28 research outputs found
Study of Radiation Damage in Lead Tungstate Crystals Using Intense High Energy Beams
We report on the effects of radiation on the light output of lead tungstate crystals. The crystals were irradiated by pure, intense high energy electron and hadron beams as well as by a mixture of hadrons, neutrons and gammas. The crystals were manufactured in Bogoroditsk, Apatity (both Russia), and Shanghai (China). These studies were carried out at the 70-GeV proton accelerator in Protvino
Precision Measurement of Energy and Position Resolutions of the BTeV Electromagnetic Calorimeter Prototype
The energy dependence of the energy and position resolutions of the electromagnetic calorimeter prototype made of lead tungstate crystals produced in Bogoroditsk (Russia) and Shanghai (China) is presented. These measurementswere carried out at the Protvino accelerator using a 1 to 45 GeV electron beam. The crystals were coupled to photomultiplier tubes. The dependence of energy and position resolutions on different factors as well as the measured electromagnetic shower lateral profile are presented
Study of Radiation Damage in Lead Tungstate Crystals Using Intense High Energy Beams
We report on the effects of radiation on the light output of lead tungstate
crystals. The crystals were irradiated by pure, intense high energy electron
and hadron beams as well as by a mixture of hadrons, neutrons and gammas. The
crystals were manufactured in Bogoroditsk, Apatity (both Russia), and Shanghai
(China). These studies were carried out at the 70-GeV proton accelerator in
Protvino
Search for Lepton-Flavor-Violating Decays of B Mesons
We have searched a sample of 9.6 million BB-bar events for the
lepton-flavor-violating decays B --> h e^{+-} mu^{-+}, B^+ --> h^- e^+ e^+, B^+
--> h^- e^+ mu^+, and B^+ --> h^- mu^+ mu^+, where h is pi, K, rho, and
K*(892), a total of sixteen modes. We find no evidence for these decays, and
place 90% confidence level upper limits on their branching fractions that range
from 1.0 to 8.3 X 10^{-6}.Comment: 8 pages postscript, also available through
http://w4.lns.cornell.edu/public/CLNS, PRD R
Measurement of Inclusive B --> psi Production
Using the combined CLEO II and CLEO II.V data sets of 9.1 fb^{-1} at the
Upsilon(4S), we measure properties of Psi mesons produced directly from decays
of the B meson, where ``B'' denotes an admixture of B+, B-, B0, and B0bar, and
``Psi'' denotes either J/Psi or Psi(2S). We report first measurements of Psi
polarization in B -> Psi(direct) X: alpha(J/Psi) = -0.30 {+0.07 -0.06 stat}
{+-0.04 syst} and alpha(Psi(2S)) = -0.45 {+0.22 -0.19 stat} {+-0.04 syst}. We
also report improved measurements of the momentum distributions of Psi produced
directly from B decays, correcting for measurement smearing. Finally, we report
measurements of the inclusive branching fraction for B -> Psi X and B -> Chi_c1
X.Comment: 8 pages postscript, also available through
http://w4.lns.cornell.edu/public/CLNS, submitted to PR
Measurement of Exclusive B Decays to Final States Containing a Charmed Baryon
Using data collected by the CLEO detector in the Upsilon(4S) region, we
report new measurements of the exclusive decays of B mesons into final states
of the type Lambda_c^+ p-bar n(pi), where n=0,1,2,3. We find signals in modes
with one, two and three pions and an upper limit for the two body decay
Lambda_c^+ pbar. We also make the first measurements of exclusive decays of B
mesons to Sigma_c p-bar n(pi), where n=0,1,2. We find signals in modes with one
and two pions and an upper limit for the two body decay Sigma_c p-bar.
Measurements of these modes shed light on the mechanisms involved in B decays
to baryons.Comment: 11 pages postscript, also available through
http://w4.lns.cornell.edu/public/CLNS, submitted to PR
Observation of B to K_S^0 pi+ pi- and Evidence for B to K*pm pi mp
We report on a search for charmless hadronic B decays to the three-body final
states, K0S h+ pi-, K+ h- pi0, K0S h+ pi0 (h+- denotes a charged pion or kaon),
and their charge conjugates, using 13.5 fb^{-1} of integrated luminosity
produced with center-of-mass energies near 10.6 GeV, and collected with the
CLEO detector. We observe the decay B --> K0 pi+ pi- with a branching fraction
(50 +10-9(stat.) +-7(syst.)) x 10^{-6} and the decay B --> K*+(892) pi- with a
branching fraction (16 +6-5(stat.) +-2(syst.)) x 10^{-6}.Comment: 11 pages postscript, also available through
http://w4.lns.cornell.edu/public/CLNS, submitted to PR
Search for Neutrinoless tau Decays Involving the K_S^0 Meson
We have searched for lepton flavor violating decays of the tau lepton with
one or two KS0 mesons in the final state. The data used in the search were
collected with the CLEO II and II.V detectors at the Cornell Electron Storage
Ring (CESR) and correspond to an integrated luminosity of 13.9 fb^-1 at the
Upsilon(4S) resonance. No evidence for signals were found, therefore we have
set 90% confidence level (C.L.) upper limits on the branching fractions B(tau
-> e KS0) mu KS0) e 2KS0) < 2.2e-6, and
B(tau -> mu 2KS0) < 3.4e-6. These represent significantly improved upper limits
on the two-body decays and first upper limits on the three-body decays.Comment: 9 pages postscript, also available through
http://w4.lns.cornell.edu/public/CLNS, submitted to PRD Rapid Communication