Related papers: On the model dependence of measured Bs-meson branc…
We have just entered an era of precision measurements for $B_s$-decay observables. A characteristic feature of the $B_s$-meson system is $B^0_s$--$\bar B^0_s$ mixing, which exhibits a sizable decay width difference. The latter feature leads…
The experimentally established non-zero decay width difference of the B_s meson system gives us access to a mass eigenstate rate asymmetry for each B_s transition. This observable is not only the key ingredient in converting between…
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 $B_s$…
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 B_s to mu+ mu- decay plays an outstanding role in tests of the Standard Model and physics beyond it. The LHCb collaboration has recently reported the first evidence for this decay at the 3.5 sigma level, with a branching ratio in the…
As is well known, $B^0_{d,s}$--$\bar B^0_{d,s}$ mixing offers a profound probe into the effects of physics beyond the Standard Model. The data obtained at the $e^+e^-$ $B$ factories have already provided valuable insights into the…
The approximate symmetry of the strong interactions under isospin transformations is among the most precise tools available to control hadronic matrix elements. It is crucial in extracting fundamental parameters, but also provides avenues…
There are several anomalous measurements in the decays induced by the quark level transition $b \to s \mu^+ \mu^-$, which do not agree with the predictions of the Standard Model. These measurements could be considered as signatures of…
The rare decay $B^0_s \to \mu^+\mu^-$ plays a key role for the testing of the Standard Model. It is pointed out that the sizable decay width difference $\Delta\Gamma_s$ of the $B_s$-meson system affects this channel in a subtle way. As a…
Measurements of the effective lifetimes of $B_s$-meson decays, which only require untagged rate analyses, allow us to probe the width difference $\Delta\Gamma_s$ and the CP-violating phase $\phi_s$ of $B^0_s$-$\bar B^0_s$ mixing. We point…
A width difference of the order of 20\% has previously been predicted for the two mass eigenstates of the $B_s$ meson. The dominant contributor to the width difference is the $b\rightarrow c\bar c s$ transition, with final states common to…
Recent measurements of the branching fraction for D_s -> l nu disagree with the Standard Model by around 2sigma. In this case the key aspect of the Standard Model is the calculation of the decay constant, f_{D_s}, with lattice QCD. This…
New physics effects on the $B^0-\bar{B}^0$ mixing and B-decay amplitudes are discussed. By a combined analysis, the model of new physics can be partially distinguished.It is emphasized that the extraction of unitarity angles $\beta$ and…
Within the perturbative QCD (PQCD) framework, we present a systematic investigation of charmless $B_s \to SP$ decays, where $S$ and $P$ denote scalar and pseudoscalar mesons, respectively. By employing two distinct structural scenarios for…
Recent measurements of the time-dependent CP asymmetry of the B -> phi K_S decay give results whose central values differ from standard model expectations. It is shown how such data can be used to identify new physics contributions in a…
This note discusses the matter of probing Beyond the Standard Model physics and how, to succeed in this quest, the interpretations of the Standard Model regarding observed phenomena must be utilized with caution. We give several specific…
We report improved measurements of branching fractions for charmless hadronic two-body {\it B} meson decays containing an $\omega$ meson in the final state. The results are based on a data sample of 78 fb$^{-1}$ collected on the…
As an alternative to direct measurements, we extract exclusive branching fractions of semileptonic B-meson decays to charmed mesons, $BF_i(B\to X_c^il\nu)$ with $X_c^i = D, D^*, D_0, D'_1, D_1, D_2, D', D'^*$ and non-resonant final states…
We provide a comprehensive model-independent analysis of rare decays involving the b --> s transition to put constraints on dimension-six Delta(F)=1 effective operators. The constraints are derived from all the available up-to-date…
We measure the branching fractions for seven $D_{s}^{+}$ two-body decays to pseudo-scalar mesons, by analyzing data collected at $\sqrt{s}=4.178\sim4.226$ GeV with the BESIII detector at the BEPCII collider. The branching fractions are…