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Updated: Aug 19, 2025

Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Constraints on exotic spin-velocity-dependent interactions
Kai Wei1,2,3, Wei Ji4,5, Changbo Fu6
1School of Instrumentation Science and Opto-electronics Engineering, Beihang University, 100191, Beijing, China.
Abstract:
Experimental searches for exotic spin-dependent forces are attracting a lot of attention because they allow to test theoretical extensions to the standard model. Here, we report an experimental search for possible exotic spin-dependent force, specifically spin-and-velocity-dependent forces, by using a K-Rb-21Ne co-magnetometer and a tungsten ring featuring a high nucleon density. Taking advantage of the high sensitivity of the co-magnetometer, the pseudomagnetic field from this exotic force is measured to be ≤7 aT. This sets limits on coupling constants for the neutron-nucleon and proton-nucleon interactions in the range of ≥0.1 m (mediator boson mass ≤2 μeV). The coupling constant limits are established to be [Formula: see text] and [Formula: see text], which are more than one order of magnitude tighter than astronomical and cosmological limits on the coupling between the new gauge boson such as Z' and standard model particles.
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