相关论文: Muonium spectrum beyond the nonrelativistic limit

We calculate the sensitivity of the inversion spectrum of ammonia to possible time-variation of the ratio of the proton mass to the electron mass, mu=m_p/m_e. For the inversion transition (lambda= 1.25 cm^{-1}) the relative frequency shift…

The true muonium $(\mu\bar{\mu})$ bound state presents an interesting test of light-cone quantization techniques. In addition to exhibiting the standard problems of handling non-perturbative calculations, true muonium requires correct…

Since long-lived light bottom squark (sbottom) and its anti-particle with a mass close to the bottom quark have not been excluded by experiments so far, we consider such a sbottom to combine with its anti-particle to form a color singlet…

In a generic Grand Unified Theory with a relatively small dispersion of the spectrum around the $Z$-boson and the unification masses, a connection is established, exact at one loop level, between $M_Z$, $G_{\rm F}$, $\alpha(M_Z)$ and the…

We present an \emph{ab-initio} approach for computing the photoionization spectrum near autoionization resonances in multi-electron systems. While traditional (Hermitian) theories typically require computing the continuum states, which are…

O(\alpha^2 \ln(m_\mu/m_e)) corrections to electron energy spectrum in muon decay are computed using perturbative fragmentation function approach. The magnitude of these corrections is comparable to anticipated precision of the TWIST…

The variational method, within the Hamiltonian formalism of reformulated QED is used to determine relativistic wave equations for a system of three fermions of arbitrary mass interacting electromagnetically. The interaction kernels of the…

Relativistic light-front bound-state equations for mesons and baryons can be constructed in the chiral limit from the supercharges of a superconformal algebra which connect baryon and meson spectra. Quark masses break the conformal…

We use atomic spectra to extend pure Coulomb's law tests to larger masses. We interpret these results in terms of constraints for hidden sector photons. With existing data the bounds for hidden photons are not improved. However we find that…

The recently established generalized Gell-Mann--Low theorem is applied in lowest perturbative order to bound-state calculations in a simple scalar field theory with cubic couplings. The approach via the generalized Gell-Mann--Low Theorem…

A new result from searching for muonium to antimuonium conversion is reported which sets an upper limit on the coupling constant in an assumed $(V-A) \times (V-A)$ type interaction of $G_{M\bar{M}} \leq 3\cdot 10^{-3} G_F$ ~ (90% C.L.). A…

We investigate the unequal mass relativistic bound state system, the $B_c$ mesons, in a light-front Hamiltonian formalism. We adopt an effective Hamiltonian based on soft-wall light-front holography, together with a longitudinal confinement…

In this short note we resort to the well known Hellmann-Feynman theorem to prove that some non-relativistic Hamiltonian operators support an infinite number of bound states.

If the discrepancy between the theoretical and newly measured values of the muon's anomalous magnetic moment is ascribed to muon substructure, there results an improved model--independent limit on its energy scale, 1.2 TeV < Lambda_mu < 3.2…

We compute the complete O(alpha^2) QED corrections to the electron energy spectrum in unpolarized muon decay, including the full dependence on the electron mass. Our calculation reduces the theoretical uncertainty on the electron energy…

The low-energy amplitude of Compton scattering on the bound state of two charged particles of arbitrary masses, charges and spins is calculated. A case in which the bound state exists due to electromagnetic interaction (QED) is considered.…

Applying Discretized Light Cone Quantization, we perform the first calculation of the spectrum of true muonium, the $\mu^+ \mu^-$ atom, as modified by the inclusion of an $|e\bar e >$ Fock component. The shift in the mass eigenvalue is…

Relativistic electrons, seen in the large diffuse radio halo of the Coma cluster of galaxies, should scatter background photons to higher energies. We calculate the inverse Compton contributions from the microwave background, from the local…

A new upper limit for the probability of spontaneous muonium to antimuonium conversion was established at ${\rm P_{M\bar{M}}} \leq 8.2 \cdot 10^{-11}$ (90%C.L.) in 0.1~T magnetic field, which implies consequences for speculative extensions…

This is the second of a series of papers on the radiative corrections of order $\alpha^2 (Z\alpha)$, $\alpha (Z\alpha )^2$, and various logarithmic terms of order $\alpha^4$, to the hyperfine structure of the muonium ground state. This…