Deep Inelastic Positron-Proton Scattering in the High-Momentum-Transfer Regime of HERA

Deep Inelastic Positron-Proton Scattering in the High-Momentum-Transfer Regime of HERA
Author: Ulrich F. Katz
Publisher: Springer
Total Pages: 243
Release: 2003-07-01
Genre: Science
ISBN: 354045019X

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.

Proton Structure

Proton Structure
Author: William L. Stubbs
Publisher: CreateSpace
Total Pages: 106
Release: 2015-03-12
Genre:
ISBN: 9781508664062

Beta decay implies that electrons and positrons reside within the nucleus of the atom. However, despite countless observations of electrons and positrons leaving the nucleus, the discovery of the neutron put an end to that notion. Proton Structure examines data collected on the proton over 50 years, to determine what a proton looks like. The book discusses the techniques used to interpret the data, in a manner many can understand. It walks, step-by-step, through the data collected, explaining what each aspect of the data reveals, to make a strong case for protons (and neutrons) made of electrons and positrons. Finally, it briefly looks at some implications of having nucleons made of these particles. Proton Structure takes another look at the structural data gathered on the proton, and offers a model of the proton that fits nicely into the world we see around us.

Hadron Structure in Electroweak Precision Measurements

Hadron Structure in Electroweak Precision Measurements
Author: Nathan L. Hall
Publisher: Springer
Total Pages: 127
Release: 2015-07-24
Genre: Science
ISBN: 3319202219

This thesis examines the γZ box contribution to the weak charge of the proton. Here, by combining recent parity-violating electron-deuteron scattering data with our current understanding of parton distribution functions, the author shows that one can limit this model dependence. The resulting construction is a robust model of the γγ and γZ structure functions that can also be used to study a variety of low-energy phenomena. Two such cases are discussed in this work, namely, the nucleon’s electromagnetic polarizabilities and quark-hadron duality. By using phenomenological information to constrain the input structure functions, this important but previously poorly understood radiative correction is determined at the kinematics of the parity-violating experiment, QWEAK, to a degree of precision more than twice that of the previous best estimate. A detailed investigation into available parametrizations of the electromagnetic and interference cross-sections indicates that earlier analyses suffered from the inability to correctly quantify their model dependence.

Hadron Collider Physics 2002

Hadron Collider Physics 2002
Author: Martin Erdmann
Publisher: Springer Science & Business Media
Total Pages: 572
Release: 2003
Genre: Science
ISBN: 9783540009955

I Opening Review on Hadron-Collider Physics.- Hadron Colliders, the Standard Model, and Beyond.- 1 What is the Standard Model?.- 2 Hadron Colliders and the Standard Model.- 2.1 Precision electroweak.- 2.2 CKM.- 2.3 Top quark.- 2.4 Higgs boson.- 2.5 QCD.- 3 Beyond the Standard Model.- 3.1 Direct evidence.- 3.2 Indirect evidence.- References.- II Status of the Accelerators and Detectors.- Tevatron Collider Run II Status.- 1 Introduction.- 2 Overview.- 3 Run II Milestones.- 4 Parameters.- 5 Performance to Date.- 6 Accomplishments.- 6.1 Accomplishments: Helix Adjustments.- 6.2 Accomplishments: Antiproton Emittance.- 6.3 Accomplishments: Tevatron Injection Closure.- 7 Outstanding Issues.- 8 Future Prospects.- 9 Reliability.- 10 Summary.- 11 Acknowledgements.- Status of CDF II and Prospects for Run II.- 1 Introduction.- 2 The CDF II Detector and Trigger Upgrades.- 3 Physics Results and Prospects.- 4 Conclusions.- References.- Status of the D Detector.- 1 Introduction.- 2 Overview.- 3 Silicon Vertex Detector.- 4 Central Fiber Tracker.- 5 Calorimeters.- 6 Muon Detectors.- 7 Forward Proton Detectors.- 8 Trigger and Data Acquisition.- 9 Conclusions.- References.- III Standard Model Processes: Parton Luminosities, QCD Evolution.- The Proton Structure as Measured at HERA.- 1 Introduction.- 2 NC Cross Sections in the Complete Kinematic Plane.- 3 High-Q2 Measurements.- 4 Charged Current Measurements.- 5 Summary and Outlook.- References.- Global Fits of Parton Distributions.- 1 Introduction.- 2 Parton Uncertainties.- 2.1 Hessian (Error Matrix) approach.- 2.2 Offset method.- 2.3 Statistical approach.- 2.4 Lagrange multiplier method.- 2.5 Results.- 3 Theoretical Errors.- 3.1 Problems in the fit.- 3.2 Types of Theoretical Error, NNLO.- 3.3 Empirical approach.- 4 Conclusions.- References.- Low x Physics at HERA.- 1 Introduction.- 2 Formalism and Theory.- 3 Results.- 3.1 Inclusive measurements.- 3.2 Exclusive results.- 4 Summary.- References.- Saturation Effects in Hadronic Cross Sections.- 1 Introduction.- 2 The Loop-Loop Correlation Model.- 3 Saturation in Proton-Proton Scattering.- 4 Gluon Saturation.- 5 Conclusion.- References.- IV Standard Model Processes: QCD at High pt.- Progress in NNLO Calculations for Scattering Processes.- 1 Why NNLO Calculations are Important.- 1.1 Renormalisation scale uncertainty.- 1.2 Factorisation scale dependence.- 1.3 Jet algorithms.- 1.4 Transverse momentum of the incoming partons.- 1.5 Power corrections.- 1.6 The shape of the prediction.- 1.7 Parton densities at NNLO.- 2 Recent Progress in the Field.- 3 What Remains to be Done.- References.- Heavy Flavour Production at D .- 1 Introduction.- 2 b-production Cross-section.- 2.1 Muon and Jet Cross-section.- 2.2 b-tagging.- 3 J/? Cross-section.- 4 Other Measurements.- References.- Heavy Quark Production at CDF.- 1 Introduction.- 2 Beauty Production at CDF.- 2.1 CDF Run I results.- 2.2 Preliminary results from CDF Run II.- 3 Quarkonia Production at CDF.- 4 Charm Production at CDF.- 4.1 Run I results.- 4.2 Run II charm production cross-sections.- 5 Conclusion.- References.- Heavy Quark Production at HERA.- 1 Introduction.- 2 Open Charm Production.- 3 Charmonium.- 4 Beauty Production.- 5 Summary.- References.- Theoretical Developments on Hard QCD Processes at Colliders.- 1 Introduction.- 2 Heavy Quarks.- 2.1 Total Cross Sections.- 2.2 Transverse Momentum Distributions.- 2.3 Top Quark Spin Correlations.- 3 Jets.- 3.1 Jet Definitions.- 3.2 Precision Jet Physics.- 3.3 Multiparton Processes.- 4 Photons and Massive Gauge Bosons.- 4.1 Isolated Photons.- 4.2 Photon Pairs.- 4.3 Vector Boson and Higgs Production.- 4.4 Transverse Momentum Distributions.- 5 Conclusions and Outlook.- References.- Jet Production at CDF.- 1 Introduction.- 2 Inclusive Jet Production.- 3 Three-jet Production.- 4 Study of Jet Shapes in Run 2.- 5 Study of the Underlying Event.- 6 Study of W+Njet Production.- References.- Jet Algorithms at D .- 1 Introduction.- 2 The Measurement of Jets.- 3 Run I Co

