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arXiv · 2203.07050

New Constraints on Exotic Spin-Velocity-Dependent Interactions

Abstract

Experimental searches for new, "fifth" forces are attracting a lot of attention because they allow to test theoretical extensions to the standard model. Here, we report a new experimental search for possible fifth forces, specifically spin-and-velocity dependent forces, by using a K-Rb-$^{21}$Ne 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 the fifth force is measured to be $<7$\,aT. This sets new limits on coupling constants for the neutron-nucleon and proton-nucleon interactions in the range of $\ge 0.1$ m. The coupling constant limits are established to be $|g_V^n|<6.6\times 10^{-11}$ and $|g_V^p|<3.0\times 10^{-10}$, 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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Kai Wei, Wei Ji, Changbo Fu, Arne Wickenbrock, Jiancheng Fang, Victor Flambaum, Dmitry Budker. 2022-03-14. New Constraints on Exotic Spin-Velocity-Dependent Interactions. https://doi.org/10.1038/s41467-022-34924-z

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