Vaclav Zácek

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The branching fractions of the exclusive decays B0-->K(*0)gamma and B+-->K(*+)gamma are measured from a sample of (22.74+/-0.36)x10(6) BB decays collected with the BABAR detector at the PEP-II asymmetric e(+)e(-) collider. We find B (B0-->K(*0)gamma) = [4.23+/-0.40(stat)+/-0.22(syst)]x10(-5), B(B+-->K(*+)gamma) = [3.83+/-0.62(stat)+/-0.22(syst)]x10(-5) and(More)
New data are reported from the operation of a 2 liter C3F8 bubble chamber in the SNOLAB underground laboratory, with a total exposure of 211.5 kg days at four different energy thresholds below 10 keV. These data show that C3F8 provides excellent electron-recoil and alpha rejection capabilities at very low thresholds. The chamber exhibits an electron-recoil(More)
C. Amole, M. Ardid, D. M. Asner, D. Baxter, E. Behnke, P. Bhattacharjee, H. Borsodi, M. Bou-Cabo, S. J. Brice, D. Broemmelsiek, K. Clark, J. I. Collar, P. S. Cooper, M. Crisler, C. E. Dahl, S. Daley, M. Das, F. Debris, N. Dhungana, S. Fallows, J. Farine, I. Felis, R. Filgas, F. Girard, G. Giroux, A. Grandison, M. Hai, J. Hall, O. Harris, M. Jin, C. B.(More)
We present measurements of time-dependent CP-violating asymmetries in neutral B decays to several CP eigenstates. The measurement uses a data sample of 23x10(6) Upsilon(4S)-->BbarB decays collected by the BABAR detector at the PEP-II asymmetric B Factory at SLAC. In this sample, we find events in which one neutral B meson is fully reconstructed in a CP(More)
We present an updated measurement of time-dependent CP-violating asymmetries in neutral B decays with the BABAR detector at the PEP-II asymmetric B Factory at SLAC. This result uses an additional sample of Upsilon(4S) decays collected in 2001, bringing the data available to 32 x 10(6) BB macro pairs. We select events in which one neutral B meson is fully(More)
C. Amole, M. Ardid, I. J. Arnquist, D. M. Asner, D. Baxter, E. Behnke, P. Bhattacharjee, H. Borsodi, M. Bou-Cabo, S. J. Brice, D. Broemmelsiek, K. Clark, J. I. Collar, P. S. Cooper, M. Crisler, C. E. Dahl, M. Das, F. Debris, S. Fallows, J. Farine, I. Felis, R. Filgas, M. Fines-Neuschild, F. Girard, G. Giroux, J. Hall, O. Harris, E.W. Hoppe, C. M. Jackson,(More)
Searches for unstable neutral and charged heavy leptons, N and L±, and for excited states of neutral and charged leptons, ν∗, e∗, μ∗, and τ∗, have been performed in e+e− collisions using data collected by the OPAL detector at LEP. The data analysed correspond to an integrated luminosity of about 58 pb−1 at a centre-of-mass energy of 183 GeV, and about 10(More)
Photonic events with large missing energy have been observed in ee collisions at centreof-mass energies of 130, 136 and 183 GeV collected in 1997 using the OPAL detector at LEP. Results are presented for event topologies with a single photon and missing transverse energy or with an acoplanar photon pair. Cross-section measurements are performed within the(More)
The PICASSO collaboration observed for the first time a significant difference between the acoustic signals induced by neutrons and alpha particles in a detector based on superheated liquids. This new discovery offers the possibility of improved background suppression and could be especially useful for dark matter experiments. This new effect may be(More)
The production of J/psi mesons in continuum e(+)e(-) annihilations has been studied with the BABAR detector at energies near the Upsilon(4S) resonance. The mesons are distinguished from J/psi production in B decays through their center-of-mass momentum and energy. We measure the cross section e(+)e(-)-->J/psi X to be 2.52+/-0.21+/-0.21 pb. We set a 90% C.L.(More)