相关论文: Invisible widths of heavy mesons
We study the growth of density perturbations in a universe with unstable dark matter particles. The mass (m_\nu) range 30 eV < m_\nu < 10 keV with lifetimes ($t_d$) in the range 10^7 sec < t_d < 10^16 sec are considered. We calculate the…
We examine the parameter space of the purely phenomenological minimal super- symmetric standard model (MSSM), without assuming any supersymmetry breaking scheme. We find that a large region of the parameter space can indeed yield the…
In this paper, we present results on strong two-body decay widths of light $q\bar q$ mesons calculated in a covariant quark model. The model is based on the Bethe-Salpeter equation in its instantaneous approximation and has already been…
A phenomenological model of unstable particles based on uncertainty principle is discussed in quantum field approach. We show that the simplest quantum field description of mass uncertainty makes it possible to account finite width effects…
Neutrinoless double beta decay is a process of fundamental importance for particle physics. It can be mediated by light massive Majorana neutrinos (standard interpretation) or by something else (non-standard interpretations). We review its…
The ununified standard model is an extension of the standard model that contains separate electroweak gauge groups for quarks and leptons. When it was originally proposed, data allowed the new gauge bosons to be quite light. We use recent…
A new formalism is developed for the two photon production of hybrid mesons via intermediate hadronic decays. In an adiabatic and non-relativistic context with spin 1 pair creation we obtain the first absolute estimates of unmixed hybrid…
The extension of the Standard Model by right handed neutrinos with masses in the GeV range can simultaneously explain the observed neutrino masses via the seesaw mechanism and the baryon asymmetry of the universe via leptogenesis. It has…
In this work we consider the standard model extended with singlet sterile neutrinos with mass in the eV range and mixed with the active neutrinos. The active-sterile neutrino mixing renders new contributions to the invisible Z decay width…
The standard model (SM) of particle physics is spectacularly successful, yet the measured value of the muon anomalous magnetic moment $(g-2)_\mu$ deviates from SM calculations by 3.6$\sigma$. Several theoretical models attribute this to the…
We reconsider Higgs boson invisible decays into Dark Matter in the light of recent Higgs searches at the LHC. Present hints in the CMS and ATLAS data favor a non-standard Higgs boson with approximately 50% invisible branching ratio, and…
Results are presented for the two-body decays of mesons into light neutralinos and from the first complete calculation of the loop-induced decays of kaons to pions plus light neutralinos and of B mesons to kaons plus light neutralinos. The…
We study the general phenomenology of neutrinoless double beta decay in seesaw models. In particular, we focus on the dependence of the neutrinoless double beta decay rate on the mass of the extra states introduced to account for the…
A comprehensive overview of kaon decays is presented. The Standard Model predictions are discussed in detail, covering both the underlying short-distance electroweak dynamics and the important interplay of QCD at long distances. Chiral…
We obtain the width of the $\omega$ meson in dense nuclear matter by taking into account (i) the free decay of the $\omega$ into three pions, which is dominated by $\rho \pi$ mode, (ii) the processes induced by a vector-baryon interaction…
Many analyses of two-body non-leptonic decays of $D$-mesons rely on flavor SU(3) symmetry relations and fits of experimental data of decays rates to extract the universal transition amplitudes. Such fits assume that the final state mesons…
Decays of heavy mesons and of heavy hyperons are used to provide tests of the standard model and information about new mixing schemes for the $\eta$ and $\eta^{'}$ mesons. These include the two body decays $B_s \to J / \psi M$ and $B_d \to…
In Standard Model Effective Field Theory (SMEFT), invisible neutron decay arises from d = 12 operators. Adding new light particles to the field content of the SM, such as right-handed neutrinos, allows one to construct operators for…
Rare meson decays are among the most sensitive probes of both heavy and light new physics. Among them, new physics searches using kaons benefit from their small total decay widths and the availability of very large datasets. On the other…
Searching for heavy neutral gauge bosons Z', predicted in extensions of the Standard Model based on a U(1)' gauge symmetry, is one of the challenging objectives of the experiments carried out at the Large Hadron Collider. In this paper, we…