相关论文: Baryon-Meson Sum Rule for $b \to s \nu\bar\nu$
The $b \to c$ semileptonic sum rules provide relations between the decay rates of $B \to D^{(*)} \tau\bar\nu$ and $\Lambda_b \to \Lambda_c \tau\bar\nu$. Starting from the heavy quark and zero-recoil limits, we revisit the derivation of the…
We study heavy-hadron semileptonic decays proceeding via $b \to c$ transition, such as $B \to D^{(*)}\tau\bar{\nu}_\tau$ and $\Lambda_b \to \Lambda_c\tau\bar{\nu}_\tau$. In the heavy-quark limit, where the heavy-quark symmetry holds, we…
We investigate the $b\to c$ semileptonic sum rule in the presence of a massive sterile neutrino. Recent measurements of charged-current semitauonic $B$-meson decays exhibit a $\sim4\sigma$ deviation from the Standard Model predictions,…
The baryonic $b\to s$ transition $\Lambda_b\to\Lambda^{(*)}\nu{\bar\nu}$ is analyzed. We combine the mesonic counterpart $B^+\to K^+\nu{\bar\nu}$ and $B^0\to K^{*0}\nu{\bar\nu}$ as well as other observables involving $B$ mesons like…
Sum rules originally derived for the M\"ossbauer Effect are applied to weak semileptonic B decays. The sum rules follow from assuming that the decay by electroweak boson emission of an unstable nucleus or heavy quark in a bound system is…
Lepton flavor universality is a key prediction of the Standard Model of particle physics and any violation of it immediately indicates the existence of new physics. Given the recent more than $4\sigma$ discrepancy in charged current…
By combining potential models and QCD spectral sum rules (QSSR), we discuss the spectroscopy of the $(b\bar c)$ mesons and of the $(bcq)$, $(ccq)$ and $(bbq)$ baryons (${q}\equiv {d}$ or $s$), the decay constant and the (semi)leptonic decay…
In this work, we analyze the semileptonic decay processes of $\Lambda_b \to \Lambda_c$ in the light-cone sum rule approach. In order to calculate the form factors of the $\Lambda_b$ baryon transition matrix element, we use the light-cone…
We study the impact of including the baryonic decay $\Lambda_b\to \Lambda(\to p \pi^-)\mu^+\mu^-$ in a Bayesian analysis of $|\Delta B | = |\Delta S| = 1$ transitions. We perform fits of the Wilson coefficients $C_{9}$, $C_{9'}$, $C_{10}$…
We present an analysis of the rare exclusive $B$ decays $B\to K\nu\bar\nu$ and $B\to K^{*}\nu\bar\nu$ within the Standard Model (SM), in a model-independent manner, and in a number of new physics (NP) models. Combining new form factor…
Production of the matter-antimatter asymmetry in the $B$-Mesogenesis mechanism is directly related to the branching fraction of seemingly baryon number violating decays of $B$ mesons into a light Standard Model baryon and missing energy.…
The b to d d s bar transition gives extremely small branching ratios within the standard model, thus providing an appropriate ground for testing new physics. Using renormalization group technique we determine the Wilson coefficients and the…
Exclusive semileptonic B decays into $D_1$ and $D_2^*$ mesons are investigated including order $\Lambda_{QCD}/m_{c,b}$ corrections using the heavy quark effective theory. At zero recoil, the $\Lambda_{QCD}/m_{c,b}$ corrections can be…
$U$-spin symmetry, which reflects the symmetry between the down-type $d$ and $s$ quarks, is a powerful tool for analyzing heavy hadron weak decays. Motivated by recent experimental achievements in the bottom baryon sector, we study the…
We study the semileptonic decays of the $B_c$ meson into final charmonium states within the standard model and beyond. The relevant hadronic transition form factors are calculated in the framework of the covariant confined quark model…
We study semileptonic sum rules for $b \to c \tau \overline{\nu}$ transitions involving orbitally excited charm hadrons. Starting from the amplitude-level relation implied by the heavy quark symmetry, we construct sum rules relating these…
$B_s \to \mu^+ \mu^- \gamma$, measured at high $q^2$ as a partially reconstructed decay, can probe the origin of the existing discrepancies in semi-leptonic $b \to s$ and $b \to c$ decays. We perform a complete study of this possibility. We…
We investigate the semileptonic decays of B and D mesons into $\pi$ and $\rho$ mesons, respectively, by means of QCD sum rules. We find that for the vector formfactors involved the pole dominance hypothesis is valid to good accuracy with…
We obtain tree-level estimates of various differential branching ratios of heavy baryon decays with massive sterile neutrinos $\nu_{x}$ in the final state. Heavy sterile neutrinos can be searched for in heavy baryon decays with missing mass…
The transition form factors of $B_{(s)} \to S$, with $S$ denoting a scalar meson, are investigated in the light-cone sum rules approach. The numerical values are approximately twice as large as that estimated in the light-front quark model…