118566473
B Physics at threshold: Recent results from ARGUS and CLEO-II
17397470
Inclusive decays of B mesons to charmonium.
We have used the CLEO-II detector at the Cornell Electron Storage Ringe (CESR) to study the inclusive production of charmonium mesons in a sample of 2.15 million {ital B{bar B}} events. We find inclusive branching fractions of (1.12{plus_minus}0.04{plus_minus}0.06)% for {ital B}{r_arrow}{ital J}/{psi}{ital X}, (0.34{plus_minus}0.04{plus_minus}0.03)% for {ital B}{r_arrow}{psi}{prime}{ital X}, and (0.40{plus_minus}0.06{plus_minus}0.04)% for {ital B}{r_arrow}{chi}{sub {ital c}1}{ital X}. We also find some evidence for the inclusive production of {chi}{sub {ital c}2}, and set an upper limit for the branching fraction of the inclusive decay {ital B}{r_arrow}{eta}{sub {ital c}}{ital X} of 0.9% at 90% confidence level. Momentum spectra for inclusive {ital J}/{psi}, {psi}{prime}, and {chi}{sub {ital c}1} production are presented. These measurements are compared to theoretical calculations.
15188676
Calibration and performance of the MARK II drift chamber vertex detector
We have calibrated and studied the performance of the MARK II drift chamber vertex detector with cosmic ray tracks collected with the chamber inside the MARK II detector at the SLC. The chamber achieves 30 {mu}m impact parameter resolution and 500 {mu}m track-pair resolution using CO{sub 2}/C{sub 2}H{sub 6}H{sub 6}(92/8) at 2 atmospheres pressure. The chamber has successfully recorded Z{sup 0} decays at the SLC, and resolved tracks in dense hadronic jets with good efficiency and high accuracy. 5 refs., 13 figs.
35600922
Measurement of the branching fraction for D+-->K- pi + pi +
Using the CLEO-II detector at CESR we have measured the ratio of branching fractions, B(D+ → K−π+π+)/B(D0 → K−π+) = 2.35 ± 0.16 ± 0.16. Our recent measurement of B(D0 → K−π+) then gives B(D+ → K−π+π+) =
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.
122233998
Comparison and summary of tau topological branching fractions
After nearly two decades of work on topological branching fractions, it appears that an experimental consensus is forming. The new world average is 14.54 ± 0.20.
119328153
NNLO corrections to massive lepton-pair production in longitudinally polarized proton–proton collisions
We present the full next-to-next-to-leading order (NNLO) coefficient func- tions for the polarized cross section d�σ/dQ for the Drell-Yan process p+p → l + l − + ' X ' . HereXdenotes any inclusive hadronic state and Q represents the invariant mass of the lepton pair. All QCD partonic subprocesses have been included provided the lepton pair is created by a virtual photon, which is a valid approximation for Q < 50 GeV. Unlike the differential distribu- tion w.r.t. transverse momentum the dominant subprocess for the integrated cross section is given by q + ¯ q → γ ∗ + ' Xand its higher order corrections so that massive lepton pair production provides us with an excellent tool to measure the polarized anti-quark densities. Our calculations are carried out using the method of n-dimensional regularization by making a special choice for the γ5 matrix. We give predictions for double longitudinal spin asymmetry measurements at the RHIC.
1705219
Heavy-quark correlations in deep inelastic scattering
Abstract We discuss some results for heavy quark correlations in next-to-leading order in deep inelastic electroproduction.
119359091
Deep-inelastic production of heavy quarks
Deep-inelastic production of heavy quarks at HERA, especially charm, is an excellent signal to measure the gluon distribution in the proton at small x values. By measuring various dierential distributions of the heavy quarks this reaction permits additional more incisive QCD analyses due to the many scales present. Furthermore, the relatively small mass of the charm quark, compared to the typical momentum transfer Q, allows one to study whether and when to treat this quark as a parton. This reaction therefore sheds light on some of the most fundamental aspects of perturbative QCD. We discuss the above issues and review the feasibility of their experimental investigation in the light of a large integrated luminosity.
118910620
Differential Cross-Sections for Higgs Production
We review recent theoretical progress in evaluating higher order QCD corrections to Higgs boson differential distributions at hadron–hadron colliders.
119446494
QCD threshold corrections to di-lepton and Higgs rapidity distributions beyond N2LO
Abstract We present threshold enhanced QCD corrections to rapidity distributions of di-leptons in the Drell–Yan process and of Higgs particles in both gluon fusion and bottom quark annihilation processes using Sudakov resummed cross sections. We have used renormalisation group invariance and the mass factorisation theorem that these hard scattering cross sections satisfy as well as Sudakov resummation of QCD amplitudes. We find that these higher order threshold QCD corrections stabilise the theoretical predictions under scale variations.