Revisiting the helium isotope-shift puzzle with improved uncertainties from nuclear structure corrections

Abstract

Measurements of the difference between the squared charge radii of the helion (${}^3$He nucleus) and the $\alpha$-particle (${}^4$He nucleus) have been characterized by longstanding tensions, recently spotlighted in the 3.6 $\sigma$ discrepancy of the extractions from ordinary atoms versus those from muonic atoms. Here, we present a novel analysis of uncertainties in nuclear structure corrections that must be supplied by theory to enable the extraction of the difference in radii from spectroscopic experiments. We use modern Bayesian inference techniques to quantify uncertainties stemming from the truncation of the chiral effective field theory expansion of the nuclear force for both muonic and ordinary atoms. With the new nuclear structure input, the helium isotope-shift puzzle cannot be explained, rather it is reinforced to a 4 $\sigma$ discrepancy.

5 pages, 3 figures, 2 tables

References in corpus (16)

• Chiral effective field theory and nuclear forces
• Local three-nucleon interaction from chiral effective field theory
• Local chiral effective field theory interactions and quantum Monte Carlo applications
• Frequency metrology of helium around 1083 nm and determination of the nuclear charge radius
• Quantum Monte Carlo calculations of light nuclei with local chiral two- and three-nucleon interactions
• The proton structure in and out of muonic hydrogen
• Complete ${\alpha }^{7}m$ Lamb shift of helium triplet states
• Comprehensive theory of the Lamb shift in light muonic atoms
• Nuclear structure effects in light muonic atoms
• Improved estimates of the nuclear structure corrections in $\mu$D
• Zemach moments of 3He and 4He
• Higher-order recoil corrections for singlet states of the helium atom
• An efficient method for evaluating energy-dependent sum rules
• Uncertainty quantification in electromagnetic observables of nuclei
• Bayesian analysis of nuclear polarizability corrections to the Lamb shift of muonic H-atoms and He-ions
• Spectral function for ${}^4$He using the Chebyshev expansion in coupled-cluster theory

Cited by in corpus (5)

• Revised ${}^3$He nuclear charge radius due to electronic hyperfine mixing
• The nuclear charge radius of ${}^{13}\mathrm{C}$
• Structure and dynamics of open-shell nuclei from spherical coupled-cluster theory
• Deformation, halo, and bubble structure: A paradigm shift of exotic phenomena in light to medium mass nuclei
• Quantum science with arrays of metastable helium-3 atoms