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Full-Text Articles in Physics
Definition Of Fragmentation Functions And The Violation Of Sum Rules, John Collins, Ted C. Rogers
Definition Of Fragmentation Functions And The Violation Of Sum Rules, John Collins, Ted C. Rogers
Physics Faculty Publications
We point out a problem with the formulation and derivations of sum rules for quark fragmentation functions that impacts their validity in QCD, but which potentially points toward an improved understanding of final states in inclusive hard processes. Fragmentation functions give the distribution of final-state hadrons arising from a parton exiting a hard scattering, and the sum rules for momentum, electric charge, etc. express conservation of these quantities. The problem arises from a mismatch between the quark quantum numbers of the initial quark and the fact that all observed final-state hadrons are confined bound states with color zero. We point …
Full Treatment Of The Thrust Distribution In Single Inclusive E⁺E⁻ → H X Processes, M. Boglione, Andrea Simonelli
Full Treatment Of The Thrust Distribution In Single Inclusive E⁺E⁻ → H X Processes, M. Boglione, Andrea Simonelli
Physics Faculty Publications
Extending the transverse momentum dependent factorization to thrust dependent observables entails a series of difficulties, ultimately associated to the behavior of soft radiation. As a consequence, the definition of the transverse momentum dependent functions has to be revised, while preserving (and possibly extending) their universality properties. