Showing papers on "Parton published in 1982"
TL;DR: In this paper, the authors define parton distribution and decay functions in QCD and prove some of their basic properties, such as renormalization, light-cone expansions and sum rules.
772 citations
TL;DR: In this article, the spectrum of charged leptons in semileptonic B and D decays is reanalyzed and the effects of soft gluons are studied and their contribution is resummed in leading double logarithmic approximation.
386 citations
TL;DR: An overall view of the physics of QCD in the perturbative domain is presented in a form that could be of use both as an introduction to the subject with its main lines of current development and as a reference review text for more expert readers as well.
370 citations
CERN1
TL;DR: In this article, a summary of QCD formulae describing the effects of scaling violation in leptonhadron processes, with the inclusion of recently derived higher order corrections, is presented, and a comparative analysis of various processes as well as an independent analysis of each of them is possible.
Abstract: We present a summary of QCD formulae describing the effects of scaling violation in leptonhadron processes, with the inclusion of recently derived higher order corrections. Deep inelastic leptoproduction, one-hadron inclusive distributions in leptoproduction and ine
+
e
− annihilation and Drell-Yan processes are discussed in detail. Higher order corrections to parton densities, fragmentation functions and to lepton-parton cross-sections in the above processes are presented in a common factorization scheme, so that a comparative analysis of various processes as well as an independent analysis of each of them is possible. A discussion of the various scheme dependences at next-to-leading level is also included.
303 citations
CERN1
TL;DR: In this article, the power corrections to deep inelastic lepton-hadron scattering in QCD were calculated in terms of Feynman graphs, introducing a transverse basis of parton correlation functions as a useful language.
183 citations
01 Aug 1982
TL;DR: In this article, it was shown that high energy hadron-hadron collisions with high asscoiated multiplicity and with transverse energy dET/dy in excess of 10 GeV per unit rapidity, it is possible that quark-gluon plasma is produced in the collision.
Abstract: Hi& energy quarks and gluons propagating through quark-gluon plasma suffer differential energy loss via elastic scattering from quanta in the plasma. lhis mechanism is very similar in structure to ionization loss of charged particles in ordinary matter. 'ihe dE/dx is roughly proportional to the square of the plasma temperature. For hadron-hadron collisions with high asscoiated multiplicity and with transverse energy dET/dy in excess of 10 GeV per unit rapidity, it is possible that quark-gluon plasma is produced in the collision. If so, a produced secondary high-p, quark or gluon might lose tens of GeV of its initial transverse momentum while plowing through quark-gluon plasma produced in its local environment. High energy hadron jet experiments should be analysed as function of associated multiplicity to search for this effect. An interesting signature may be events in which the hard collision occurs near the edge of the overlap region, with one jet escaping without absorption and the other fully absorbed.
167 citations
TL;DR: In this article, the influence of coherence in a soft parton bremsstrahlung on hadron spectra in jets is discussed and a simple functional method for calculation of different inclusive parton distributions in the “plateau” region is presented.
94 citations
TL;DR: In this paper, the average charge multiplicities and dispersions in protonproton and antiproton-proton interactions up to SPS collider energies in the framework of a multi-chain dual parton model were computed.
83 citations
CERN1
TL;DR: The Drell-Yan process is an electromagnetic effect in which a quark and antiquark from a pair of interacting hadrons annihilate to give a lepton pair as mentioned in this paper.
Abstract: The Drell-Yan process is an electromagnetic effect in which a quark and antiquark from a pair of interacting hadrons annihilate to give a lepton pair. A brief description of hadron structure and the parton model is given to provide a necessary background. Then the general features of lepton pair production are described and the Drell-Yan formalism is set up. Experimental techniques are described next; these are rather simple since it is only necessary to detect the leptons emitted from hadron interactions. Predictions and tests of the basic model show that, in general, it works well. The anomalous features are the overall cross-section level (high by a factor of 2) and the unexpectedly large mean transverse momenta. Quantum chromodynamics (QCD) offers the explanation of these anomalies, and measurements of dilepton production provide important quantitative tests of QCD. Such measurements have also been used to determine nucleon structure functions and, for the first time, meson structure functions.
67 citations
TL;DR: In this paper, a full Monte Carlo program for hadron-hadron interactions at large pT has been set up which includes, besides the QCD hard scattering process and the fragmentation a la Field and Feynman of the final quanta, also QCD radiation off the initial quanta and beam jet fragmentation.
61 citations
TL;DR: In this article, the influence of coherence in a soft parton bremsstrahlung on hadron spectra in jets is discussed and a simple functional method for calculation of different inclusive parton distributions in the “plateau” region is presented.
Abstract: The influence of coherence in a soft parton bremsstrahlung on hadron spectra in jets is discussed. We present a simple functional method for calculation of different inclusive parton distributions in the “plateau” region. Inclusive parton cross sections, spectra, multiplicities, energy and angular correlations, etc. are derived in the Double Logarithmic approximation.
TL;DR: In this paper, the density distribution of particles produced in a high-energy nucleus-nucleus interaction, in the framework of the dual-parton model, is computed.
TL;DR: In this paper, a multi-pomeron exchange model was proposed for ISR and SPS colliders in terms of a dual parton framework, where the particle rapidity distributions, energy dependence of the central plateau, ratio of particle densities in proton-proton and antiprotonproton scattering and non-diffractive multiplicities were successfully accounted for in the model.
TL;DR: In this article, the authors discuss scaling and the dimensional counting rules, the parton structure of hadrons, and the model for large momentum transfer processes, including scaling violations, and then turn their attention to Regge theory and its applications in exclusive and inclusive reactions.
