Showing papers on "Parton published in 1976"
CERN1
TL;DR: In this paper, the authors studied the deviations to be expected at high energies from the recently observed two-jet structure of hadronic final states in e + e − annihilation, and suggested that hard gluon bremsstrahlung may be the dominant source of hadrons with large momenta transverse to the main jet axes.
253 citations
TL;DR: The quark-parton model is used to study neutrino scattering in the case where the mass of a heavy, produced quark is not neglected as discussed by the authors, and the masses of produced heavy quarks are estimated.
Abstract: The quark-parton model is used to study neutrino scattering in the case where the mass of a heavy, produced quark is not neglected. Evidence for right-handed currents is found in the charged-current neutrino scattering data. The masses of produced heavy quarks are estimated. (AIP)
110 citations
CERN1
TL;DR: In this article, the authors study subasymptotic hadron target and quark-parton mass corrections to scaling in deep inelastic scattering, ignoring interactions, using a modified scaling variable common to parton, light-cone and short-distance operator product expansion formalisms, with model-dependent spectral conditions.
102 citations
TL;DR: In this paper, the meson sector of two-dimensional quantum chromodynamics has been clarified and the complete completeness of 't Hooft's solution has been shown for mesons.
Abstract: We clarify the gauge invariance, infrared structure, and completeness of 't Hooft's solution for the meson sector of two-dimensional quantum chromodynamics. Electromagnetic form factors of mesons are then shown to obey an asymptotic power law, whose power is dynamically determined and is not related to the short-distance behavior of the theory. Following a review of the total annihilation cross section for producing hadrons, we discuss deep-inelastic lepton scattering. As expected, Bjorken scaling is obtained, but we show how the sum over hadronic final states reproduces the parton model precisely. The Drell-Yan-West relation and Bloom-Gilman duality are fulfilled for the relation between the scaling function and form factors. We conclude by speculating on the applicability of our picture of form factors to the real, four-dimensional world. We argue that this is a viable alternative to dimensional scaling and, phenomenologically, the differences between our predictions and the dimensional counting rules are slight for light quarks. Finally, we attempt to abstract those features of the model which may guide us toward a solution to the four-dimensional problem. (AIP)
102 citations
CERN1
TL;DR: In this paper, the authors study quark-parton and hadron target mass corrections to Bjorken scaling using the parton model, the lightcone expansion, and operator product expansion techniques motivated by asymptotic freedom.
50 citations
TL;DR: In this paper, it was shown that the space-time evolution of hadron final states in deep inelastic processes can be made consistent with the hypotheses of the parton model (and therefore also with the trends of the data at present) provided that there exist long-range rapidity correlations in the deep-inelastic dynamics.
Abstract: In summary, we have found that the picture of space-time evolution of hadron final states in deep inelastic processes isn't totally trivial, and also have found that it can be made consistent with the hypotheses of the parton model (and therefore also with the trends of the data at present). This is only the case provided that there exist long-range rapidity correlations in the deep inelastic dynamics. This is in fact what is indicated in two dimensional quantum electrodynamics, as discovered by Casher, Kogut and Susskind. It strongly suggests the relevance of some kind of gauge theory as a necessary element in the interpretation of the confinement problem. Finally it is clear that the discussion above is so qualitative that while hopefully providing some insight into the space-time geography of what is going on, it is a far cry from what we should like to have in order to make quantitative comparisons with experiment. In fact, I see the above description as a solution to a problem which hasn't been well defined. The problem remaining is to try to sharpen the above considerations by specifying precisely what the problem is that is to be solved. Perhaps it is a variant of the Landau hydrodynamic model, but one which incorporates the concepts of short range correlation in rapidity instead of Landau's concept of total arrest of hadronic matter in hadron-hadron collisions. If such a hydrodynamic picture could be worked out it might lead to some further insights into the dynamics of confinement and of deep inelastic processes.
