相关论文: Lifetime Difference in B_s mixing: Standard Model …

Recent measurements of lifetimes of some $b$-flavored hadrons are presented and interpreted in the context of theoretical models, especially the Heavy Quark Expansion. Decay widths and decay width differences in the $B_s^0-\overline{B}_s^0$…

A simple relativistic model of heavy-light mesons is applied to the rare decay B -> K* gamma in the standard model. We find Gamma(B -> K* gamma)/Gamma(b -> s gamma)=(17 \pm 4)% and BR(B -> K* gamma)=(4.8 \pm 1.9) \times 10^{-5}(V_cb/.04)^2.…

To reduce the current theory uncertainties a novel way to determine the $B_c$ lifetime, $\tau_{B_c}$, is proposed. Taking the difference of the $B_c$, and $B$ and $D$ meson decay rates eliminates the leading contributions from the…

A new class of enhanced non-perturbative corrections to the inclusive B->X_s+gamma decay rate is identified, which contribute first at order Lambda/m_b in the heavy-quark expansion and cannot be described using a local operator product…

In the large $N_c$ limit, the nonleptonic width of the B meson is determined by the lepton mass spectrum in semileptonic B decay and the hadron mass spectrum in $\tau$ decay. This result can be compared with the nonleptonic width computed…

Although the B(s) and Lambda(b) hadrons differ only in the spectator quarks from the well-studied B(d) and B(u) mesons, they provide a unique window on the physics of the b-quark. With no experiments presently running at the Z pole, hadron…

We complete the calculation of the element $\Gamma_{12}^q$ of the decay matrix in $B_q-\bar{B}_q$ mixing, $q=d,s$, to order $\alpha_s$ in the leading power of the Heavy Quark Expansion. To this end we compute one- and two-loop contributions…

The rare decays $B_{s(d)} \to \mu^+\mu^-$ play a key role for the testing of the Standard Model. An overview of the most recent theoretical predictions of the corresponding branching ratios is given, emphasizing that the sizable decay width…

The lifetime of the Bs0 meson is measured using the semileptonic decay Bs0 --> Ds- l+ nu X. The data sample consists of about 110 pb^-1 of pp= collisions at sqrt{s} = 1.8 TeV collected by the CDF detector at Fermilab. Four different Ds-…

We compute the matrix element of the four-quark operator $\Op_S$ = $\bar{b}(1-\gamma_5) s \bar{b} (1-\gamma_5) s$ in the $B_s-\bar{B}_s$ mixing on the lattice using NRQCD, which gives a leading contribution in the calculation of the width…

We investigate the total inclusive decay rate of the (ground state) $B_c$ meson within the framework of an operator product expansion in inverse powers of the heavy quark masses and subsequent matching onto nonrelativistic QCD. The…

Heavy quark expansion can nicely explain the lifetime of $\Lambda_{b}$. However, there still exist sizable uncertainties from the four-quark operator matrix elements of $\Lambda_{b}$ in $1/m_{b}^{3}$ corrections, which describe the…

We extract the matrix elements of four quark operators O_{L,S} relevant to the B_s and \bar B_s life time difference from QCD sum rules. We find the vacuum saturation approximation works reasonably well, i.e., within 10%. We discuss the…

The rare inclusive decay $\bar{B}\rightarrow X_s\gamma$ is an important probe of physics beyond the standard model. The largest uncertainty on the decay rate and CP asymmetry comes from operators that appear at order $1/m_b$ in the heavy…

In a recently proposed extension of the Standard Model with a compact extra dimension of size R we compute the leading corrections, of relative order (m_t R)^2, to the Branching Ratio B -> X_s gamma. For 1/R = 370 \pm 80 GeV, the branching…

We estimate $\dg/\Gamma_d$, including $1/m_b$ contributions and part of the next-to-leading order QCD corrections. We find that adding the latter corrections decreases the value of $\dg/\Gamma_d$ computed at the leading order by a factor of…

We study indirect CPT violating effects in B_d meson decays and mixing, taking into account the recent constraints on the CPT violating parameters from the Belle collaboration. The life time difference of the B_d meson mass eigenstates,…

The D^0 mixing parameter y = Delta Gamma/2 Gamma was determined by measuring the D^0 lifetime separately for the K^-pi^+ decay mode and the K^-K^+ decay mode with 12.4 fb^{-1} of data collected by the BABAR experiment in 2001. Backgrounds…

We analyze the double radiative B-meson decays B_s -> gamma gamma and B_d -> gamma gamma in QCD factorization based on the heavy-quark limit m_b >> Lambda_QCD. We systematically discuss the various contributions to these exclusive…

We consider isospin predictions for the semi-leptonic and non-leptonic decays of the $\Lambda_b$ baryon. Isospin conservation of the strong interactions constrains the possible final states in $\Lambda_b$ decays. Since the baryon hyperfine…