A QCD Analysis of Structure Function Data from Electron Proton Collisions in the H1 Experiment
Author: Athanasios Mavroidis
Publisher:
Published: 1995
Total Pages:
ISBN-13:
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QCD at HERA
Author: Michael Kuhlen
Publisher: Springer
Published: 1999
Total Pages: 202
ISBN-13:
DOWNLOAD EBOOKThe book provides a review of the hadronic final state measurements at HERA in deep inelastic scattering. It covers general event properties, particle spectra, heavy flavours, jets, event shape measurements, QCD instantons and small-x physics. The emphasis is on experimental results, providing quick access to the data (complete up to fall 1997) for reference. The results are discussed in the context of QCD.
QCD Radiation in Top-Antitop and Z+Jets Final States
Author: Kiran Joshi
Publisher: Springer
Published: 2015-06-12
Total Pages: 188
ISBN-13: 3319196537
DOWNLOAD EBOOKThis thesis contains new research in both experimental and theoretical particle physics, making important contributions in each. Two analyses of collision data from the ATLAS experiment at the LHC are presented, as well as two phenomenological studies of heavy coloured resonances that could be produced at the LHC. The first data analysis was the measurement of top quark-antiquark production with a veto on additional jet activity. As the first detector-corrected measurement of jet activity in top-antitop events it played an important role in constraining the theoretical modelling, and ultimately reduced these uncertainties for ATLAS's other top-quark measurements by a factor of two. The second data analysis was the measurement of Z+2jet production and the observation of the electroweak vector boson fusion (VBF) component. As the first observation of VBF at a hadron collider, this measurement demonstrated new techniques to reliably extract VBF processes and paved the way for future VBF Higgs measurements. The first phenomenological study developed a new technique for identifying the colour of heavy resonances produced in proton-proton collisions. As a by-product of this study an unexpected and previously unnoticed correlation was discovered between the probability of correctly identifying a high-energy top and the colour structure of the event it was produced in. The second phenomenological study explored this relationship in more detail, and could have important consequences for the identification of new particles that decay to top quarks.
Deep Inelastic Positron-Proton Scattering in the High-Momentum-Transfer Regime of HERA
Author: Ulrich F. Katz
Publisher: Springer
Published: 2003-07-01
Total Pages: 243
ISBN-13: 354045019X
DOWNLOAD EBOOKAbout 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.
A Measurement of the Proton Structure Function and a First Determination of the Gluon Distribution at Hera
Author: Maria Teresa P. Roco
Publisher:
Published: 1994
Total Pages: 350
ISBN-13:
DOWNLOAD EBOOKAssociated Production of W + Charm in 13 TeV Proton-Proton Collisions Measured with CMS and Determination of the Strange Quark Content of the Proton
Author: Svenja Karen Pflitsch
Publisher: Springer Nature
Published: 2020-08-18
Total Pages: 156
ISBN-13: 303052762X
DOWNLOAD EBOOKThe associated production of a W boson and a single charm quark (W+c) is the only process in proton-proton collisions that directly probes the strange quark content of the proton. In this thesis, W+charm production is measured in proton-proton collisions at the LHC at 13 TeV, as recorded by the Compact Muon Solenoid (CMS) experiment. The analysis focuses on the identification of W bosons in their leptonic decay to a muon and a neutrino and charm quarks are tagged via the full reconstruction of D*-Mesons. The measured cross sections of W+c production are used, in combination with other relevant CMS results and the most precise HERA DIS data, in a QCD analysis to determine the strange quark content of the proton. The resulting strange quark distribution and suppression, with respect to the other light sea quarks, are in good agreement with those obtained in neutrino scattering experiments and extend their kinematic reach.
The Quark Structure of Hadrons
Author: Claude Amsler
Publisher: Springer
Published: 2018-10-30
Total Pages: 276
ISBN-13: 3319985272
DOWNLOAD EBOOKNovel 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
Author: Steven D. Bass
Publisher: World Scientific
Published: 2008
Total Pages: 212
ISBN-13: 9812709487
DOWNLOAD EBOOKOne 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 OCo 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. Sample Chapter(s). Chapter 1: Introduction (159 KB). Contents: Spin Experiments and Data; Dispersion Relations and Spin Sum Rules; g 1 Spin Sum Rules; Fixed Poles; The Axial Anomaly, Gluon topology and g (0) A; Chiral Symmetry and Axial U(1) Dynamics; QCD Inspired Models of the Proton Spin Problem; The Spin-Flavour Structure of the Proton; QCD Fits to g 1 Data; Polarized Quark Distributions; Polarized Glue o g(x, Q 2 ); Transversity; Deeply Virtual Compton Scattering and Exclusive Processes; Polarized Photon Structure Functions; Conclusions and Open Questions: How Does the Proton Spin?. Readership: Academics, as well as physicists working on particle and nuclear physics at the interface of theory and experiment.
Proceedings of the Ringberg Workshop New Trends in HERA Physics 2005
Author: Gnter Grindhammer
Publisher: World Scientific
Published: 2006
Total Pages: 405
ISBN-13: 9812773525
DOWNLOAD EBOOKThe purpose of this volume is to gather the latest experimental results from the H1, ZEUS and HERMES collaborations and to capture new trends in HERA phenomenology. The presentations are by experts for experts, but are suitable for a mixed readership of both theoreticians and experimentalists. H1 members also cover ZEUS results and vice versa. This is the place where discrepancies between experimental data and theoretical predictions are pointed out and ventilated and where projects to be launched in the future are identified. Contents: Electroweak Physics at HERA (J Meyer); Resummed Perturbative Evolution at High Energy (R Ball); Measurements of s and Parton Distribution Functions Using HERA Jet Data (A Cooper-Sakar); A New Parton Shower Algorithm: Shower Evolution, Matching at Leading and Next-to-Leading Order Level (Z Nagy); J/ e Photoproduction at Large z in Soft Collinear Effective Theory (S Fleming); New Resonances in the Hadronic Final State at HERA (K Tokushuku); Hadron Systematics and Emergent Diquarks (F Wilczek); Importance of a Measurement of F L (X, Q 2 ) at HERA (R Thorne); Measurement of the Longitudinal Proton Structure Function at Low x at HERA (J Feltesse); HERA and the LHC (A De Roeck); and other papers. Readership: Graduate students, academics and researchers in accelerator and particle physics."
Proton Structure
Author: William L. Stubbs
Publisher: CreateSpace
Published: 2015-03-12
Total Pages: 106
ISBN-13: 9781508664062
DOWNLOAD EBOOKBeta 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.
