Related papers: $B^{(*)}\bar B^{(*)}$ intermediate state contribut…
In this work, we investigate the characteristics of the spin-singlet state $\eta_b$ of the bottomonia family via the radiative decays of $\Upsilon(nS)\to \eta_b+\gamma$. The theoretical estimation of the decay widths is carried out in terms…
The $\eta$ transitions of $\Upsilon(4S,5S)$ into $\Upsilon(1S,2S)$ are studied in the rescattering model by considering the final state interactions above the $B\bar B$ threshold. The width of the $\eta$ transition of $\Upsilon(4S)$ into…
We have performed a search for the eta_b(1S) meson in the radiative decay of the Upsilon(2S) resonance using a sample of 91.6 million Upsilon(2S) events recorded with the BABAR detector at the PEP-II B factory at the SLAC National…
We calculate the decay rate ratios for OZI allowed decays of Upsilon(5S) to two B mesons by using the decay amplitudes which incorporate the wave function of the Upsilon(5S) state. We obtain the results that the branching ratio of the…
We study the $\Upsilon(1S)$ radiative decays to $\gamma \pi^+ \pi^-$ and $\gamma K^+ K^-$ using data recorded with the BaBar detector operating at the SLAC PEP-II asymmetric-energy $e^+ e^-$ collider at center-of-mass energies at the…
We report the first observation of the radiative decay of the $\Upsilon(1S)$ into a charmonium state. The statistical significance of the observed signal of $\Upsilon(1S) \to \gamma \chi_{c1}$ is 6.3 standard deviations including…
We present a limit on the branching fraction for the decay $B^0 \to \gamma \gamma$ using data collected at the $\Upsilon(4S)$ resonance with the BABAR detector at the PEP-II asymmetric--energy $e^+e^-$ collider. Based on the observation of…
We study the $\Upsilon(1S)$ radiative decays to $\gamma \pi^+ \pi^-$ and $\gamma K^+ K^-$ using data recorded with the BaBar detector operating at the SLAC PEP-II asymmetric-energy $e^+e^-$ collider at center-of-mass energies at the…
The decays of $\Upsilon(1s)\to\gamma(\eta',\eta)$ are studied by an approach which has successfully predicted the ratio $\frac{\Gamma(J/\psi\to\gamma\eta')}{\Gamma(J/\psi\to\gamma\eta)}$. Strong dependence on quark mass has been found in…
About 90% of Bs-bar Bs pairs produced at the Upsilon(5s) resonance are initially Bs*-bar Bs* pairs which decay radiatively to Bs-bar Bs. This implies that the Bs pair will then be in an eigenstate of charge conjugation (i.e. C=-1) and…
In order to explain the observed unusually large dipion transition rates of $\Upsilon(10870)$, the scalar resonance contributions in the re-scattering model to the dipion transitions of $\Upsilon(4S)$ and $\Upsilon(5S)$ are studied. Since…
We report the observation of $\Upsilon(2S)\to\gamma\eta_{b}(1S)$ decay based on analysis of the inclusive photon spectrum of $24.7$ fb$^{-1}$ of $e^+ e^-$ collisions at the $\Upsilon(2S)$ center-of-mass energy collected with the Belle…
We report evidence for the ground state of bottomonium, eta_b(1S), in the radiative decay Upsilon(3S) --> gamma eta_b in e^+e^- annihilation data taken with the CLEO III detector. Using 6 million Upsilon(3S) decays, and assuming…
We introduce a new method for the determination of the ratio of production fractions $R^{\pm0}=\mathcal B(\Upsilon(4S)\to B^+B^-)/\mathcal B(\Upsilon(4S)\to B^0\bar B^0)$ based on $\bar B\to D^{(*)}\ell\bar \nu$ decays. Given the importance…
Recent data from Belle show unusually large partial widths Upsilon(5S) --> Upsilon(1S) pi^+pi^- and \Upsilon(5S) --> \Upsilon(2S) pi^+ pi^-. The Z(4430) narrow resonance also reported by Belle in psi' pi^+ spectrum has the properties…
We give an estimate of the $C$-even $B^0 \bar{B^0}$ background coming from the radiative decay $\Upsilon(4S)\to B^0\bar B^0\gamma$ at $B$-factories. Our result $B(\Upsilon(4S)\to B^0\bar B^0\gamma) \simeq 3 \times 10^{-9}$ shows that such…
We report a measurement of the branching fraction e^+e^- --> B0B0bar with a data sample of 81.7 fb^-1 collected at the Upsilon(4S) resonance with the BABAR detector at the PEP-II asymmetric-energy e^+e^- storage ring. Using partial…
$\Upsilon(1s)\to\gamma(\eta',\eta, f_2(1270))$ are studied by an approach in which the glueball components of these mesons play dominant role. Strong dependence on quark mass has been found in the decays $(J/\psi,…
We have evaluated the decay modes of the $\Upsilon(4s), \Upsilon(3d), \Upsilon(5s), \Upsilon(6s)$ states into $B\bar B, B\bar B^*+c.c., B^* \bar B^*, B_s \bar B_s, B_s \bar B^*_s +c.c., B^*_s \bar B_s^* $ using the $^3P_0$ model to…
We report the first observation of the radiative transition h_b(1P)->eta_b(1S)gamma, where the h_b(1P) is produced in Upsilon(5S)->h_b(1P)pi+pi- dipion transitions. We measure the eta_b(1S) mass to be (9401.0+-1.9+1.4-2.4)MeV/c^2 with a…