BALANCE OF TRANSVERSE MOMENTUM OF HADRONS PRODUCED IN DEEP INELASTIC MUON PROTON SCATTERING

Data are presented on the balance of transverse momenta of final state charged hadrons in 280 GeV muon-proton scattering. In particular the way in which the transverse momentum of either leading particles (z > 0.5) f high pT particles (pT2 > 2 GeV2) is compensated by further hadrons in the forward hemisphere is studied. The results are consistent with a QCD based model. The agreement is achieved by including in the model the emission of soft gluons and assuming that the partons have a distribution of primordial transverse momentum with 〈kT2〉 {reversed tilde equals} 0.2 GeV2, a value considerably less then found in previous analyses. © 1982

AN EXPERIMENTAL LIMIT ON THE INTRINSIC CHARM COMPONENT OF THE NUCLEON

Charm production has been studied through multimuon events produced in 250 GeV μ+-interactions. The measured dimuon cross section is in agreement with the photon gluon fusion model at low values of Bjorken x within statistical and systematic errors. At larger values of xBi the data do not support the magnitude of intrinsic charm used to explain hadro-production of charm. Upper limits on the intrinsic charm content of the nucleon are derived from the data. © 1982

MEASUREMENT OF THE PROTON STRUCTURE FUNCTION F(2) IN MUON - HYDROGEN INTERACTIONS AT 120-GeV AND 280-GeV

The proton structure function F2 has been measured in the range 2.5 {slanted equal to or less-than} Q2 {slanted equal to or less-than} 170 GeV2and 0.03 {slanted equal to or less-than} x {slanted equal to or less-than} 0.65. Scaling violation is clearly seen in the data. Results of fits to leading-order QCD are presented, together with values of the scale-breaking parameter λ. © 1981

QCD ANALYSIS OF THE STRUCTURE FUNCTION F2 IN MUON NUCLEON SCATTERING

A QCD analysis in leading and next to leading order of the structure function F2 measured in deep inelastic muon nucleon scattering is presented. Taking into account several phenomenological uncertainties, including the gluon description and the charm contribution, fits to the data give values of the QCD scale parameter ΛLO in the range 7--250 MeV. A consistent description of muon scattering and lower Q2 electron scattering requires the presence of higher twist 1/Q2 contributions to the scale breaking which are then determined as a function of x from the data. © 1982

A LARGE MAGNETIC SPECTROMETER SYSTEM FOR HIGH-ENERGY MUON PHYSICS

The European Muon Collaboration has built a large magnetic spectrometer system for deep inelastic muon scattering experiments at the CERN SPS muon beam. The general characteristics of the apparatus - composed of a target of either liquid hydrogen or deuterium, or iron plus scintillator, followed by a large magnet with wire chambers before and after it for precise angle and momentum measurement, a muon identifier, large trigger hodoscopes, and hadron identifiers - are explained and each part is described in some detail. The main features of the data-acquisition and apparatus-monitoring systems and of the off-line event reconstruction are given. © 1981

MEASUREMENT OF THE Q**2, x AND W**2 DEPENDENCE OF SINGLE HADRON PRODUCTION IN DEEP INELASTIC MUON SCATTERING

Measurements are presented of the distributions in scaled energy of the hadrons produced in high energy muon scattering. The observed dependence on x (non-factorisation) and Q2 (scaling violation) is similar to that expected from next to leading order QCD calculations. These variations in the data can be equivalently represented by a dependence on the single variable W2. © 1982

MEASUREMENT OF THE DEUTERON STRUCTURE FUNCTION F2 AND A COMPARISON OF PROTON AND NEUTRON STRUCTURE

The deuteron structure function F2d has been measured in 280 GeV μ+ d interactions. Existing measurements of F2p, made with the same apparatus, are used to calculate F2p-F2n and F2n F2p. The ratio F2n F2p has a similar x dependence to that of earlier measurements at lower Q2. © 1983