1,060 research outputs found
Measurement of CP Violation at the without Time Ordering or
I derive the expressions for the CP-violating asymmetry arising from
interference between mixed and direct decays in the Upsilon(4S) system, for the
case in which only one of the B decay times is observed, integrating over the
decay time of the other B. I observe that neither the difference of the decay
times Delta t, nor even their time-ordering, need be detected. A technique for
measurement of the CP-violating weak decay parameter sin(2beta) is described
which exploits this observation.Comment: 9 pages postscript, also available through
http://w4.lns.cornell.edu/public/CLN
Applicability of Perturbative QCD to Decays
We examine the applicability of perturbative QCD to meson decays into
mesons. We find that the perturbative QCD formalism, which includes Sudakov
effects at intermediate energy scales, is applicable to the semi-leptonic decay
, when the meson recoils fast. Following this conclusion, we
analyze the two-body non-leptonic decays and . By
comparing our predictions with experimental data, we extract the matrix element
.Comment: 18 pages in Latex, figures are available upon reques
UNIVERSITI SAINS MALAYSIA First Semester Examination 2016/2017 Academic Session December 2016 / January 2017 EBB 42713 — Technology and Application of Engineering Polymer [Teknologi dan Penggunaan Polimer Kejuruteraanl Duration : 3 hours [Masa : 3 jam]
Figure 1: The UltraHaptics system. Left: the hardware. Centre: a simulation of two focal points, with colour representing phase and brightness representing amplitude. Right: receiving two independent points of feedback while performing a pinch gesture. We introduce UltraHaptics, a system designed to provide multi-point haptic feedback above an interactive surface. UltraHaptics employs focused ultrasound to project discrete points of haptic feedback through the display and directly on to users ’ unadorned hands. We investigate the desirable properties of an acoustically transparent display and demonstrate that the system is capable of creating multiple localised points of feedback in mid-air. Through psychophysical experiments we show that feedback points with different tactile properties can be identified at smaller separations. We also show that users are able to distinguish between different vibration frequencies of non-contact points with training. Finally, we explore a number of exciting new interaction possibilities that UltraHaptics provides. Author Keywords Haptic feedback; touch screens; interactive tabletops
Improving Influenza and Tdap Vaccination during Pregnancy: A Cluster-randomized Trial of a Multi-component Antenatal Vaccine Promotion Package in Late Influenza Season
Background Evidence-based interventions to improve influenza vaccine coverage among pregnant women are needed, particularly among those who remain unvaccinated late into the influenza season. Improving rates of antenatal tetanus, diphtheria and acellular pertussis (Tdap) vaccination is also needed
Di-electron Widths of the Upsilon(1S,2S,3S) Resonances
We determine the di-electron widths of the Upsilon(1S), Upsilon(2S), and
Upsilon(3S) resonances with better than 2% precision by integrating the
cross-section of e+e- -> Upsilon over the e+e- center-of-mass energy. Using
e+e- energy scans of the Upsilon resonances at the Cornell Electron Storage
Ring and measuring Upsilon production with the CLEO detector, we find
di-electron widths of 1.354 +- 0.004 (stat) +- 0.020 (syst) keV, 0.619 +- 0.004
+- 0.010 keV, and 0.446 +- 0.004 +- 0.007 keV for the Upsilon(1S), Upsilon(2S),
and Upsilon(3S), respectively.Comment: 9 pages, 4 figures, also available through
http://www.lns.cornell.edu/public/CLNS/2005/, published in PRL; corrected
numerical values in abstrac
Search for Lepton Flavor Violation in Upsilon Decays
In this Letter we describe a search for lepton flavor violation (LFV) in the
bottomonium system. We search for leptonic decays of Upsilon(nS)(n=1,2, and 3)
