120135663
Studies of tau decay modes with K0 mesons from CLEO
We examine five final states involving K 0 mesons, presenting branching fractions for the decays τ → K 0 πν τ , τ → K 0 ππ 0 ν τ , τ → K 0 Kν τ , τ → K 0 Kπ 0 ν τ , and τ → K s K s hν τ . The mass spectra provide evidence for the dominant role of K * in Kπ decays and K 1 in Kππ modes. We find evidence for a significant K * K contribution to the KKπ decays.
120150178
Measurement of anomalous muon pair production in electron-positron annihilations
We have observed 16 events of the type ..mu../sup +/..mu../sup -/ + (missing energy and momentum) from e/sup +/e/sup -/ annihilations at center-of-mass energies between 6.4 and 7.4 GeV. Taking into account QED backgrounds, we find an excess of 11 anomalous dimuon events. If these are attributed to the production and subsequent decay of a pair of heavy leptons L/sup + -/, we obtain the muonic braching ratio B ((L/sup +/ ..-->.. ..mu../sup +/..nu../sub ..mu../nu-bar/sub L/)/ (L/sup +/ ..-->.. all)) = 0.22/sup +0.07//sub -0.08/.
115309491
Experimental results for charmless hadronic B decays
94362727
Studies of radiation damage to CAMEX64 preamplifiers exposed to gamma -rays at the Cornell High Energy Synchrotron Source
CAMEX64 preamplifiers, developed for use in the readout of silicon strip detectors, have been exposed to well-measured doses of monochromatic gamma -rays from the Cornell High Energy Synchrotron Source (CHESS), and measurements of the resulting radiation damage have been made. Silicon strip detectors with their associated CAMEXes will be installed close to the interaction region in the CLEO experiment at Cornell University, where they will be exposed to both charged particle and photon fluences. Powered and unpowered CAMEXes were irradiated and after each exposure measurements of pedestals, gains, and coherent and incoherent noise were made until the devices could no longer be read out. Results are presented for noise and gain degradation as a function of dose. Using well-controlled and calibrated 20 keV synchrotron radiation, failure begins at 20 krad in powered CAMEXes and between 60 and 120 krad in unpowered CAMEXes. These failure levels are considerably larger than the projected radiation dose.<<ETX>>
124046826
CHARMLESS HADRONIC B DECAYS WITH THE FULL CLEO DATA SAMPLE
118236755
Recent Results in Charmless Hadronic B Decays from BABAR
We report results from five analyses based on data taken with the BABAR detector at the PEP-II asymmetric e{sup +}e{sup -} collider. Included are branching fraction measurements for many B-meson decays involving {eta}, {eta}{prime}, {omega}, {phi} or a{sub 0} mesons and the final state K{sub s}{sup 0}{pi}{sup +}{pi}{sup -}, and a full angular analysis of the decay B{sup 0} {yields} {phi}K*{sup 0}.
119575829
On the heavy-quark content of the nucleon☆
Abstract Recently QCD corrections to the light (massless)-quark and heavy (massive)-quark structure functions of the proton have been computed up to O ( α s 2 ). Using these results we present the O ( α s 2 ) contributions to the ratio of the heavy-quark content of the nucleon with respect to the sum of the heavy-quark plus light-quark content for charm and bottom quarks. We find that, at small x , the heavy-quark fraction is suprisingly large and remarkably insensitive to changes in the mass factorization scale and/or the choice of parton densities.
120089418
Electron Signals from Heavy Lepton Cascade Decays
119326541
Determination of the asymptotic behaviour of the heavy flavour coefficient functions in deep inelastic scattering
Abstract Using renormalization group techniques we have derived analytic formulae for the next-to-leading order heavy-quark coefficient functions in deep inelastic lepton hadron scattering. These formulae are only valid in the kinematic regime Q 2 ⪢ m 2 , where Q 2 and m 2 stand for the masses squared of the virtual photon and heavy quark respectively. Some of the applications of these asymptotic formulae will be discussed.
119411437
Comparison between variable flavor number schemes for charm quark electroproduction
A comparison is made between two variable flavor number schemes which describe charm quark production in deep inelastic electron-proton scattering. In these schemes the coefficient functions are derived from mass factorization of the heavy quark coefficient functions presented in a fixed flavor number scheme. Since the coefficient functions in the variable flavornumber schemes have to be finite in the limit m → 0 we have defined a prescription for those processes where the virtual photon is attached to a light quark. Furthermore one has to construct a parton density set with four active flavors (u,d,s,c) out of a set which only contains three light flavors (u,d,s). In order � 2 the two sets are discontinuous at µ = mc which follows from mass factorization of the heavy quark coefficient functions. The charm component ofthe structure function F2,c is insensitive to the different variable flavor number schemes. In particular in the threshold region they both agree with the description in fixed order perturbation theory presented in a three flavor scheme. However one version does not lead to a correct description of the threshold behavior of the longitudinal structure function FL,c. This happens when one requires a non-vanishing zeroth order longitudinal coefficient function.
118976257
Quarks and Antiquarks in Nuclei
The Chiral Quark-Soliton model provides the quark and antiquark substructure of the nucleon, which is embedded in nuclear matter. This provides a new way to asses the effects of the nuclear medium on the nucleon. We calculate nuclear binding and saturation, describe the European Muon Collaboration (EMC) effect consistently with Drell-Yan experiments, and predict modifications to the polarized parton distributions. We also calculate the electromagnetic form factors of a bound proton, and find significant modifications of the electromagnetic form factors in the nuclear environment. In every case, the properties of the sea of quark-antiquark pairs in the nucleon are very important, and serve to mitigate the valence quark effect. The changes in the sea quarks when the nucleon is immersed in the nuclear medium are the primary mode by which consistency is maintained with experimental constraints (Drell-Yan data, magnetic moment), while still maintaining a significant effect needed to explain the deep inelastic scattering and polarization transfer data.