HFS interval of the $2s$ state of hydrogen-like atoms and a constraint on a pseudovector boson with mass below $1$keV$/c^2$

Abstract

A constraint on a long-range spin-dependent interaction ${\alpha }^{\prime \prime }({\mathbf{s}}_1\cdot {\mathbf{s}}_2){\mathrm{e}}^{-\lambda r}/r$, which can be induced by a pseudovector light boson, is presented. We study theoretical and experimental data on a specific difference $8\times E_{\mathrm{hfs}}(2s)-E_{\mathrm{hfs}}(1s)$ for light two-body atoms. The spin-dependent coupling constant ${\alpha }^{\prime \prime }$ of electron-nucleus interaction in hydrogen, deuterium and helium-3 ion is constrained at the level below a part in $10^{16}$. The derived constraints are related to the range of masses below $4\mathrm{keV}/c^2$.

Comments: Cross references to Arxiv are updated (arXiv:1005.4859, arXiv:1005.4868)