Download or read book Twist 3 Spin Observables for Single hadron Production in DIS written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Recently, three twist-3 spin asymmetries for single-inclusive hadron production in deep-inelastic lepton-nucleon scattering have been computed using collinear factorization and the leading order approximation. Here we summarize the main findings of these studies.
Download or read book Testing QCD Through Spin Observables in Nuclear Targets written by Don G. Crabb and published by World Scientific. This book was released on 2003 with total page 338 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains the invited talks and contributed papers presented at the workshop on ?Testing QCD Through Spin Observables in Nuclear Targets?, held at the University of Virginia in April 2002.The workshop was proposed in the context of the large number of experiments that have used polarized deuterons or polarized 3He to extract information about the spin parameters of the neutron. The motivation for this workshop was to study the effects of the nuclear medium on the spin properties of the bound nucleon and to explore issues in QCD that might be resolved through spin observables in nuclear targets: What is the effect of the nuclear medium on the measured asymmetries? How have the latest results on the spin structure of the nucleon and the nucleon form factors changed our thinking? What advances are anticipated in the development of polarized targets?
Download or read book Transverse Spin Observables in Hadron hadron and Hadron nucleus Collisions written by and published by . This book was released on 1991 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: Transverse, single-spin asymmetries offer a chance to test QCD at the level of twist-3'' observables. Early suggestions that such asymmetries necessarily vanish as m{sub q} → 0 or involve an extra power of [alpha]{sub s} can be refuted with a simple example. Recent experimental results support the interpretation of these data in hard-scattering QCD. The asymmetry in the scattering on nuclear targets can provide new, nontrivial information the space-time structure of the interaction. 10 refs., 6 figs.
Download or read book Spin 96 Proceedings Of The 12th International Symposium On High energy Spin Physics written by J E J Oberski and published by World Scientific. This book was released on 1997-04-15 with total page 906 pages. Available in PDF, EPUB and Kindle. Book excerpt: Experiments using highly polarized intense beams and targets, and theoretical studies of spin and polarization phenomena, are now providing us with numerous additional details of the electroweak and strong interactions and the structure of matter. The spin structure of the nucleon has been measured over wide ranges of kinematic variables, and the cross sections have been calculated to several orders in perturbative field theory. At present, the influence of the higher twist contributions, the gluon spin, and the quark orbital angular momentum are under scrutiny. Quantum chromodynamics (QCD) captures a lot of our experimental knowledge of hard polarized scattering processes. Can our understanding of such processes within QCD be further improved?Hyperons produced in high energy reactions show how puzzling strong interactions between hadrons still are. Spin observables in experiments at intermediate energy are used to test parity and charge symmetries. Will they also reveal, at low energy, a violation of time reversal symmetry? We are on the verge of using parity violation measurements at intermediate electron scattering energies to determine the amount of strange quark contributions to the neutral weak form factor of the nucleon. The polarization of the sea quarks is expected to be measured soon in W± decays produced in high energy polarized proton interactions. Will the jets in polarized Z⁰ decays show a definite handedness? These and many other topics are discussed in these proceedings.
Download or read book Three dimensional Partonic Structure of the Nucleon written by Mauro Anselmino and published by IOS Press. This book was released on 2012 with total page 392 pages. Available in PDF, EPUB and Kindle. Book excerpt: The three-dimensional nucleon structure is central to many theoretical and experimental activities, and research in this field has seen many advances in the last two decades, addressing fundamental questions such as the orbital motion of quarks and gluons inside the nucleons, their spatial distribution, and the correlation between spin and intrinsic motion. A real three-dimensional imaging of the nucleon as a composite object, both in momentum and coordinate space, is slowly emerging.This book presents lectures and seminars from the Enrico Fermi School Three-Dimensional Partonic Structure of the Nucleon, held in Varenna,
Download or read book Transverse Spin Physics written by Vincenzo Barone and published by World Scientific. This book was released on 2003-01-29 with total page 308 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is devoted to the theory and phenomenology of transverse-spin effects in high-energy hadronic physics. Contrary to common past belief, it is now rather clear that such effects are far from irrelevant. A decade or so of intense theoretical work has shed much light on the subject and brought to surface an entire class of new phenomena, which now await thorough experimental investigation. Over the next few years a number of experiments world-wide (at BNL, CERN, DESY and JLAB) will run with transversely polarised beams and targets, providing data that will enrich our knowledge of the transverse-spin structure of hadrons. It is therefore timely to assess the state of the art, and this is the principal aim of the volume.An outline of the book is as follows. After a few introductory remarks (Chapter 1), attention is directed in Chapter 2 to transversely polarised deeply-inelastic scattering (DIS), which probes the transverse spin structure function g2. This existing data are reviewed and discussed (for completeness, a brief presentation of longitudinally polarised DIS is also provided). In Chapter 3 the transverse-spin structure of the proton is illustrated in detail, with emphasis on the transversity distribution and the twist-three parton distribution contributing to g2. Model calculations of these quantities are also presented. In Chapter 4, the QCD evolution of transversity is studied at leading and next-to-leading order. Chapter 5 illustrates the g2 structure function and its related sum rules within the framework of perturbative QCD. The last three chapters are devoted to the phenomenology of transversity, in the context of Drell-Yan processes (Chapter 6), inclusive leptoproduction (Chapter 7) and inclusive hadroproduction (Chapter 8). The interpretation of some recent single-spin asymmetry data is discussed and the prospects for future measurements are reviewed.