42 citations
TL;DR: In this paper, a simple model field theory is applied to μ-pair production and it is shown that the transverse momentum distribution will spread at moderate values of √Q2, the mass of the µ-pair, but its rate of growth will become negligible at high Q2 as the theory's invariant charge vanishes.
42 citations
TL;DR: In this article, the production of heavy quarks is considered in the quarkparton model and the model is shown to account for the energy-dependent effects of large produced masses.
Abstract: The production of heavy quarks is considered in the quark-parton model. The model is shown to account for the energy-dependent effects of large produced masses. By considering the inclusive, charged-current neutrino scattering data as a function of energy, it is possible to distinguish between the standard four-quark model and models with right-handed currents and additional heavy quarks. It appears that the present data favor the latter models, and allow estimates of the masses of new quarks.
38 citations
TL;DR: In this paper, the authors estimate renormalization effects on σν /σν and 〈y〉ν in the standard four-quark model, improving on a calculation by Altarelli, Petronzio, and Parisi.
Abstract: We estimate renormalization effects on σν / σν and 〈y〉ν in the standard four-quark model, improving on a calculation by Altarelli, Petronzio, and Parisi. Even with systematic overestimates, the Weinberg-Salam model does not give a satisfactory account of the data.
37 citations
TL;DR: In this paper, the authors consider the problem of mass dependent corrections to scaling in the covariant parton model and indicate the type of mass dependence which a complete theory must reproduce in the limit of weak coupling.
33 citations
TL;DR: In this article, a detailed parton model for dileptons originating in the production and decay of "charmed" particles in high-energy neutrino interactions was constructed, and distributions were calculated for the primary and secondary lepton, and for the hadronic shower accompanying them.
TL;DR: In this article, the authors considered the process e/sup +/e/sup -/..-->....gamma.. + h + X, where h is a hadron and π is a hard photon, and show how it can be used to test the quarkparton model.
Abstract: We consider the process e/sup +/e/sup -/ ..-->.. ..gamma.. + h + X, where h is a hadron and ..gamma.. is a hard photon, and show how it can be used to test the quark-parton model. Detailed formulas are given for the cross sections, which in the quark-parton model are products of cross sections for e/sup +/e/sup -/ ..-->.. ..gamma mu..anti ..mu.. and quark breakup functions. We focus on the asymmetry between h and h-bar production, and display sum rules and ratio tests which measure the quark charge, the quark Compton amplitude, and the large-x behavior of the quark breakup function. The asymmetry is calculated for the muon case, and is about 100% for the forward direction. (AIP)
TL;DR: In this article, the dispersion approach to the deuteron is developed which is in the straight forward correspondence both with quantum mechanics and the parton model, and the deep inelastic eD struction function in the region forbidden for scattering from free nucleon is calculated in agreement with the recent Stanford experiment.
TL;DR: A neutrino-proton scattering experiment has been performed at Fermilab by using a wide-band horn-focused NE beam and the 15-ft bubble chamber filled with hydrogen as mentioned in this paper.
Abstract: A neutrino--proton scattering experiment has been performed at Fermilab by using a wide-band horn-focused neutrino beam and the 15-ft bubble chamber filled with hydrogen. For the inclusive reaction $nu$/sub $mu$/ + p $Yields$ $mu$$sup -$ + hadrons, the mean value of Q$sup 2$ is found to increase linearly with energy, as is expected from Bjorken scaling, and a fit to the data gives = (0.18 +- 0.01) E. The distribution in the Bjorken scaling variable x shows evidence for deviations from predictions based on electron-scattering data and the quark-parton model. (AIP)
TL;DR: In this paper, color effects in unified gauge theories with lepton probes are discussed and quantitatively discussed at energies higher than 50 GeV, and several new results pertaining to these effects are derived.
Abstract: In unified gauge theories with color (excitable by lepton probes), color effects become manifest in the asymptotic region through gluon terms. Several new results pertaining to these are derived and quantitatively discussed. These may be testable at energies higher than 50 GeV now available.
