Viscous Modified Cosmic Chaplygin Gas Cosmology

In this paper we construct modified cosmic Chaplygin gas which has viscosity. We use exponential function method to solve non-linear equation and obtain time-dependent dark energy density. Then discuss Hubble expansion parameter and scale factor and fix them by using observational data. We also investigate stability of this theory

Study of Bc+B^+_c decays to the K+K−π+K^+K^-\pi^+ final state by using Bs0B^0_s, χc0\chi_{c0} and D0D^0 resonances and weak annihilation nonresonant topologys

In this research the weak decay of $B^+_c$ decays to the $K^+K^-\pi^+$ final state, which is observed by LHCb collaboration for the first time, is calculated in the quasi-two-body decays which takes into account the $B^0_s$, $\chi_{c0}$ and $D^0$ resonances and weak annihilation nonresonant contributions. In this process, the $B^+_c$ meson decays first into $B^0_s\pi^+$, $\chi_{c0}\pi^+$ and $D^0\pi^+$ intermediate states, and then the $B^0_s$, $\chi_{c0}$ and $D^0$ resonances decay into $K^+K^-$ components, which undergo final state interaction. The mode of the $B^+_c\rightarrow D^0(\rightarrow K^-\pi^+)K^+$ is also associated to the calculation, in this mode the intermediate resonance $D^0$ decays to the $K^-\pi^+$ final mesons. The resonances $B^0_s$, $\chi_{c0}$ and $D^0$ effects in the $B^+_c\rightarrow B^0_s(\rightarrow K^+K^-)\pi^+$, $B^+_c\rightarrow \chi_{c0}(\rightarrow K^+K^-)\pi^+$ and $B^+_c\rightarrow D^0(\rightarrow K^+K^-)\pi^+, D^0(\rightarrow K^-\pi^+)K^+$ decays are described in terms of the quasi-two-body modes. There is a weak annihilation nonresonant contribution in which $B^+_c$ decays to the $K^+K^-\pi^+$ directly, so the point-like 3-body matrix element $\langle K^+K^-\pi^+|u\bar{d}|0\rangle$ is also considered. The decay mode of the $B^+_c\rightarrow \bar{K}^{*0}(892)K^+$ is contributed to the annihilation contribution. The branching ratios of quasi-two-body decays expand in the range from $1.98\times10^{-6}$ to $7.32\times10^{-6}$

Estimating the branching fraction for B0→ψ(2S)π0B^0\rightarrow \psi(2S)\pi^0 decay

I present estimates of the branching fractions in the non-leptonic charmonium two-body decay rates for $B^0\rightarrow \psi(2S)\pi^0$ decay and the same decays of $B^+\rightarrow \psi(2S)\pi^+$, $B^0\rightarrow \psi(2S)K^0$ and $B^+\rightarrow \psi(2S)K^+$. These estimates are based on a generalized factorization approach making use of leading order (LO) and next-to-leading order (NLO) contributions. I find that when the large enhancements from the known NLO contributions by using the QCD factorization approach are taken into account, the branching ratios are the following: $Br(B^0\rightarrow \psi(2S)\pi^0)=(1.067\pm0.059)\times10^{-5}$, $Br(B^+\rightarrow \psi(2S)\pi^+)=(2.134\pm0.0.118)\times10^{-5}$, $Br(B^0\rightarrow \psi(2S)K^0)=(6.344\pm0.376)\times10^{-4}$ and $Br(B^+\rightarrow \psi(2S)K^+)=(6.344\pm0.376)\times10^{-4}$, while the experimental results are $(1.17\pm 0.17)\times 10^{-5}$, $(2.44\pm 0.30)\times 10^{-5}$, $(6.20\pm 0.50)\times 10^{-4}$ and $(6.39\pm 0.33)\times 10^{-4}$ respectively. All estimates are in good agreement with the experimental results

The Haldane bosonisation scheme and metallic states of interacting fermions in d spatial dimensions

We consider the Haldane bosonisation scheme in d spatial dimensions as applied to a realistic model of interacting fermions in d=2 and unequivocally demonstrate failure of this scheme in d > 1, specifically in d=2. In addition to tracing back this failure to its origin, we show that {\sl nothing} as regards the true metallic state of the model under consideration is known with any degree of certainty.Comment: 20 pages, no figure