Download or read book DIS 99 written by Johannes Blümlein and published by . This book was released on 1999 with total page 828 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Transversity 2008 written by Ciullo Giuseppe and published by World Scientific. This book was released on 2009 with total page 313 pages. Available in PDF, EPUB and Kindle. Book excerpt: Transversity 2008, the second workshop on OC Transverse polarization phenomena in hard processesOCO follows the first one held in Como after three years. As in that case, the event comes at the end of a two-years project financed by the Italian Ministry of Education. In the time between the two Workshops, decisive steps towards the revealing of the transverse spin structure of the proton were taken on both the theoretical and experimental sides. The milestone of the first extraction of Transversity and the Sivers function for the u- and d-quarks deserves a special mention. In the same period, historic experiments that in the last decade contributed to the first pioneering measurements in the SIDIS sector, have concluded their data taking, and their place is being taken by upgrades of existing or new facilities. These are the result of the new interesting phenomena which are appearing and call for additional experimental information and novel experimental techniques. Over 80 physicists took part in the Workshop. Equally involved were experimentalists and theoreticians engaged in investigating the nature of transverse spin. The heterogeneous public favoured vivid discussions and fruitful exchange of up-to-date theoretical and experimental ideas on this constantly evolving subject."
Download or read book Lightcone Qcd And Nonperturbative Hadron Physics Conf written by Andreas W Schreiber and published by World Scientific. This book was released on 2000-10-25 with total page 325 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains the proceedings of the 'Workshop on Lightcone QCD and Nonperturbative Hadron Physics', held in Adelaide, Australia, in December 1999. The contributions include papers on vacuum structure and zero modes, DLCQ, deep inelastic scattering, lightcone wavefunctions and hadron structure, hadron phenomenology, as well as numerical results from the lattice for both quenched and unquenched QCD.
Download or read book Gdh 2000 The Gerasimov drell hearn Sum Rule The Nucleon Spin Structure In The Resonance Region written by Dieter Drechsel and published by World Scientific. This book was released on 2001-02-05 with total page 430 pages. Available in PDF, EPUB and Kindle. Book excerpt: The history of spin in general, and of the nucleon spin structure in particular, has been full of surprises. For the past 25 years deep inelastic lepton scattering has been studied to determine the carriers of the nucleon spin. However, it was realized only recently that a full understanding of the nucleon spin will also require detailed information on the helicity structure in the resonance region, i.e. in the realm of nonperturbative QCD.This volume gives a status report on the spin structure in the nucleon resonance region, focusing on: new experimental results from SLAC and HERMES; a first glance at the JLab experiments to map out the spin structure functions at low and intermediate four-momentum transfers; the pioneering experiment at MAMI (Mainz) to determine the Gerasimov-Drell-Hearn sum rule for real photons; and recent theoretical concepts and investigations to describe the spin structure in the frameworks of higher twist expansion, phenomenological models and chiral perturbation theory.
Download or read book The 9th International Workshop on Deep Inelastic Scattering DIS 2001 written by G. Bruni and published by World Scientific. This book was released on 2002 with total page 882 pages. Available in PDF, EPUB and Kindle. Book excerpt: The proceedings of DIS 2001 present the most updated status of deep inelastic scattering (DIS) physics. Topics like structure function measurements and phenomenology, 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 the lepton-proton scattering. Moreover, this workshop coincided with the transition between the first period of experimentation at the HERA ep collider at DESY and the start of the updated HERA II operation -- allowing a review of what has been learned up to now and a discussion on the main future directions of research in this field.