TL;DR: In this paper, the influence of the size of the target nucleus on the energy of a proton-nucleus collision was analyzed with respect to the number of nucleons in the path of the incoming proton.
TL;DR: In this paper, generalized vector meson dominance is used as a method for inserting mass effects into the simple quark parton model, and the implementation of quark model symmetries implies relations among the towers of vector resonances, which specify the magnitude and approach to scaling of different qq sea components in deep inelastic electron and neutrino scattering.
CERN1
TL;DR: In this paper, the authors treat massive electrodynamics as a model for the production of massive μ pairs in high-energy hadronic collisions and identify the dominant diagrams in perturbation theory.
TL;DR: In this paper, generalized vector meson dominance (GVMD) is used to extend parton model results away from the strict Bjorken scaling limit into regions where mass scales play an important role.
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TL;DR: In this paper, a simple parton model is generalized to incorporate the renormalization group approach of scale invariance at short distances, and a few outstanding problems in the quark-parton model are mentioned.
Abstract: Beginning with a short review of kinematics for the electron, muon, and neutrino scattering and the recent experimental status of Bjorken scaling, the formulation of the parton model is developed for electron and neutrino scattering. Basic ideas and assumptions of the model are discussed. The model is then applied to the inclusive one-hadron spectrum in the final states of electron scattering, electron--positron annihilation into hadrons, and massive lepton pair production in proton--proton collisions. The simple parton model is generalized to incorporate the renormalization group approach of scale invariance at short distances. Finally, a few outstanding problems in the quark--parton model are mentioned. 105 references. (JFP)
TL;DR: In this article, the production and decay of a massive charmed particle is examined in a parton model which has been modified to realistically incorporate the threshold due to the large mass of the charmed particles, and the model predicts threshold scaling violations which are unexpectedly large and persist out to several hundred GeV in neutrino energy.
TL;DR: In this article, a quark·gluon-parton model is presented in which quark-partons and gluons are making clusters as corresponding to two or three constituent quarks (or anti-quarks) in the meson or in the baryon, respectively.
Abstract: We present a quark·gluon-parton model in which quark-partons and gluons are making clusters as corresponding to two or three constituent quarks (or anti-quarks) in the meson or in the baryon, respectively. We explicitly construct the constituent quark state (cluster), by employing the Kuti-Weisskopf theory and by requiring the scaling. The quark additivity of the hadronic total cross sections and the quark counting rules on the threshold powers of various distributions are satisfied. For small x (Feynman fraction), it is shown that the constituent quarks and quark-partons have quite different probability distributions. We apply our model to hadron-hadron inclusive reactions, and clarify that the fragmentation and the diffractive processes relate to the constituent quark distributions, while the processes in or near the central region are controlled by the quark-partons. Our model gives the reasonable interpretation for the experimental data and much improv:cs the usual "constituent inter change model" result near and in the central region (x=xr=O).
TL;DR: In this paper, the neutrino quark distributions were determined from new Fermilab νN and ḡnN deep inelastic scattering data, with E x distributions so determined also agree with the 30 E E > 80 GeV data, so there is no evidence for a breakdown of scaling or new mechanisms in d σ /d x.
TL;DR: In this article, a covariant parton model formulation of deep inelastic processes is investigated and it is shown that a consistent theory requires that the convergence properties of parton-hadron amplitudes should be modified as well as the partons being given form factors.
TL;DR: In this article, the Drell-Yan contribution to the massive lepton-pair production in hadron-hadron scattering is calculated using the parton distributions extracted from deep inelastic eN and νN scattering data.
TL;DR: In this paper, the Drell-Yan process of heavy lepton pair production in hadronic collisions is discussed in a parton model which gives logarithmic corrections to Bjorken scaling.
TL;DR: In this paper, a modification of the quark-fusion model for large p T meson production is proposed, which results in a suppression of an expected leading particle mechanism, and leads to single-particle cross sections comparable to those from a proton beam.