into muon and tau using the data collected with the CLEO III detector. We
identify the tau lepton using its leptonic decay into electron and utilize
multidimensional likelihood fitting with PDF shapes measured from independent
data samples. We report our estimates of 95% CL upper limits on LFV branching
fractions of Upsilon mesons. We interpret our results in terms of the exclusion
plot for the energy scale of a hypothetical new interaction versus its
effective LFV coupling in the framework of effective field theory.Comment: 10 pages, 3 figures, available through
http://www.lns.cornell.edu/public/CLNS/, submitted to PR
Confirmation of the Y(4260) Resonance Production in ISR
Using 13.3 fb^-1 of e+e- collision data taken in the Upsilon(1S-4S) region
with the CLEO III detector at the CESR collider, a search has been made for the
new resonance Y(4260) recently reported by the BaBar Collaboration. The
production of Y(4260) in initial state radiation (ISR), and its decay into
pi+pi-J/psi are confirmed. A good quality fit to our data is obtained with a
single resonance. We determine M(Y(4260))=(4284+17-16(stat)+-4(syst)) MeV/c^2,
Gamma(Y(4260))=(73+39-25(stat)+-5(syst)) MeV/c^2, and
Gamma_ee(Y(4260))xBr(Y(4260)->pi+pi-J/psi)=(8.9+3.9-3.1(stat)+-1.9(syst))
eV/c^2.Comment: 8 pages postscript,also available through
http://www.lns.cornell.edu/public/CLNS/2006/, Submitted to PRD (Rapid Comm.
Measurement of Absolute Hadronic Branching Fractions of D Mesons and e^+ e^- --> D D-bar Cross Sections at the psi(3770)
Using 281 /pb of e^+ e^- collisions recorded at the psi(3770) resonance with
the CLEO-c detector at CESR, we determine absolute hadronic branching fractions
of charged and neutral D mesons using a double tag technique. Among
measurements for three D^0 and six D^+ modes, we obtain reference branching
fractions B(D^0 --> K^-pi^+) = (3.891 +- 0.035 +- 0.059 +- 0.035)% and B(D^+
--> K^-pi^+pi^+) = (9.14 +- 0.10 +- 0.16 +- 0.07)%, where the first uncertainty
is statistical, the second is all systematic errors other than final state
radiation (FSR), and the third is the systematic uncertainty due to FSR. We
include FSR in these branching fractions by allowing for additional unobserved
photons in the final state. Using an independent determination of the
integrated luminosity, we also extract the cross sections sigma(e+e- --> D^0
D^0-bar) = (3.66+- 0.03 +- 0.06) nb and sigma(e+e- --> D^+ D^-) = (2.91+- 0.03
+- 0.05) nb at a center of mass energy, E_cm = 3774 +- 1 MeV.Comment: 47 pages, postscript also available through this
http://www.lns.cornell.edu/public/CLNS/2007/, to be published in PRD, updated
branching fractions using B(KS0 --> pi+ pi-) from PDG 2007, and updated text
in response to the PRD reviewe
Measurement of the Total Hadronic Cross Section in e+e- Annihilations below 10.56 GeV
Using the CLEO III detector, we measure absolute cross sections for e+e- -->
hadrons at seven center-of-mass energies between 6.964 and 10.538 GeV. The
values of R, the ratio of hadronic and muon pair production cross sections, are
determined within 2% total r.m.s. uncertainty.Comment: 17 pages postscript,also available through
http://www.lns.cornell.edu/public/CLNS/2007/, Submitted to PR
Search for psi(2S)--> eta_c pi^+ pi^- pi^0
Using 5.63 pb^-1 of data accumulated at the psi(2S) resonance with the CLEO
III and CLEO-c detectors corresponding to 3.08 million psi(2S) decays, a search
is performed for the decay psi(2S) -> eta_c pi^+pi^-pi^0 to test a theoretical
prediction based upon the assumption that the c \bar c pair in the psi(2S) does
not annihilate directly into three gluons but rather survives before
annihilating. No signal is observed, and a combined upper limit from six eta_c
decay modes is determined to be B(psi(2S) -> eta_c pi^+pi^-pi^0) < 1.0 x 10^-3
at 90% C.L. This upper limit is about an order of magnitude below the
theoretical expectation.Comment: 8 pages postscript,also available through
http://www.lns.cornell.edu/public/CLNS/2006
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