Download or read book Twist 3 Fragmentation Effects for ALT in Light Hadron Production from Proton proton Collisions written by and published by . This book was released on 2015 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: Here, we compute the contribution from the twist-3 fragmentation function for light hadron production in collisions between transversely and longitudinally polarized protons, i.e., View the MathML sourcep↑p→→hX, which can cause a double-spin asymmetry (DSA) ALT. This is a naïve T-even twist-3 observable that we analyze in collinear factorization using both Feynman gauge and lightcone gauge as well as give a general proof of color gauge invariance. So far only twist-3 effects in the transversely polarized proton have been studied for ALT in p↑p→→hX. However, there are indications that the naïve T-odd transverse single-spin asymmetry (SSA) AN in p↑p→hX is dominated not by such distribution effects but rather by a fragmentation mechanism. Therefore, one may expect similarly that the fragmentation contribution is important for ALT. As a result, given possible plans at RHIC to measure this observable, it is timely to provide a calculation of this term.
Download or read book Baryons 2002 Proceedings Of The 9th International Conference On The Structure Of Baryons written by Bernhard Mecking and published by World Scientific. This book was released on 2003-05-28 with total page 705 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book deals with the latest developments in the area of three-quark systems. Emphasis is given to the discussion of new experimental results in the areas of form factors, unpolarized and polarized structure functions, and baryon structure and spectroscopy. Of particular interest are the new theoretical developments in the area of generalized parton distributions and lattice quantum chromodynamics.
Download or read book Probing Nucleons And Nuclei In High Energy Collisions Proceedings Of The Int Program Int 18 3 written by Alexei Prokudin and published by World Scientific. This book was released on 2020-05-29 with total page 344 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book contains proceedings of the 7-week INT program dedicated to the physics of the Electron-Ion Collider (EIC), the world's first polarized electron-nucleon (ep) and electron-nucleus (eA) collider to be constructed in the United States. The 2015 NSAC Long Range Plan recommended EIC as the 'highest priority for new facility construction following the completion of FRIB'. The primary goal of the EIC is to establish precise multi-dimensional imaging of quarks and gluons inside nucleons and nuclei. This includes (i) understanding the spatial and momentum space structure of the nucleon through the studies of TMDs (transverse-momentum-dependent parton distributions), GPD (generalized parton distributions) and the Wigner distribution; (ii) determining the partonic origin of the nucleon spin; (iii) exploring the new quantum chromodynamics (QCD) frontier of ultra-strong gluon fields, with the potential to seal the discovery of a new form of dense gluon matter predicted to exist in all nuclei and nucleons at small Bjorken x — the parton saturation.The program brought together both theorists and experimentalists from Jefferson Lab (JLab), Brookhaven National Laboratory (BNL) along with the national and international nuclear physics communities to assess and advance the EIC physics.
Download or read book Baryons 2002 written by Carl Carlson and published by World Scientific. This book was released on 2003 with total page 712 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book deals with the latest developments in the area of three-quark systems. Emphasis is given to the discussion of new experimental results in the areas of form factors, unpolarized and polarized structure functions, and baryon structure and spectroscopy. Of particular interest are the new theoretical developments in the area of generalized parton distributions and lattice quantum chromodynamics.
Download or read book Transverse Spin Physics written by Dr. Vincenzo Barone and published by World Scientific. This book was released on 2003 with total page 308 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study deals with the theory and phenomenology of transverse spin effects in high-energy hadronic physics. Contrary to common past belief, it is now rather clear that these effects are far from irrelevant. A decade or so of intense theoretical work has shed much light on the subject and brought to the surface an entire class of new phenomena, which now await thorough experimental investigation. Over the next few years a number of experiments worldwide (at DESY, CERN and Brookhaven) will run with transversely polarised particles, providing data that will enrich our knowledge of the transverse spin structure of hadrons. The principle aim of this work is to assess the state of the art as it stands in 2002. After a few introductory remarks (Chapter 1), in the first part (Chapters 2-4) attention is directed to polarised deep inelastic scattering (DIS), particularly DIS on transversely polarised targets, which probes the transverse spin structure function g2. This structure function is examined within the framework of the quark-parton model and its improvement via perturbative QCD. The existing data are reviewed and commented on (for completeness and comparison, a brief presentation of longitudinally polarised DIS and of the helicity structure of the proton is provided). The second part of the book (Chapters 5-8) focuses on the transverse polarisation of quarks, the so-called "transversity". The partonic content and the QCD evolution of the transversity distributions are presented in detail. The phenomenology of transversity is then studied in the context of Drell-Yan processes and of semi-inclusive lepto- and hadroproduction. The interpretation of data on single-spin asymmetries is discussed and, finally, the prospects for future measurements are reviewed.
Download or read book Nuclear Physics written by and published by . This book was released on 2002 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt:
