相关论文: Mirror matter admixtures in K_L \to \gamma\gamma
The latest measurement of the K_S to gamma gamma branching ratio clearly shows an enhancement over the current theoretical prediction. As in other K and B meson decays, this invites to consider the possibility of the contribution of new…
We analyze the $\gamma p \to \eta p$ process from threshold up to 1.2 GeV, employing an effective Lagrangian approach that allows for a mixing of eta couplings of pseudoscalar and pseudovector nature. The mixing ratio of the couplings may…
Although eta-eta' mixing is qualitatively well understood as a consequence of the U(1)_A anomaly in QCD together with a broken SU(3) flavor symmetry, until recently the values of decay and mixing parameters of the eta and eta' were only…
We extend our previous analysis of mirror matter admixtures to reproduce the |\Delta I|=1/2 rule predictions in the decays \Omega^-\to\Xi^-\pi^0, \Omega^-\to\Xi^0\pi^-, and \Omega^-\to\Lambda K^-. The results are satisfactory, lending…
We study symmetry breaking in a left-right symmetric extension of the Standard Model with mirror fermions, one for each Standard-Model fermion. The new particles assist a top-quark condensate in breaking electro-weak symmetry. Half of the…
A simple way to accommodate dark matter is to postulate the existence of a hidden sector. That is, a set of new particles and forces interacting with the known particles predominantly via gravity. In general this leads to a large set of…
We determine the $\eta-\eta'$ mixing angle via a procedure relatively independent of theoretical assumptions by simultaneously fitting $\eta- eta'$ reactions involving the anomaly--$\eta,\eta'\to\gamma\gamma, \pi^+\pi^-\gamma$. We extract…
An analysis is given of the decay $\mu \to e+ \gamma$ in an MSSM extension with a vectorlike generation. Here mixing with the mirrors allows the possibility of this decay. The analysis is done at the one loop level with the exchange of…
We discuss a description of \Omega^- two body non-leptonic decays based on possible, albeit tiny, admixtures of mirror matter in ordinary hadrons. The \Delta I=1/2 rule enhancement is obtained as a result of isospin symmetry and, more…
We calculate a number of observables related to particle-antiparticle mixing in the Littlest Higgs model with T-parity (LHT). The resulting effective Hamiltonian for Delta F=2 transitions agrees with the one of Hubisz et al., but our…
We have observed the decay $K_L\to \mu^+\mu^- \gamma \gamma$ at the KTeV experiment at Fermilab. This decay presents a formidable background to the search for new physics in $K_L\to\pi^0\mu^+\mu^-$. The 1997 data yielded a sample of 4…
Within the framework of the $U(3)$ chiral perturbation theory, we revisit the masses, decay constants and the mixing parameters of the light pseudoscalar mesons $\pi, K, \eta$ and $\eta'$. The low energy constants up to…
In the present paper we have developed a concept of parallel ordinary (O) and mirror (M) worlds. We have shown that in the case of a broken mirror parity (MP), the evolutions of fine structure constants in the O- and M-worlds are not…
Mirror dark matter provides a simple framework for which to explain the DAMA/Libra annual modulation signal consistently with the null results of the other direct detection experiments. The simplest possibility involves ordinary matter…
In the present talk we have developed a concept of parallel ordinary (O) and mirror (M) worlds. We have shown that in the case of a broken mirror parity (MP), the evolutions of fine structure constants in the O- and M-worlds are not…
Mirror world, a parallel hidden sector with microphysics identical to ordinary particle physics, can have several interesting phenomenological and astrophysical implications and mirror matter can be a natural candidate for dark matter in…
We reanalyze the eta-gamma and eta'-gamma transition form factors within the modified hard scattering approach on the basis of new experimental data from CLEO and L3. Our approach perfectly describes the experimental data over a wide range…
Up-to-date estimates of the cosmological parameters are presented as a result of numerical simulations of cosmic microwave background and large scale structure, considering a flat Universe in which the dark matter is made entirely or partly…
We consider an SU(3)'_c\times SU(2)'_L\times U(1)'_Y mirror sector where the field content and dimensionless couplings are a copy of the SU(3)_c\times SU(2)_L\times U(1)_Y ordinary sector. Our model also contains three gauge-singlet…
We study the properties of the light pseudoscalar mesons in a three flavor chiral quark model with nonlocal separable interactions. We concentrate on the evaluation of meson masses and decay constants, considering both the cases of Gaussian…