相关论文: The Decay Sigma^+ -> p l^+ l^- within the Standard…
We consider the exclusive B_s -> phi mu+ mu- process in the standard model using a constituent quark loop model approach together with a simple parameterization of the quark dynamics. The model allows to compute the decay form factors and…
Recent disagreement between experimental measurments of CP violating asymmetry in D -> K+ K- and D ->pi+ pi- and theoretical Standard model expectation motivated many studies within the Standard model and beyond. Rare charm decays offer new…
A search for the decay KS -> mu+ mu- is performed, based on a data sample of 1.0 fb^-1 of pp collisions at \sqrt{s}=7 TeV collected by the LHCb experiment at the Large Hadron Collider. The observed number of candidates is consistent with…
More than $3\sigma$ deviations from the standard model are observed in the angular observable $P'_5$ of $B\to K^* \mu^+ \mu^-$ and muon $g-2$. To resolve these anomalies, we extend the standard model by adding two leptoquarks. It is found…
The first observation of the decay K^+ --> pi^+ gamma gamma is reported. A total of 31 events was observed with an estimated background of 5.1 +- 3.3 events in the pi+ momentum range from 100 MeV/c to 180 MeV/c. The corresponding partial…
This presentation reports on the first experimental search for the decay Klong to $\pi^0 \pi^0 \mu^+ \mu^-$ based on data collected by the KTeV experiment. Although this decay mode is possible within the standard model, its rate is phase…
Motivated by the recent evidence for direct CP-violation in D0 -> h+h- decays, we provide an exhaustive study of both Cabibbo-favored and Cabibbo-suppressed (singly and doubly) D0 -> h1+h2-l+l- decays. In particular, we study the Dalitz…
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…
Several deviations from the Standard Model predictions have been recently observed in the decays mediated by $b \rightarrow s l^+ l^-$ transitions. These could be pointing towards new vector-current contributions or could be explained by…
In this article, we examine the Standard Model extended by a $Y=0$ real Higgs triplet, the $\Delta$SM. It contains a $CP$-even neutral Higgs ($\Delta^0$) and two charged Higgs bosons ($\Delta^\pm$), which are quasi-degenerate in mass. We…
The HyperCP collaboration has observed three events for the decay $\Sigma^+ \to p \mu^+ \mu^-$. The three events may be interpreted as a new narrow-width CP-odd scalar $a$ with the mass $214.3 \pm 0.5$ MeV. Here $a$ decays dominantly into…
One-loop contributions to the decay $H\rightarrow \nu_l\bar{\nu}_l\gamma$ with $l=e, \mu, \tau$ within standard model framework are revisited in this paper. We derive two representations for the form factors in this calculation. As a…
I present new results for the Standard-Model predictions of the differential decay rates for $H\to \ell^{+} \ell^{-} \gamma$, where $\ell=e, \mu$, and the forward-backward asymmetries defined in terms of the flight direction of the photon…
The decay K- -> pi0 e- nu is studied using in-flight decays detected with the ISTRA+ spectrometer. About 920K events are collected for the analysis. The lambda+ slope parameter of the decay form-factor f+(t) in the linear approximation…
This review summarizes the current experimental results on rare B0_(s) -> mu+mu- decays of the Tevatron experiments CDF and D0, and the LHC experiments ATLAS, CMS and LHCb. The experimental branching fraction upper limits for the B0_s ->…
The long-awaited $B_s\to \mu^+\mu^-$ mode has finally been observed at rate consistent with Standard Model, albeit lower by 1.2$\sigma$. There is some hint for New Physics in the rarer $B_d^0 \to \mu^+\mu^-$ decay, especially if the…
We study long-distance effects in rare exclusive semileptonic decays B -> (K, K*) (l+ l-, nu bar{nu}) and analyze dilepton spectra and asymmetries within the framework of the Standard Model. The form factors, describing the meson transition…
We investigate the rare baryonic exclusive decays of $\Lambda_b\to \Lambda l^+ l^- (l=e,\mu,\tau)$ with polarized $\Lambda $. Under the approximation of the heavy quark effective theory (HQET), in the standard model we derive the…
We explain the 2.3 sigma deviation in the recent measurements of the neutral B mesons decay into muon pairs from the standard model prediction in the framework of supersymmetric grand unified models using anti-symmetric coupling as a new…
The rare baryonic decay $\Lambda_b\to \Lambda(\to p\pi^-)\mu^+\mu^-$ provides valuable complementary information compared to the corresponding mesonic $b\to s\mu^+\mu^-$ transition. In this paper, using the latest high-precision lattice QCD…