Massachusetts 01002, USA.
Abstract:
We use the recently developed model of the electron spins within Earth to investigate all of the six possible long-range velocity-dependent spin-spin interactions associated with the exchange of an ultralight (mz'<10(-10) eV) or massless intermediate vector boson. Several laboratory experiments have established upper limits on the energy associated with various fermion-spin orientations relative to Earth. We combine the results from three of these experiments with the geoelectron-spin model to obtain bounds on the velocity-dependent interactions that couple electron spin to the spins of electrons, neutrons, and protons. Five of the six possible potentials investigated were previously unbounded. In the long-range limit we have improved the bound on the sixth potential by 30 orders of magnitude.
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