Abstract: The mechanisms of hadron scattering at high energies are reviewed in an introductory fashion, but from a modern standpoint in which the authors try to combine the ideas of the parton model and quantum chromodynamics (QCD) with Regge theory and phenomenology. After a brief introduction to QCD and the basic features of hadron scattering data, the authors discuss scaling and the dimensional counting rules, the parton structure of hadrons, and the parton model for large momentum transfer processes, including scaling violations. Hadronic jets and the use of parton ideas in soft scattering processes are examined, and the authors then turn their attention to Regge theory and its applications in exclusive and inclusive reactions, stressing the relationship to parton exchange. The mechanisms of hadron production which build up cross-sections, and hence the underlying Regge singularities, and the possible overlap of Regge and scaling regions are discussed. The key to understanding hadron reaction mechanisms seems to lie in the marriage of Regge theory with QCD.
TL;DR: In this article, the authors studied the production of direct photons in e + e − annihilation e+ e − → γ + hadrons, where the high-energy photon is emitted at a large angle to a hadron jet or is a fragment of the jet itself.
TL;DR: In this paper, the topology of hadronic e + e − annihilation events has been analyzed using the sphericity tensor and a cluster method, which yields good agreement with the data.
TL;DR: In this article, a way to distinguish experimentally between primordial and soft gluon effects is given, and the forward-backward asymmetry in the hadronic energy flow predicted by perturbative QCD is, at presently available energies, difficult to observe in the final state of observable particles due to the fragmentation of the jets.
TL;DR: In this article, the transverse momentum properties of Drell-Yan pairs produced in hadronic collisions are analyzed in QCD by combining the soft gluon description at low p⊥ with hard parton effects at high p ⊥.
TL;DR: In this article, the authors found evidence for correlations in rapidity and azimuthal angle between high transverse momentum charged particles at the centre of mass energy 540 GeV from the CERN p p p collider.
TL;DR: An annotated bibliography of references to quarks and related topics in elementary particle physics, as well as to the role of quarks in areas outside nuclear physics, such as nuclear physics and astrophysics and cosmology is given in this article.
Abstract: Quarks as fundamental constituents of hadrons play a central role in elementary particle physics. We give an annotated bibliography of references to quarks and related topics in elementary particle physics, as well as to the role of quarks in areas outside elementary particle physics, such as nuclear physics, and astrophysics and cosmology. We label references E (elementary), I (intermediate), and A (advanced) to guide the reader. Articles selected for incorporation in a reprint volume (to be published separately by the American Association of Physics Teachers) are indicated by an an asterisk. A short list of particularly helpful elementary and intermediate references is indicated by a star.
TL;DR: In this article, a phenomenological successful dual fragmentation model is extended to events with unusually large particle multiplicities with the object to explain data obtained with a large transverse energy trigger.
Abstract: A phenomenological successful dual fragmentation model is extended to events with unusually large particle multiplicities with the object to explain data obtained with a large transverse energy trigger. The concern of this investigation is a transition region: the dominant production mechanism is still soft and the final state still possesses an approximate one-dimensional structure, but the contributions from multiple pomeron exchange can no longer be ignored.
TL;DR: In this article, the authors calculate the ratioR in the framework of Anisotropic Chromo-Dynamics (ACD), a recently proposed approach to strong interactions, and show that asymptotically the Quark Parton Model value is recovered.
Abstract: We calculate the ratioR in the framework of Anisotropic Chromo-Dynamics (ACD), a recently proposed approach to strong interactions, and we show that asymptotically the Quark Parton Model value is recovered. Scaling violations due to the quark-masses and to the structure of the
$$q\bar q$$
-potential are also calculated.
TL;DR: In this article, the authors examined the distribution of charge versus rapidity in the framework of available parton models for multiparticle production in hadron-hadron collisions, and showed that the two-chain Pomeron contribution with a dual topological unitarization scheme is able to describe the recently measured data on charge distributions in high energypp and πp collisions.
Abstract: The distribution of charge versus rapidity is examined in the framework of available parton models for multiparticle production in hadron-hadron collisions. Fragmentation models with a twochain Pomeron contribution (based on the dual topological unitarization scheme) are shown to describe rather well the recently measured data on charge distributions in high energypp and πp collisions (140 GeV/c≦pLAB≦360 GeV/c). Carefully measured charge distributions at still higher energies which will be accessible in the near future offer a possibility of distinguishing between some of the current theoretical approaches.
CERN1
TL;DR: In this paper, the balance of transverse momenta of final state charged hadrons in 280 GeV muon-proton scattering was studied. And the results were consistent with a QCD based model.
TL;DR: In this article, the Parisi and Petronzio LLA result for the QCD transverse momentum distribution of Drell-Yan pairs at pT⪡Q takes into account the non-singlet contribution only and totally neglects non-abelian effects due to the singlet contribution.
TL;DR: In this article, the effects of quark mass dependence in the momentum subtracted beta function and anomalous dimensions of quantum chromodynamics are investigated, and the sensitivity of predicted quark and gluon moments for deep inelastic scattering to changes in the prescriptions used in defining the mass-dependent renormalization group parameters is examined.
TL;DR: In this article, various models of cumulative production of mesons were compared qualitatively with experimental data, and the experimental data was used to compare different models of meson production with various experimental data sets.
TL;DR: In this article, the dual parton fragmentation model for low p T multiparticle production in hadronic collisions successfully describes recently measured two particle inclusive distributions into π + π+, π plus π − and π− π-pair.
TL;DR: In this paper, a calculation of all two-loop graphs in QCD involving the interactions of virtual gluons with the spectator quark in the process quark + hadron → lepton pair + anything is presented.