Exclusive Production of Neutral Vector Mesons at the Electron-Proton Collider HERA

Exclusive Production of Neutral Vector Mesons at the Electron-Proton Collider HERA
Author: James A. Crittenden
Publisher: Springer
Total Pages: 122
Release: 1997-10-06
Genre: Science
ISBN:

The first five years of operation of the two multi-purpose experiments ZEUS and H1 at the HERA electron--proton storage ring facility in Hamburg, Germany have opened a new era in the study of diffractive vector-meson production in high-energy photon--proton interactions. This book provides readers who have a general knowledge of the concepts and experimental techniques of elementary particle physics with the information necessary to assess the status of the new investigations prior to the end of 1996. The measurements are placed in the rich historical context of earlier studies of photo- and leptoproduction of vector mesons.

Current Hadron Interactions

Current Hadron Interactions
Author: J. Thanh Van Tran
Publisher: Atlantica Séguier Frontières
Total Pages: 722
Release: 1979
Genre: Hadron interactions
ISBN: 9782863320051

The Quark Structure of Hadrons

The Quark Structure of Hadrons
Author: Claude Amsler
Publisher: Springer
Total Pages: 276
Release: 2018-10-30
Genre: Science
ISBN: 3319985272

Novel forms of matter, such as states made of gluons (glueballs), multiquark mesons or baryons and hybrid mesons are predicted by low energy QCD, for which several candidates have recently been identified. Searching for such exotic states of matter and studying their production and decay properties in detail has become a flourishing field at the experimental facilities now available or being built - e.g. BESIII in Beijing, BELLE II at SuperKEKB, GlueX at Jefferson Lab, PANDA at FAIR, J-PARC and in the upgraded LHC experiments, in particular LHCb. A modern primer in the field is required so as to both revive and update the teaching of a new generation of researchers in the field of QCD. These lectures on hadron spectroscopy are intended for Master and PhD students and have been originally developed for a course delivered at the Stefan Meyer Institute of the Austrian Academy of Sciences. They are phenomenologically oriented and intended as complementary material for basic courses in particle and nuclear physics. The book describes the spectra of light and heavy mesons and baryons, and introduces the fundamental properties based on symmetries. Further, it derives multiplet structures, mixing angle, decay coupling constants, magnetic moments of baryons, and predictions for multiquark states and compares these with suitable experimental data. Basic methods of calculating decay angular distributions and determining masses and widths of resonances are also presented. The appendices provide students and newcomers to the field with the necessary background information, and include a set of problems and solutions.

The Spin Structure of the Proton

The Spin Structure of the Proton
Author: Steven D. Bass
Publisher: World Scientific
Total Pages: 212
Release: 2008
Genre: Science
ISBN: 9812709460

One of the main challenges in nuclear and particle physics in the last 20 years has been to understand how the proton's spin is built up from its quark and gluon constituents. Quark models generally predict that about 60% of the proton's spin should be carried by the spin of the quarks inside, whereas high energy scattering experiments have shown that the quark spin contribution is small - only about 30%. This result has been the underlying motivation for about 1000 theoretical papers and a global program of dedicated spin experiments at BNL, CERN, DESY and Jefferson Laboratory to map the individual quark and gluon angular momentum contributions to the proton's spin, which are now yielding exciting results. This book gives an overview of the present status of the field: what is new in the data and what can be expected in the next few years. The emphasis is on the main physical ideas and the interpretation of spin data. The interface between QCD spin physics and the famous axial U(1) problem of QCD (eta and etaprime meson physics) is also highlighted. Book jacket.