Related papers: Two Topics in $b$ Physics
We study the implications for $\Lambda_b \to \Lambda_c^*\ell\bar{\nu}_\ell$ and $\Lambda_b \to \Lambda_c^*\pi^-$ $[\Lambda_c^*=\Lambda_c(2595)$ and $\Lambda_c(2625)]$ decays that can be deduced from heavy quark spin symmetry (HQSS).…
We estimate the decay width difference $\Delta Gamma_d / \Gamma_d$ in the $B_d$ system including $1/m_b$ contributions and next-to-leading order QCD corrections, and find it to be around 0.3%. We explicitly show that the time measurements…
Several methods exist to measure $CP$ violation observables related to the CKM unitarity triangle angle $\gamma$ using $B$ meson decays. These observables are different for every $B$ meson decay considered, although the information they…
We demonstrate that polarization measurements in exclusive semileptonic B decays are powerful tools for unraveling non-standard model sources of T-violation. Measurements of the transverse polarization of the tau lepton in the B to D tau nu…
Decays of the kind $B_s\to D_s^{\pm}K^\mp, D_s^{\ast\pm}K^\mp, ...$ and $B_d\to D^{\pm}\pi^\mp, D^{\ast\pm}\pi^\mp, ...$ allow us to probe $\phi_s+\gamma$ and $\phi_d+\gamma$, respectively, involving the angle $\gamma$ of the unitarity…
Using a data sample of $(1.0087\pm 0.0044)\times 10^{10}$ $J/\psi$ events collected with the BESIII detector, the decays of $J/\psi\to\gamma\pi^{0} (\eta, \eta^\prime)\to\gamma\gamma\gamma$ are studied. Newly measured branching fractions…
We propose two different and complementary observables for singling out possible signals of physics beyond the standard model in the semi-leptonic decays $\Lambda_b \to \Lambda_c \ell{\bar \nu}_{\ell}$, both with the $\tau$ lepton and with…
We suggest to analyze the three-body decays B+- to $K+- p pbar$ and to $K+- \pi \pi$ by means of two different asymmetries. The former asymmetry, a T-odd one, vanishes and is proposed as a test for excluding biases in the experimental data.…
We carry out an analysis of the multibody decay cascade $\Lambda_b\to \Lambda^*_J J/\psi \to pK^- J/\psi$ with the $ \Lambda^*_J$ resonance including $\Lambda^*_{1520},\Lambda^*_{1600}$, and $\Lambda^*_{1800}$, and $J/\psi$ reconstructed by…
The recent anomalies in $b\to s\ell^+\ell^-$ transitions could originate from some New Physics beyond the Standard Model. Either to confirm or to rule out this assumption, more tests of $b\to s\ell^+\ell^-$ transition are needed. Polarized…
Various nonleptonic decay channels mediated by the quark-level subprocess $b\to s\bar{s} s$ show hints of deviation from the Standard Model expectations. We analyse the double-vector decay $B\to\phi K^\ast$ with different generic new…
We propose a new way for determining the CP violation angle $\gamma$ without any hadronic uncertainty. The suggested method is to use the two triangles formed by the decay amplitudes of $B^\pm\to (D^0,\bar D^0,D_{CP}^0)…
We apply the general formalism derived in N. Penalva et al. [Phys. Rev. D 101, 113004 (2020)] to the semileptonic decay of pseudoscalar mesons containing a $b$ quark. While present $B\to D^{(*)}$ data give the strongest evidence in favor of…
There are two main ways of looking for new physics, direct searches and precision measurements. The latter are sensitive to a broader spectrum of models; they also can be sensitive to higher energy scales than what can be reached through…
We construct a formalism which describes the resonances decaying into four pseudoscalar meson final states. This method is fully covariant and can be directly applied for the partial-wave analysis of high statistical data. Two topologies of…
We calculate the $\Lambda_b \to \Lambda_c \ell \nu$ form factors and decay rates for all possible $b\to c \ell\bar\nu$ four-Fermi interactions beyond the Standard Model, including nonzero charged lepton masses and terms up to order…
The $B_s^0 \rightarrow J/\psi \phi \phi$ decay is observed in $pp$ collision data corresponding to an integrated luminosity of 3 fb$^{-1}$ recorded by the LHCb detector at centre-of-mass energies of 7 TeV and 8 TeV. This is the first…
Using the QCD sum rules technique we study several aspects of the phenomenology of the b-flavoured strange meson $B_s^0$. In particular, we evaluate the mass of the particle, the leptonic constant and the form factors of the decays…
An analysis of the decay $\Lambda_b \to J/\psi(\to\mu^+\mu^-)\Lambda(\to p \pi^-)$ decay is performed to measure the $\Lambda_b$ polarization and three angular parameters in data from pp collisions at $\sqrt{s} =$ 7 and 8 TeV, collected by…
Inclusive $H_b \to X_s \, \gamma$ decays, with $H_b$ a beauty baryon, are treated exploiting an expansion up to the third order in the inverse of the $b$ quark mass $m_b$ and to LO in $\alpha_s$, keeping the dependence on the hadron spin.…