Search results for "Branching"

Search for the decayB+→Ks0Ks0π+

2009

We search for charmless decays of charged B mesons to the three-body final state (KSKS0)-K-0 pi(+). Using a data sample of 423.7 fb(-1) collected at the Gamma(4S) resonance with the BABAR detector, corresponding to (465.1 +/- 5.1) x 10(6) (B) over bar B pairs, we find no significant signal and determine a 90% confidence level upper limit on the branching fraction of 5.1 x 10(-7).

Evidence ofB+→τ+νdecays with hadronicBtags

2013

We present a search for the decay B+→τ+ν using 467.8×10^6 BB pairs collected at the Υ(4S) resonance with the BABAR detector at the SLAC PEP-II B-Factory. We select a sample of events with one completely reconstructed B- in the hadronic decay mode (B-→D(*)0X- and B-→J/ψX-). We examine the rest of the event to search for a B+→τ+ν decay. We identify the τ+ lepton in the following modes: τ+→e+νν , τ+→μ+νν , τ+→π+ν and τ+→ρ+ν . We find an excess of events with respect to the expected background, which excludes the null signal hypothesis at the level of 3.8σ (including systematic uncertainties) and corresponds to a branching fraction value of B(B+→τ+ν)=(1.83_(-0.49)^(+0.53)(stat)±0.24(syst))×10^(…

Measurement of the form factors in the decayD+→ωe+νeand search for the decayD+→ϕe+νe

2015

Using 2.92 fb(-1) of electron-positron annihilation data collected at a center-of-mass energy of root s = 3.773 GeV with the BESIII detector, we present an improved measurement of the branching fra ...

B-physics results from LEP

1996

Abstract The LEP collider continues to improve our knowledge and understanding of B-physics. Recent results are presented in the areas of B-hadron lifetimes, BB oscillations, B-spectroscopy and rare B-decays.

Measurement of the Inclusive Charmless Semileptonic Branching Ratio ofBMesons and Determination of|Vub|

2004

We report a measurement of the inclusive charmless semileptonic branching fraction of B mesons in a sample of 89 x 10(6) (-)BB events recorded with the BABAR detector at the Upsilon(4S) resonance. Events are selected by fully reconstructing the decay of one B meson and identifying a charged lepton from the decay of the other B meson. The number of signal events is extracted from the mass distribution of the hadronic system accompanying the lepton and is used to determine the ratio of branching fractions B((-)B-->X(u)lnu;)/B((-)B-->Xlnu;)=[2.06+/-0.25(stat)+/-0.23(syst)+/-0.36(theo)]x10(-2). Using the measured branching fraction for inclusive semileptonic B decays, we find B((-)B-->X(u)lnu;)…

Coulomb excitation of exotic nuclei at the R3B-LAND setup

2012

Exotic Ni isotopes have been measured at the R3B-LAND setup at GSI in Darmstadt, using Coulomb excitation in inverse kinematics at beam energies around 500 MeV/u. As the experimental setup allows kinematically complete measurements, the excitation energy was reconstructed using the invariant mass method. The GDR and additional low-lying strength have been observed in 68Ni, the latter exhausting 4.1(1.9)% of the E1 energy-weighted sum rule. Also, the branching ratio for the non-statistical decay of the excited 68Ni nuclei was measured and amounts to 24(4)%.

β -decay half-lives and β -delayed neutron emission probabilities for several isotopes of Au, Hg, Tl, Pb, and Bi, beyond N=126

2017

Background: Previous measurements of Beta-delayed neutron emitters comprise around 230 nuclei, spanning from the 8He up to 150La. Apart from 210Tl, with a minuscule branching ratio of 0.07%, no other neutron emitter is measured yet beyond A = 150. Therefore new data are needed, particularly in the heavy mass region around N=126, in order to guide theoretical models and to understand the formation of the third r-process peak at A 195. Purpose: To measure both, Beta-decay half-lives and neutron branching ratios of several neutron-rich Au, Hg, Tl, Pb and Bi isotopes beyond N = 126. Method: Ions of interest are produced by fragmentation of a 238U beam, selected and identifed via the GSI-FRS fra…

β decay of the very neutron-deficient Ge60 and Ge62 nuclei

2021

We report here the results of a study of the $\beta$ decay of the proton-rich Ge isotopes, $^{60}$Ge and $^{62}$Ge, produced in an experiment at the RIKEN Nishina Center. We have improved our knowledge of the half-lives of $^{62}$Ge (73.5(1) ms), $^{60}$Ge (25.0(3) ms) and its daughter nucleus, $^{60}$Ga (69.4(2) ms). We measured individual $\beta$-delayed proton and $\gamma$ emissions and their related branching ratios. Decay schemes and absolute Fermi and Gamow-Teller transition strengths have been determined. The mass excesses of the nuclei under study have been deduced. A total $\beta$-delayed proton-emission branching ratio of 67(3)% has been obtained for $^{60}$Ge. New information has…

2018

We have performed the most comprehensive resonance-model fit of π-π-π+ states using the results of our previously published partial-wave analysis (PWA) of a large data set of diffractive-dissociation events from the reaction π-+p→π-π-π++precoil with a 190  GeV/c pion beam. The PWA results, which were obtained in 100 bins of three-pion mass, 0.5<m3π<2.5  GeV/c2, and simultaneously in 11 bins of the reduced four-momentum transfer squared, 0.1<t′<1.0  (GeV/c)2, are subjected to a resonance-model fit using Breit-Wigner amplitudes to simultaneously describe a subset of 14 selected waves using 11 isovector light-meson states with JPC=0-+, 1++, 2++, 2-+, 4++, and spin-exotic 1-+ quantum numbers. T…

LeptonicCPasymmetries in flavor-changingH0decays

1993

Leptonic flavor-changing ${H}^{0}$ decays with branching ratios of the order of ${10}^{\ensuremath{-}5}$-${10}^{\ensuremath{-}6}$ may constitute an interesting framework when looking for large $\mathrm{CP}$-violating effects. We show that leptonic $\mathrm{CP}$ asymmetries of an intermediate ${H}^{0}$ boson can be fairly large in natural scenarios of the minimal standard model with right-handed neutrinos, at a level that may be probed at future ${H}^{0}$ factories.