Related papers: Width Difference in the $B_s-\bar{B_s}$ System
We present some straightforward applications of the QCD heavy quark expansion, stated in previous papers [1-3], to the inclusive widths of heavy flavour hadrons. We address the question of the $D_s$ lifetime and argue that -- barring Weak…
We analyze the theoretical uncertainties in $Br(B\to X_s\gamma)$ due to the choice of the high energy matching scale $\mu_W=\ord(\mw)$ and the scale $\mu_t$ at which the running top quark mass is defined: $\mtb(\mu_t)$. To this end we have…
We describe a theoretical approach to compute inclusive widths of heavy hadrons, based on a systematic expansion in the inverse powers of the heavy quark mass. The method reproduces quite well the experimental ratios of $B$ mesons…
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 $Z^0 \to b\bar b$ width, $\Gamma_b$, is analysed in conjunction with the total and hadronic $Z^0$ widths, $\Gamma_T$ and $\Gamma_h$. Assuming, tentatively, that the present 2$\sigma$ discrepancy in $\Gamma_b$ will substantiate as time…
We present formulae for the mass differences $\Delta M_d$ and $\Delta M_s$ in the \BBds systems and for the CP violation parameter $\epsilon$ which are valid in minimal flavour violation models giving rise to new four-fermion $\Delta F=2$…
Using the expansions of the heavy meson decay widths in the heavy quark mass and QCD sum rules for estimates of corresponding matrix elements,\, we calculate the $D^{\pm,o,s}$ decay widths and the $B^{\pm,o,s}$ lifetime differences. The…
Present experiments in pursuit of the mass difference in the Bs-Bs(bar) system have put a lower bound on this quantity of $\Delta M_s > 14.9 ps^{-1}$ (at 95% C.L.). The same experiments also yield a local minimum in the log-likelihood…
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…
We present a detailed evaluation of the total semileptonic B meson width in terms of |V_{cb}| and heavy quark parameters (quark masses and the expectation values of local heavy quark operators). Special attention is given to perturbative…
The present status of the theoretical estimates of beauty hadron lifetime ratios and of width differences and CP-violation parameters in $B_d$ and $B_s$ systems is reviewed. In the last two years accurate lattice calculations and…
Applying an operator product expansion approach we update the Standard Model prediction of the $B_c$ lifetime from over 20 years ago. The non-perturbative velocity expansion is carried out up to third order in the relative velocity of the…
We present leading logarithmic QCD corrections to the decay B_s --> \gamma\gamma in the Standard Model. Further, the form factor F_{1}(0) of B_s --> \phi\gamma is calculated in the framework of QCD sum rules and found to be in agreement…
We present predictions based on the heavy quark expansion in QCD. We find SU(3) breaking in B mesons suppressed in the framework of the HQE. B_s is expected to have the semileptonic width about 1% lower and Lambda_b about 3% higher when…
We give a review of the theoretical status of the lifetime predictions in the standard model. In case of $(\Delta \Gamma/ \Gamma)_{B_s}$ we are already in a rather advanced stage. We obtain…
CP-violating effects in non-leptonic $B_s$-meson decays are reviewed. Special emphasis is given to implications arising from the width difference $\Delta\Gamma_s$ between the $B_s$ mass eigenstates. If $\Delta\Gamma_s$ is found to be…
We investigate new physics models that can increase the lifetime differences in the $B_q$--$\bar{B}_q$ systems ($q = d,s$) above their standard model values. If both $B_q$ as well as $\bar{B}_q$ can decay to a final state through flavour…
We have recently seen new upper bounds for $B^0_s\to \mu^+\mu^-$, a key decay to search for physics beyond the Standard Model. Furthermore a non-vanishing decay width difference $\Delta\Gamma_s$ of the $B_s$ system has been measured. We…
The LHCb experiment has recently established a sizable width difference between the mass eigenstates of the $B_s$-meson system. This phenomenon leads to a subtle difference at the 10% level between the experimental branching ratios of $B_s$…
About 90% of Bs-bar Bs pairs produced at the Upsilon(5s) resonance are initially Bs*-bar Bs* pairs which decay radiatively to Bs-bar Bs. This implies that the Bs pair will then be in an eigenstate of charge conjugation (i.e. C=-1) and…