相关论文: Fifth Force and Hyperfine Splitting in Muonic Atom…
There is great interest within the particle physics community for building a $\mu^+\mu^-$ collider with center-of-mass (CoM) energies ranging from $\sqrt{s}\sim$ 1-14 TeV. For Beyond-the-Standard-Model (BSM) physics, natural supersymmetry…
Newly calculated bounds on the strength of the coupling of an electron to a proton or a neutron by a fifth force are presented. These results are derived from the high precision spectroscopic data currently available for hydrogen,…
We explore the possibility that a new interaction between muons and protons is responsible for the discrepancy between the CODATA value of the proton radius and the value deduced from the measurement of the Lamb shift in muonic hydrogen. We…
Most embeddings of the Standard Model into a more unified theory, in particular the ones based on supergravity or superstrings, predict the existence of a hidden sector of particles which have only very weak interactions with the visible…
Dark photons, hypothetical feebly interacting massive vector bosons, appear in many extensions of the Standard Model. This study investigates their production and subsequent decay during supernova explosions. We demonstrate that the decay…
Pulsars, highly magnetized, rotating neutron stars, can have significant muon abundances in their dense cores, making them promising environments to probe ultralight mediators coupled to muons. The precise measurement of periastron advance…
In this paper we survey the effects of residual long-range forces associated to $\gamma_5$-spin dependent-couplings of fermions to massless bosons exerted by unpolarised bulk matter over macroscopic distances. We establish that such forces…
Promising searches for new physics beyond the current Standard Model (SM) of particle physics are feasible through isotope-shift spectroscopy, which is sensitive to a hypothetical fifth force between the neutrons of the nucleus and the…
High-energy particle physics experiments allow for the possible existence of a new light, very weakly coupled, neutral gauge boson (the U boson). This one permits for light (spin-1/2 or spin-0) particles to be acceptable Dark Matter…
The potential of muon colliders to address fundamental physics issues is explored, with emphasis on understanding the nature of electroweak symmetry breaking. The $s$-channel production of Higgs bosons, unique to a muon collider, along with…
It has been suggested that a potentially large fraction of supernovae could be accompanied by relativistic outflows that stall below the stellar surface. In this letter we point out that internal shocks that are believed to accelerate…
The unbound proton-rich nuclei $^{16}$F and $^{15}$F are investigated experimentally and theoretically. Several experiments using the resonant elastic scattering method were performed at GANIL with radioactive beams to determine the…
There is renewed interest in studies of muonic atoms, which may provide detailed information on nuclear structure. A major limiting factor in the interpretation of measurements is the nuclear polarization contribution. We propose a method…
Only two types of Standard Model particles are able to propagate the $480\,$meters separating the ATLAS interaction point and FASER: neutrinos and muons. Furthermore, muons are copiously produced in proton collisions. We propose to use…
There are a number of observational hints from astrophysics which point to the existence of stellar energy losses beyond the ones accounted for by neutrino emission. These excessive energy losses may be explained by the existence of a new…
This article describes the dynamics of a charge particle in a electromagnetic field in presence of a scalar fifth force. Focusing to the fifth force that would be induced by a chameleon field, the profile of which can be designed properly…
The recent discrepancy between proton charge radius measurements extracted from electron-proton versus muon-proton systems is suggestive of a new force that differentiates between lepton species. We identify a class of models with gauged…
We investigate the sensitivity of future high-energy muon colliders to heavy Majorana neutrinos, considering both opposite-sign ($\mu^+\mu^-$) and same-sign ($\mu^+\mu^+$) collision modes. We focus on $\mu^+\mu^-$ colliders operating at…
We report on recent result according to which the fermion-fermion interaction mediated by axions and axion-like particles can be revealed by means of neutron interferometry. We assume that the initial neutron beam is split in two beams…
The leading-order contribution of a new boson to the muonic fine-structure anomaly, which refers to a discrepancy between the predicted transition energies and spectroscopic measurements of $\mu-^{90}$Zr, $\mu-^{120}$Sn, and $\mu-^{208}$Pb,…