Related papers: Proton radius puzzle and quantum gravity at the Fe…

The sixth-order electron-loop vacuum-polarization contribution to the $2P_{1/2} - 2S_{1/2}$ Lamb shift of the muonic hydrogen ($\mu^{-} p^+$ bound state) has been evaluated numerically. Our result is 0.007608(1) meV. This eliminates the…

The standard definition of the electromagnetic radius of a charged particle (in particular the proton) is ambiguous once electromagnetic corrections are considered. We argue that a natural definition can be given within an effective field…

Measuring the 2S-2P Lamb shift in a hydrogen-like muonic atom allows one to extract its nuclear charge radius with a high precision that is limited by the uncertainty in the nuclear structure corrections. The charge radius of the proton…

From the comparison between the experimental and theoretical results for the energy difference between 2s1/2 and 2p1/2 states in hydrogen and hydrogen-like ions with different values of Z, we estimate bounds for the presence of an extra…

We argue that the proton charge radius conundrum can be resolved by weakening the assumption of perturbative formulation of quantum electrodynamics within the proton

The FAMU (Fisica degli Atomi Muonici) experiment has the goal to measure precisely the proton Zemach radius, thus contributing to the solution of the so-called proton radius puzzle. To this aim, it makes use of a high-intensity pulsed muon…

The recent conundrum with the proton charge radius inspires reconsideration of the corrections that enter into determinations of the proton size. We study the two-photon proton-structure corrections, with special consideration of the…

The relationship between the electric form factors for the proton in the rest frame and in the Breit momentum frame is used to provide a value for the difference in the mean squared charge radius of the proton evaluated in the two frames.…

The status of the proton radius puzzle (as of the date of the Confer- ence) is reviewed. The most likely potential theoretical and experimental explanations are discussed. Either the electronic hydrogen experiments were not sufficiently…

The proton structure and proton polarizability corrections to the Lamb shift of electronic hydrogen and muonic hydrogen were evaluated on the basis of modern experimental data on deep inelastic structure functions. Numerical value of proton…

Laser spectroscopy of muonic atoms has been recently used to probe properties of light nuclei with unprecedented precision. We introduce nuclear effects in hydrogen-like atoms, nucleon structure quantities (form factors, structure…

We show that off-mass-shell effects arising from the internal structure of the proton provide a new proton polarization mechanism in the Lamb shift, proportional to the lepton mass to the fourth power. This effect is capable of resolving…

The deuteron charge radius is calculated from the measurement of the Lamb shift in muonic deuterium, taking into account the electron vacuum polarization correction to the nuclear-structure effects. This correction is unexpectedly large and…

Weak interaction contributions to hyperfine splitting and Lamb shift in light electronic and muonic atoms are calculated. We notice that correction to hyperfine splitting turns into zero for deuterium. Weak correction to the Lamb shift in…

The proton radius conundrum [R. Pohl et al., Nature vol.466, p.213 (2010) and A. Antognini et al., Science vol.339, p.417 (2013)] highlights the need to revisit any conceivable sources of electron-muon nonuniversality in lepton-proton…

Laser spectroscopy of the Lamb shift (2S-2P energy difference) in light muonic atoms or ions, in which one negative muon $\mu^-$ is bound to a nucleus, has been performed. The measurements yield significantly improved values of the…

The proton structure effects, including finite size, polarizability and self-energy is considered and their influence on energy levels of muonic hydrogen is recalculated. A new theoretical prediction for the Lamb shift is presented together…

We show that the value of the proton mass depends on each bound state of muonic or electronic hydrogen atom. The charged particle bound to the proton produces magnetic field inside the proton. This makes a change to the amount of chiral…

Proton structure effects in hydrogenic bound states are analyzed using nonrelativistic QED effective field theory. Implications for the Lamb shift in muonic hydrogen are discussed. Model-dependent assumptions in previous analyses are…

To shed light on the deuteron radius puzzle we analyze the theoretical uncertainties of the nuclear structure corrections to the Lamb shift in muonic deuterium. We find that the discrepancy between the calculated two-photon exchange…