4,221 research outputs found
The CLEO-III Ring Imaging Cherenkov Detector
The CLEO-III Detector upgrade for charged particle identification is
discussed. The RICH design uses solid LiF crystal radiators coupled with
multi-wire chamber photon detectors, using TEA as the photosensor, and
low-noise Viking readout electronics. Results from our beam test at Fermilab
are presented.Comment: Invited talk by R.J. Mountain at ``The 3rd International Workshop on
Ring Imaging Cherenkov Detectors," a research workshop of the Israel Science
Foundation, Ein-Gedi, Dead-Sea, Israel, Nov. 15-20, 1998, 14 pages, 9 figure
Performance of the CLEO III LiF-TEA Ring Imaging Cherenkov Detector in a High Energy Muon Beam
The CLEO III Ring Imaging Cherenkov detector uses LiF radiators to generate Cherenkov photons which are then detected by proportional wire chambers using a mixture of CH and TEA gases. The first two photon detector modules which were constructed, were taken to Fermilab and tested in a beam dump that provided high momentum muons. We report on results using both plane and "sawtooth" shaped radiators. Specifically, we discuss the number of photoelectrons observed per ring and the angular resolution. The particle separation ability is shown to be sufficient for the physics of CLEO III
Moments of the B Meson Inclusive Semileptonic Decay Rate using Neutrino Reconstruction
We present a measurement of the composition of B meson inclusive semileptonic
decays using 9.4 fb^-1 of e^+e^- data taken with the CLEO detector at the
Upsilon(4S) resonance. In addition to measuring the charged lepton kinematics,
the neutrino four-vector is inferred using the hermiticity of the detector. We
perform a maximum likelihood fit over the full three-dimensional differential
decay distribution for the fractional contributions from the B -> X_c l nu
processes with X_c = D, D*, D**, and nonresonant X_c, and the process B -> X_u
l nu. From the fit results we extract the first and second moments of the M_X^2
and q^2 distributions with minimum lepton-energy requirements of 1.0 GeV and
1.5 GeV. We find = 0.456 +- 0.014 +- 0.045 +- 0.109
(GeV/c^2)^2 with a minimum lepton energy of 1.0 GeV and =
0.293 +- 0.012 +- 0.033 +- 0.048 (GeV/c^2)^2 with minimum lepton energy of 1.5
GeV. The uncertainties are from statistics, detector systematic effects, and
model dependence, respectively. As a test of the HQET and OPE calculations, the
results for the M^X_c moment as a function of the minimum lepton energy
requirement are compared to the predictions.Comment: 26 pages postscript, als available through
http://w4.lns.cornell.edu/public/CLNS/, Submitted to PRD (back-to-back with
following preprint hep-ex/0403053
Search for a Scalar Bottom Quark with Mass 3.5-4.5 GeV/
We report on a search for a supersymmetric meson with mass
between 3.5 and 4.5 GeV/ using 4.52 of integrated
luminosity produced at GeV, just below the threshold, and collected with the CLEO detector. We find no evidence
for a light scalar bottom quark.Comment: 10 pages postscript, also available through
http://w4.lns.cornell.edu/public/CLN
First Observation of barB0 to D*0 pi+pi+pi-pi- Decays
We report on the observation of B0bar -> D*0 pi+ pi+ pi- pi- decays. The
branching ratio is (0.30 +/- 0.07 +/- 0.06)%. Interest in this particular mode
was sparked by Ligeti, Luke and Wise who propose it as a way to check the
validity of factorization tests in B0bar -> D*+ pi+ pi- pi- pi0 decays.Comment: 11 pages postscript, also available through
http://w4.lns.cornell.edu/public/CLNS, Version to appear in Phys. Rev.
Observation of the Hadronic Transitions Chi_{b 1,2}(2P) -> omega Upsilon(1S)
The CLEO Collaboration has observed the first hadronic transition among
bottomonium (b bbar) states other than the dipion transitions among vector
states, Upsilon(nS) -> pi pi Upsilon(mS). In our study of Upsilon(3S) decays,
we find a significant signal for Upsilon(3S) -> gamma omega Upsilon(1S) that is
consistent with radiative decays Upsilon(3S) -> gamma chi_{b 1,2}(2P), followed
by chi_{b 1,2} -> omega Upsilon(1S). The branching ratios we obtain are
Br(chi_{b1} -> omega Upsilon(1S) = 1.63 (+0.35 -0.31) (+0.16 -0.15) % and
Br(chi_{b2} -> omega Upsilon(1S) = 1.10 (+0.32 -0.28) (+0.11 - 0.10)%, in which
the first error is statistical and the second is systematic.Comment: submitted to XXI Intern'l Symp on Lepton and Photon Interact'ns at
High Energies, August 2003, Fermila
Hadronic Structure in the Decay
We report on a study of the invariant mass spectrum of the hadronic system in
the decay tau- -> pi- pi0 nu_tau. This study was performed with data obtained
with the CLEO II detector operating at the CESR e+ e- collider. We present fits
to phenomenological models in which resonance parameters associated with the
rho(770) and rho(1450) mesons are determined. The pi- pi0 spectral function
inferred from the invariant mass spectrum is compared with data on e+ e- -> pi+
pi- as a test of the Conserved Vector Current theorem. We also discuss the
implications of our data with regard to estimates of the hadronic contribution
to the muon anomalous magnetic moment.Comment: 39 pages postscript, also available through
http://w4.lns.cornell.edu/public/CLN
Study of Charmless Hadronic B Meson Decays to Pseudoscalar-Vector Final States
We report results of searches for charmless hadronic B meson decays to
pseudoscalar(pi^+-,K^+-,Pi^0 or Ks^0)-vector(Rho, K* or Omega) final states.
Using 9.7 million BBbar pairs collected with the CLEO detector, we report first
observation of B^- --> Pi^-Rho^0, B^0 --> Pi^+-Rho^-+ and B^- --> Pi^-Omega,
which are expected to be dominated by hadronic b --> u transitions. The
measured branching fractions are (10.4+3.3-3.4+-2.1)x10^-6,
(27.6+8.4-7.4+-4.2)x10^-6 and (11.3+3.3-2.9+-1.4)x10^-6, respectively.
Branching fraction upper limits are set for all the other decay modes
investigated.Comment: 10 pages postscript, also available through
http://w4.lns.cornell.edu/public/CLN
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