About three decades after the first experiments on deep inelastic lepton hadron scattering began to investigate the structure of hadrons, the history of this fruitful field of particle physics continues in the broad spectrum of research performed at the electron and positron proton collider HERA at DESY, where the multipurpose detectors ZEUS and H1 access ep scattering at a center of mass energy of 300 GeV and explore as yet uncharted kinematic realms of deep inelastic scattering. After the first years of data taking at HERA, each of the experiments has collected a total of roughly 40 pb 1 of e+p data, yielding sensitivity to deep inelastic e+p interactions at high four momentum transfers, Q2, where typi cal cross sections drop into the subpicobarn regime. This kinematic domain is characterized by electroweak unification, manifesting itself most markedly in the neutral and charged current cross sections, which approach an equal order of magnitude as Q2 rises above the square of the W and Z masses. Consequently, HERA allows, for the first time, studies of both types of pro cesses simultaneously with the same initial state conditions and in the same detector, and thus we can investigate the interplay of electroweak and strong forces governing the respective cross sections.

The production of heavy quarks in high-energy experiments offers a rich field to study, both experimentally and theoretically. Due to the additional quark mass, the description of these processes in the framework of perturbative QCD is much more demanding than it is for those involving only massless partons. In the last two decades, a large amount of precision data has been collected by the deep inelastic HERA experiment. In order to make full use of these data, a more precise theoretical description of charm quark production in deep inelastic scattering is needed. This work deals with the first calculation of fixed moments of the NNLO heavy flavor corrections to the proton structure function F2 in the limit of a small charm-quark mass. The correct treatment of these terms will allow not only a more precise analysis of the HERA data, but starting from there also a more precise determination of the parton distribution functions and the strong coupling constant, which is an essential input for LHC physics. The complexity of this calculation requires the application and development of technical and mathematical methods, which are also explained here in detail.

This workshop is the fourth of a series initiated in Durham (March 93), followed by Eilat (February 94) and Paris (April 95). The large interest and the great inflow of experimental data, coming mainly from HERA, are some of the reasons behind the decision to have this annual meeting, presently the most important one for this area of research. During the workshop, experimental results and theoretical aspects have been reported on subjects, which have been organised by working groups on: 1) hadron structure functions; 2) photoproduction and photon structure; 3) diffractive interactions; 4) hadronic final states; 5) spin effects in lepton nucleon scattering; 6) special session on theoretical advances. While the contributions to the working groups offer hot material for specialists, the reports by the conveners, as well as other contributions to the plenary sessions, offer to nonspecialists a complete overview of this research field.

This graduate/research level book describes our present knowledge of protons and neutrons, the particles which make up the nucleus of the atom. Experiments using high energy electrons, muons and neutrinos reveal the proton as being made up of point-like constituents, quarks. The strong forces which bind the quarks together are described in terms of the modern theory of quantum chromodynamics (QCD), the â€~glue' binding the quarks being mediated by new constituents called gluons. Larger and new particle accelerators probe the interactions between quarks and gluons at shorter distances. The understanding of this detailed substructure and of the fundamental forces responsible is one of the keys to unravelling the physics of the structure of matter. This book will be of interest to all theoretical and experimental particle physicists.

This book provides an up-to-date, self-contained account of deep inelastic scattering in high-energy physics, intended for graduate students and physicists new to the subject. It covers the classic results which led to the quark-parton model of hadrons and the establishment of quantum chromodynamics as the theory of the strong nuclear force, in addition to new vistas in the subject opened up by the electron-proton collider HERA. The extraction of parton momentum distribution functions, a key input for physics at hadron colliders such as the Tevatron at Fermi Lab and the Large Hadron Collider at CERN, is described in detail. The challenges of the HERA data at 'low x' are described and possible explanations in terms of gluon dynamics and other models outlined. Other chapters cover: jet production at large momentum transfer and the determination of the strong coupling constant, electroweak interactions at very high momentum transfers, the extension of deep inelastic techniques to include hadronic probes, a summary of fully polarised inelastic scattering and the spin structure of the nucleon, and finally a brief account of methods in searching for signals 'beyond the standard model'.

These proceedings present the most up-to-date status of deep inelastic scattering (DIS) physics. Topics such as structure function measurements and phenomenology, quantum chromodynamics (QCD) studies in DIS and photoproduction, spin physics and diffractive interactions are reviewed in detail, with emphasis on those studies that push the test of QCD and the Standard Model to the limits of their present range of validity, towards both the very high and the very low four-momentum transfers in leptonproton scattering.

Small-x Behavior of Deep Inelastic Structure Functions in QCD covers the proceedings of the DESY topical meeting entitled ""Small-x Behavior of Deep Inelastic Structure Functions in QCD"", held in DESY, Hamburg, Germany on May 14-16, 1990. The book focuses on Quantum Chromo Dynamics (QCD) structure function technology, including structure function measurements, photon structure, multi-parton interactions, and hadronic collisions. The selection first offers information on structure function measurements at Hera and pomeron and odderon in QCD and a two-dimensional conformal field theory. Topics include nucleon structure function measurements, handles on the gluon distribution, and photon structure. The book also examines Regge poles in asymptotic free theories; QCD phenomenology of parton distribution functions at small x; and possible parametrization of parton distributions. The text elaborates on low x structure function and saturation of the parton density and photon diffractive dissociation in deep inelastic scattering. The publication also considers multi-parton interactions in high energy hadronic collisions and bound-state quark and gluon contributions to structure functions in QCD. Discussions focus on bound valence-quark distributions, intrinsic gluon distribution of protons, and intrinsic charm-quark distributions. The selection is a dependable reference for readers interested in small-x behavior of deep inelastic structure functions in QCD.