相关论文: Muon lifetime and muon capture
We study the muon anomalous magnetic moment $(g-2)_{\mu}$ in the context of the reduced minimal 3-3-1 model recently proposed in the literature. In particular, its spectrum contains a doubly charged scalar ($H^{\pm \pm}$) and gauge boson…
The TRIUMF Weak Interaction Symmetry Test (TWIST) experiment was designed to test the standard model at high precision in the purely leptonic decay of polarized muons. A general four-fermion interaction model is used to describe the muon…
A number of extensions of the Standard Model predict the existence of new light, weakly-coupled particles that couple to the visible sector through higher-dimensional operators containing one or two photons, suppressed by a high new physics…
The decays and mixing of $K$ mesons are remarkably sensitive to the weak interactions of quarks and leptons at high energies. They provide important tests of the standard model at both first and second order in the Fermi constant $G_F$ and…
The complete O(N_f alpha^2) weak contributions to the muon lifetime, denoted as Delta r^(2), are calculated in the MS-bar renormalization scheme. These come from 2-loop Feynman diagrams containing a loop formed by complete generations of…
Landau's Fermi Liquid parameters are calculated for non-superfluid pure neutron matter in the presence of a strong magnetic field at zero temperature. The particle-hole interactions in the system, where a net magnetization may be present,…
Confronted with some surprising claims about experimentally measured or theoretically expected dependencies on the involved momentum transfer of various form factors of pseudoscalar mesons, we reassess the present status of these quantities…
The new measurement of the muon's anomalous magnetic moment released by the Muon g-2 experiment at Fermilab sets strong constraints on the properties of many new particles. Using an effective field theory approach to the interactions of…
This paper presents a fast approach to simulating muons produced in interactions of the SPS proton beams with the target of the SHiP experiment. The SHiP experiment will be able to search for new long-lived particles produced in a…
Since the announcement of the muon $g-2$ measurements, numerous studies have been devoted to exploring the new physics through this precision probe. In specific models, the new physics contributions depend on the couplings and mass scales.…
The two-pion low-energy contribution to the anomalous magnetic moment of the muon, $a_\mu\equiv(g-2)_\mu/2$, expres sed as an integral over the modulus squared of the pion electromagnetic form fac tor, brings a relatively large contribution…
We examine the role of resonant coupled channel final state interactions (FSI), as well as weak annihilation and exchange contributions in explaining all the two body hadronic $D\rightarrow PP$ decay modes data. In the un-unitarized…
A new experiment at Fermilab will measure the anomalous magnetic moment of the muon with a precision of 140 parts per billion (ppb). This measurement is motivated by the results of the Brookhaven E821 experiment that were first released…
The meson (pion and kaon) form factor is calculated in the perturbative framework with alternative forms for the running coupling constant and the gluon propagator in the infrared kinematic region. These modified forms are employed to test…
In this article, we calculate the axial and the induced pseudoscalar form-factors $G_A(t=-Q^2)$ and $G_P(t=-Q^2)$ of the nucleons in the framework of the light-cone QCD sum-rules approach up to twist-6 three valence quark light-cone…
We consider a mathematical model of the Fermi theory of weak interactions as patterned according to the well-known current-current coupling of quantum electrodynamics. We focuss on the example of the decay of the muons into electrons,…
The electron and muon anomalous magnetic moments (AMM) are measured in experiments and studied in the Standard Model (SM) with the highest precision accessible in particle physics. The comparison of the measured quantity with the SM…
The present status of universality tests of the weak couplings for quarks and leptons is reviewed, with updated information for the muon lifetime and for first-row inputs in the CKM matrix. We discuss the impact of this high-precision SM…
We introduce an effective lagrangian including negative and positive parity heavy mesons containing a heavy quark, light pseudoscalars, and light vector resonances, with their allowed interactions, using heavy quark spin-flavour symmetry,…
The production of an intense, high energy and low emittance muon beam is interesting for a possible muon collider. The Low EMittance Muon Accelerator (LEMMA) team at the Istituto Nazionale di Fisica Nucleare (INFN), in Italy, is studying…