Related papers: Signals of New Physics using angular analysis in B…
We propose to investigate the effects of new physics in the semi-leptonic sequential decay $\Lambda_b \to \Lambda_c (\to \Lambda \pi) \tau{\bar \nu}_{\tau}$. Firstly, we write the general, model independent, non-covariant expression of the…
New physics (NP) in charmless strangeness-changing $B$ and $B_s$ decays, which are dominated by the $b \to s$ penguin amplitudes, can either preserve isospin or change it by one unit. A general formalism is presented studying pairs of…
Precision measurements of neutron decay offer complementary access to particle physics at small distance scales or high energies. In particular they allow tests of the V-A structure of the weak interaction. Among many experimental…
In this paper we present a feasibility study for measuring the combination of the Unitarity Triangle angle 2$\beta +\gamma$ with a time dependent Dalitz analysis in $B^0$ decays using $D^- K^0 \pi^+$ final states following the method…
After a brief review of B_s^0 - \bar B_s^0 oscillations, we discuss the weak decays B_s^0 -> J/\psi\phi and B_s^0 -> J/\psi f_0(980) and the ratio R_{f_0/\phi} of their decay rates in the light of recent measurements by the LHCb, D0 and CDF…
A method for determining the $q^2$ dependent $\bar{K}^{*0}$ spin amplitudes of $\bar{B}^{0}\to \bar{K}^{*0}\mu^+\mu^-$ decays through a maximum likelihood fit to data is presented. While current experimental techniques extract a limited set…
A 4th generation could be consistent with the recently measured $\Delta m_{B_s}$ as well as ${\cal B}(b\to s\ell^+\ell^-)$, which are SM-like, but generate large $\sin2\Phi_{B_s} \simeq -0.5$ to -0.7. The sign is determined by the hint for…
Motivated by evidence for the existence of dark matter, many new physics models predict the pair production of new particles, followed by the decays into two invisible particles, leading to a momentum imbalance in the visible system. For…
An enhanced electroweak penguin amplitude due to the presence of unknown new physics can explain the discrepancies found between theory and experiment in the B -> pi K decays, in particular in A_CP(B^- -> pi^0 K^-) - A_CP(\bar{B}^0 -> pi^+…
We perform a time-dependent and time-integrated angular analysis of the decays $B^0\to\phi K^{*}(892)^0$, $\phi K^{*}_2(1430)^0$, and $\phi(K\pi)^{*0}_{0}$ with the final sample of about 465 million $\BB$ pairs recorded with the $\babar$…
A short summary is given of the current status of B physics. Reasons for physics beyond the Standard Model are discussed. Constraints on New Physics are given using measurements of B mixing, Bs mixing, and CP violation, along with |Vub.…
The latest BaBar measurements of the ratios ${\cal R}(D^{(*)})=\displaystyle{\frac{{\cal B}(B \to D^{(*)} \tau {\bar \nu}_\tau)}{{\cal B}(B \to D^{(*)} \mu {\bar \nu}_\mu)}}$ deviate from the Standard Model predictions at the global level…
We make a systematic analysis of the effects of new physics in the B decay amplitudes on the CP asymmetries in neutral B decays. Although these are expected to be smaller than new physics effects on the mixing amplitude, they are easier to…
The pure leptonic or semileptonic character of tau decays makes them a good laboratory to test the structure of the weak currents and the universality of their couplings to the gauge bosons. The hadronic $\tau$ decay modes constitute an…
A new phase for the measurements of radiative decay modes in $b \to s$ transitions has started with new measurements of exclusive modes by LHCb and with Belle-II showing distinctive promises in both inclusive and exclusive channels. After…
The recently obtained strong evidence for $D^0 - \bar D^0$ oscillations from the $B$ factories provides an important benchmark in our search for New Physics in charm transitions. While the theoretical verdict on the observed values of $x_D$…
We investigate the observables available in the angular distribution of B to K* mu+ mu- to identify those suitable for measurements in the first few years of LHC data taking. As experimental uncertainties will dominate, we focus on…
Recent measurements of $R_{D^*}$ have reduced tension with the Standard Model prediction. Taking all the present data into account, we obtain the values of the Wilson coefficients of each new physics four-fermion operator of a given Lorentz…
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…
Unconstrained partial-wave amplitudes obtained at discrete energies from fits to complete sets of experimental data may not vary smoothly with energy, and are in principle non-unique. We demonstrate how this behavior can be ascribed to the…