D. M. Lee

The L3 silicon microvertex detector

Abstract The design and construction of the silicon strip microvertex detector (SMD) of the L3 experiment at LEP are described. We present the sensors, readout electronics, data acquisition system, mechanical assembly and support, displacement monitoring systems and radiation monitoring system of the recently installed double-sided, double-layered SMD. This detector utilizes novel and sophisticated techniques for its readout.

Measurement of Angular Distributions of Drell-Yan Dimuons in p + d Interaction at 800 GeV/c

We report a measurement of the angular distributions of Drell-Yan dimuons produced using an 800 GeV/c proton beam on a deuterium target. The muon angular distributions in the dilepton rest frame have been measured over the kinematic range 4.5<m{mu mu}<15 GeV/c{2}, 0<p{T}<4 GeV/c, and 0<x{F}<0.8. No significant cos2phi dependence is found in these proton-induced Drell-Yan data, in contrast with the situation for pion-induced Drell-Yan data. The data are compared with expectations from models which attribute the cos2phi distribution to a QCD vacuum effect or to the presence of the transverse-momentum-dependent Boer-Mulders structure function h{1}{perpendicular}. Constraints on the magnitude of the sea-quark h{1}{perpendicular} structure functions are obtained.

Improved measurement of the anti-d / anti-u asymmetry in the nucleon sea

Measurements of the ratio of Drell-Yan yields from an 800 \rm{GeV/c} proton beam incident on liquid hydrogen and deuterium targets are reported. Approximately 360,000 Drell-Yan muon pairs remained after all cuts on the data. From these data, the ratio of anti-down (

Measurement of Upsilon production for p + p and p + d interactions at 800 GeV/c.

\bar{d}

The L3 Silicon Microvertex Detector: installation and results on 1993 performance

) to anti-up (

Reaction 58Ni(π+,2p) at 160 MeV

\bar{u}

Measurement of the branching ratio for the rare decay KL0--> micro+ micro-

) quark distributions in the proton sea is determined over a wide range in Bjorken-

Pion non-analog double charge exchange: 16O(π+, π−)16Ne☆

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Reaction /sup 58/Ni(. pi. /sup +/,2p-italic) at 160 MeV

. These results confirm previous measurements by E866 and extend them to lower

ASL, ALL and ANO for NN → πD at 492, 729 and 796 MeV

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