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Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
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Using geoelectrons to search for velocity-dependent spin-spin interactions.
1Physics Department, Amherst College, Amherst, Massachusetts 01002, USA.
Physical Review Letters
|March 25, 2014
Summary
This study bounds long-range spin-spin interactions using a geoelectron-spin model and laboratory data. It significantly improves limits on five previously unbounded interactions and enhances the bound on a sixth by 30 orders of magnitude.
Area of Science:
- Particle Physics
- Astrophysics
- Geophysics
Background:
- Electron spins within Earth offer a unique environment to probe fundamental interactions.
- Previous laboratory experiments set limits on fermion-spin orientations relative to Earth.
Purpose of the Study:
- To investigate six possible long-range velocity-dependent spin-spin interactions.
- To constrain interactions mediated by ultralight or massless intermediate vector bosons.
Main Methods:
- Utilized a recently developed geoelectron-spin model.
- Combined data from three existing laboratory experiments.
- Applied the model to experimental results to derive bounds on spin-spin interactions.
Main Results:
- Established new upper limits for five previously unbounded spin-spin potentials.
- Improved the bound on the sixth potential by 30 orders of magnitude in the long-range limit.
- Constrained velocity-dependent interactions coupling electron spin to electron, neutron, and proton spins.
Conclusions:
- The geoelectron-spin model, combined with experimental data, provides powerful constraints on fundamental spin-spin interactions.
- This research significantly advances our understanding of potential new forces mediated by light bosons.
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