236 research outputs found
Review of Two-Photon Interactions
Presented are recent results of two-photon interactions. Topics inlcude
photon structure functions, inclusive hadron production, differential cross
sections derived from tagged 2-photon fusion events and results in exclusive
hadron production, particularly the observations of the eta_c prime.Comment: 5 pages, Latex, To be published in proceedings to CIPANP held in NY
city May 200
Exploring the Charm Sector with CLEO-c
The CLEO collaboration proposes to explore the charm sector starting early
2003. It is foreseen to collect on the order of 6 million D D-bar pairs, 300000
Ds Ds-bar pairs at threshold and one billion J/psi decays. High precision charm
data will enable us to validate upcoming Lattice QCD calculations that are
expected to produce 1-3% errors for some non-perturbative QCD quantities. These
can then be used to improve the accuracy of CKM elements. The radiative J/psi
decays will be the first high statistics data set well suited for meson
spectroscopy between 1600 and 3000 MeV.Comment: 10 pages, Latex, to be published in proceedings of Hadron 2001
Protvino Added Reference to Detector Section. Corrected typo in table
Measurement of HQET Parameters and CKM Matrix Elements
The determination of CKM matrix elements in the b-sector is discussed,
emphasizing the new measurements of Vub and Vcb by the CLEO collaboration.Comment: 4 pages, Latex, to be published in proceedings of Hadron 2001 at
Protvin
When can unlabeled data improve the learning rate?
Göpfert C, Ben-David S, Bousquet O, Gelly S, Tolstikhin I, Urner R. When can unlabeled data improve the learning rate? In: Conference on Learning Theory (COLT). 2019
The Muon Anomalous Magnetic Moment and the Standard Model
The muon anomalous magnetic moment measurement, when compared with theory,
can be used to test many extensions to the standard model. The most recent
measurement made by the Brookhaven E821 Collaboration reduces the uncertainty
on the world average of a_mu to 0.7 ppm, comparable in precision to theory.
This paper describes the experiment and the current theoretical efforts to
establish a correct standard model reference value for the muon anomaly.Comment: Plenary Talk; PANIC'02 XVI Particles and Nuclear International
Conference, Osaka, Japan; Sept. 30 - Oct. 4, 2002; Report describes the
published 0.7 ppm result and updates the theory statu
Status Of The FAIR Synchrotron Projects SIS18 And SIS100
A large fraction of the program to upgrade the existingheavy ion synchrotron SIS18 as injector for the FAIR synchrotron SIS100 has been successfully completed. With the achieved technical status, a major increase of theaccelerated number of heavy ions could be reached. Thenow available performance especially demonstrates thefeasibility of high intensity beams of medium charge stateheavy ions with a sufficient control of the dynamicvacuum and connected charge exchange loss. Two furtherupgrade measures, the installation of additional magneticalloy (MA) acceleration cavities and the exchange of themain dipole power converter, are presently beingimplemented. For the FAIR synchrotron SIS100, theprocurement of all major components with longproduction times has been started. With the delivery andtesting of several pre-series components, the phase ofoutstanding technical reserach and developments could becompleted and the readiness for series productionachieved
Search for CP violation in D+→ϕπ+ and D+s→K0Sπ+ decays
A search for CP violation in D + → ϕπ + decays is performed using data collected in 2011 by the LHCb experiment corresponding to an integrated luminosity of 1.0 fb−1 at a centre of mass energy of 7 TeV. The CP -violating asymmetry is measured to be (−0.04 ± 0.14 ± 0.14)% for candidates with K − K + mass within 20 MeV/c 2 of the ϕ meson mass. A search for a CP -violating asymmetry that varies across the ϕ mass region of the D + → K − K + π + Dalitz plot is also performed, and no evidence for CP violation is found. In addition, the CP asymmetry in the D+s→K0Sπ+ decay is measured to be (0.61 ± 0.83 ± 0.14)%
Differential branching fraction and angular analysis of the decay B0→K∗0μ+μ−
The angular distribution and differential branching fraction of the decay B 0→ K ∗0 μ + μ − are studied using a data sample, collected by the LHCb experiment in pp collisions at s√=7 TeV, corresponding to an integrated luminosity of 1.0 fb−1. Several angular observables are measured in bins of the dimuon invariant mass squared, q 2. A first measurement of the zero-crossing point of the forward-backward asymmetry of the dimuon system is also presented. The zero-crossing point is measured to be q20=4.9±0.9GeV2/c4 , where the uncertainty is the sum of statistical and systematic uncertainties. The results are consistent with the Standard Model predictions
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