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Electromagnetic Backgrounds and Angular-Momentum Barriers in Gravitomagnetic Searches with Hydrogen-Like Ions
arXiv:2604.20717v2 Announce Type: replace Abstract: Hydrogen-like ions cannot usefully bound the gyrogravitational ratio $\chi$: in ${}^{95}$Mo$^{41+}$ gravity shifts the hyperfine constants by fractions of $10^{-39}$--$10^{-38}$ with the tensor structure of the hyperfine interaction, centroids cancel it, and the $2p$ lines are 1.3 eV wide. Isotopes with spin can, however, enter the King plots that search for new bosons: for the cadmium clock line, the second-order hyperfine shift of ${}^{111}$Cd is $-0.96$~MHz, and a specific difference with ${}^{113}$Cd reduces it to about $2$~Hz after calculable anomaly and third-order corrections.
Abstract:Hydrogen-like ions cannot usefully bound the gyrogravitational ratio $\chi$: in ${}^{95}$Mo$^{41+}$ gravity shifts the hyperfine constants by fractions of $10^{-39}$--$10^{-38}$ with the tensor structure of the hyperfine interaction, centroids cancel it, and the $2p$ lines are 1.3 eV wide. Isotopes with spin can, however, enter the King plots that search for new bosons: for the cadmium clock line, the second-order hyperfine shift of ${}^{111}$Cd is $-0.96$~MHz, and a specific difference with ${}^{113}$Cd reduces it to about $2$~Hz after calculable anomaly and third-order corrections.
4 pages, 1 figure, 1 table, plus 9 pages of Supplemental Material. Substantially revised version. The spin-quadrupole shift and the projected laboratory bound of v1 are withdrawn: hydrogen-like ions cannot usefully test the gravitational coupling of nuclear spin. New: use of isotopes with spin in King plots, with a CI+MBPT calculation for the cadmium clock line
arXiv:2604.20717 [quant-ph]
(or arXiv:2604.20717v2 [quant-ph] for this version)
Full text under the publisher's open licence · 147 words