The normalized elimination of the small component (NESC) method is a Dirac-exact relativistic method that leads to reliable first order response properties such as contact densities, Mössbauer shifts, electric field gradients, quadrupole coupling constants, or hyperfine structure constants for heavy atoms. In this review, the calculation of these hyperfine parameters with a NESC analytical deri...

We present a consistent way of describing heavy baryons containing a heavy quark as bound states of an SU(2) soliton and heavy mesons. The resulting mass formula reveals the heavy quark symmetry explicitly. By extending the model to the orbitally excited states, we establish the generic structure of the heavy baryon spectrum. As anticipated from the heavy quark spin symmetry, the c-factor denot...

We consider the proton structure corrections to hydrogen ground-state hyperfine structure, focusing on a state-of-the-art evaluation of the inelastic nucleon corrections—the polarizability corrections—using analytic fits to the most recent data. We find a value for the fractional correction ∆pol of 1.3 ± 0.3 ppm. This is 1–2 ppm smaller than the value of ∆pol one would deduce using hyperfine sp...

Recent advances in interpreting the most accurate to-date measurement of atomic parity violation in Cs are reviewed. The inferred nuclear weak charge, QW ( Cs) = −72.65(28)expt(36)theor, agrees with the prediction of the standard model at 1σ level. Further improved interpretation is limited by an accuracy of solving basic correlation problem of atomic structure. We report on our progress in sol...

Recent advances in interpreting the most accurate to-date measurement of atomic parity violation in Cs are reviewed. The inferred nuclear weak charge, QW ( Cs) = −72.65(28)expt(36)theor, agrees with the prediction of the standard model at 1σ level. Further improved interpretation is limited by an accuracy of solving basic correlation problem of atomic structure. We report on our progress in sol...