Related papers: Muonic hydrogen and MeV forces
The anomalous magnetic moment of the muon is an important observable that tests radiative corrections of all three observed local gauge forces: electromagnetic, weak and strong interactions. High precision measurements reveal some…
The performance demands of future particle-physics experiments investigating the high-energy frontier pose a number of new challenges, forcing us to find improved solutions for the detection, identification, and measurement of final-state…
The contribution of virtual excitations to the energy levels of electronic and muonic hydrogen is investigated combining a model-independent approach for the main part with quark model predictions for the remaining corrections. Precise…
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…
A new scalar boson which couples to the muon and proton can simultaneously solve the proton radius puzzle and the muon anomalous magnetic moment discrepancy. Using a variety of measurements, we constrain the mass of this scalar and its…
By using a Coulomb potential modified by the interaction between the magnetic moments of the electron and proton, we have calculated the energy levels of a hydrogen atom. We have obtained fine structure, hyperfine structure and the Lamb…
Theories beyond the standard model involving a sub-GeV-scale vector $Z_d$ mediator have been largely studied as a possible explanation of the experimental values of the muon and electron anomalous magnetic moments. Motivated by the recent…
The observed interactions between particles are not fully explained in the successful theoretical description of the standard model to date. Due to the close confinement of the bound state muonium ($M = \mu^+ e^-$) can be used as an ideal…
We point out that heavy new physics contributions in leptonic dipole moments and high-energy cross-sections of lepton pairs into Higgs bosons and photons are connected model-independently. In particular, we demonstrate that a muon collider,…
Theoretical predictions underlying determinations of the fine structure constant alpha and the electron-to-proton mass ratio m_e/m_p are reviewed, with the emphasis on the bound electron magnetic anomaly g-2. The theory of the interaction…
We constrain the possibility of a new pseudoscalar coupling between the muon and proton using a recent measurement of the 2S hyperfine splitting in muonic hydrogen.
The recent observation of discrepancies in the muonic sector motivates searches for the yet undiscovered atom true muonium $(\mu^+\mu^-)$. To leverage potential experimental signals, precise theoretical calculations are required. I will…
The QED hadronic vacuum polarization function plays an important role in the determination of precision electroweak observables and of the anomalous magnetic moment of the muon. These contributions have been computed from data, by means of…
We explore the response to energetic partons of a baryon-charged medium produced in low energy heavy-ion collisions in which the partonic energy loss rate is expected to depend on both temperature and baryon chemical potential. The energy…
The SND@LHC experiment investigates neutrinos in the forward pseudorapidity range of $7.2 < \eta < 8.4$. The detector consists of a veto system, a scintillating fiber (SciFi) tracker interleaved with emulsion cloud chambers (ECCs), and a…
On the analogy with the Lamb shift, we study the vacuum effect that proton's electric field interacts with virtual particles in the vacuum. We find a possible quantum instability that triggered by an external force, proton's electric field…
The average transverse momentum dependence on multiplicity shows in many experiments at center of mass energies ranging from 22 to 7000 GeV a slope change at a charged particle rapidity density constant within systematic uncertainties. We…
In the paper Int.J.Mod.Phys.E 23 (2014) 1450004, the potential of short-baseline experiments was proposed to measure the mass (and parameters of Lorentz-violating effects) of the muon neutrino, where a roughly estimated upper bound of 420…
The hadronic vacuum polarization (HVP) contributions to the muon $g$$-$$2$ are the crucial quantity to resolve whether new physics is present or not in the comparison between the Standard Model (SM) prediction and experimental measurements…
The discrepancy between the muon $g-2$ measurement and the Standard Model prediction points to new physics around or below the weak scale. It is tantalizing to consider the loop effects of a heavy axion (in the general sense, also known as…