相关论文: Isospin violation in e+ e- --> B Bbar

We report on measurements of the decays of $\overline{B}$ mesons into the semileptonic final states $\overline{B} \to D^{(*)} \pi^+\pi^- \ell^-\overline{\nu}$, where $D^{(*)}$ represents a $D$ or $D^*$ meson and $\ell^-$ is an electron or a…

We present a search for the decay of a B0 or B0bar meson to a K*0bar K0 or K*0 K0bar final state, using a sample of approximately 232 million BBbar events collected with the BABAR detector at the PEP-II asymmetric energy e+e- collider at…

Using the initial-state radiation method, the $e^+e^- \to K_S K_L$ cross section from 1.98 to 2.54 GeV is measured in a data sample of 469 fb$^{-1}$ collected with the BABAR detector. The results are used in conjunction with previous BABAR…

Influence of the isospin-violating (\rho^0, \omega)-mixing is discussed for any pair of decays of \rho^0, \omega into the same final state. It is demonstrated, in analogy to the CP-violation in neutral kaon decays, that isospin violation…

We present a measurement of the time-dependent charge-parity (CP) violation parameters in B0 -> pi+ pi- decays. The results are obtained from the final data sample containing 772 million BBbar pairs collected at the Upsilon(4S) resonance…

The calculation of the R-ratio of electron-positron annihilation into hadrons is discussed. The method, which enables one to properly account for all the effects due to continuation of the spacelike perturbative results into the timelike…

In the framework of the nonrelativistic diquark model of the heavy baryons and the perturbative approach of QCD we predict the value and energy dependence for the total cross section of the Lambda_b- and Sigma_b^* -baryons pair production…

Using recent BABAR, CMD-3 and SND data, the sum of $e^+e^- \to 3(\pi^+\pi^-), 2(\pi^+\pi^-\pi^0), p\bar{p}, n\bar{n}$ cross sections is obtained. Unlike $e^+e^- \to 3(\pi^+\pi^-)$ and $e^+e^- \to 2(\pi^+\pi^-\pi^0)$ processes, no structures…

We compute the isospin asymmetries in $B \to (K^*,\rho) \gamma$ and $B\to (K,K^*,\rho) l^+l^-$ for low lepton pair invariant mass $q^2$, within the Standard Model (SM) and beyond the SM (BSM) in a generic dimension six operator basis.…

Measurements of Rb, the ratio of the bbbar cross-section to the qqbar cross- section in e+e- collisions, are presented. The data were collected by the OPAL experiment at LEP at centre-of-mass energies between 182 GeV and 209 GeV. Lepton,…

We present measurements of branching fractions and CP-violating asymmetries in B0 -> rho+- pi-+ and B0 -> rho- K+ decays. The results are obtained from a data sample of 88.9 10^6 Upsilon(4S) -> B Bbar decays collected with the BABAR…

We show that in collisions with neutron rich heavy ions at energies around the production threshold K^0 and K^+ yields might probe the isospin dependent part of the nuclearEquation of State (EoS) at high baryon densities. In particular we…

We discusses the charge asymmetry in $ B\rightarrow D\bar DK$ decays with an invariant mass of the $D\bar D$ pair near the $\Psi(3770)$ resonance. Unlike $ \Psi (3770) $ decays in $ e^+e^- $ annihilation, in $B^+$ decays the probability of…

We describe searches for decays of B mesons to the charmless final states eta' eta' K. The data consist of 228 million B Bbar pairs produced in e+ e- annihilation, collected with the BaBar detector at the Stanford Linear Accelerator Center.…

The beam spin asymmetry (BSA) in the exclusive reaction ep->ep pi0 was measured with the CEBAF 5.77 GeV polarized electron beam and Large Acceptance Spectrometer(CLAS). The xB, Q2, t and phi dependences of the pi0 BSA are presented in the…

The recently completed calculation of the full electroweak O(alpha) corrections to the charged-current four-fermion production processes e+e- --> nu_tau tau+ mu- anti-nu_mu, u anti-d mu- anti-nu_mu, and u anti-d s anti-c is briefly…

Starting from the low-energy structure derived from QCD, we extend the amplitudes for four-pion production in e+ e- annihilation and tau decays up to invariant four-pion masses of 1 GeV. Cross sections and branching ratios BR(rho^0 -> 4 pi)…

Using a sample of 232 x 10^6 Upsilon(4S)--> B B-bar events collected with the BABAR detector at the PEP-II B-factory we study the decay B- --> [K+ pi-]_D K*- where the K+ pi- is either from a Cabibbo-favored D0-bar decay or…

The heavy ion total cross section for continuum e+ e- pair production has been calculated to all orders in Z alpha. The formula resulting from an exact solution of the semiclassical Dirac equation in the ultrarelativistic limit is evaluated…

We present an analysis of inclusive Omega_c^0 baryon production and decays in 230.5 fb^-1 of data recorded with the BABAR detector at the PEP-II asymmetric-energy e+ e- collider at the Stanford Linear Accelerator Center. Omega_c^0 baryons…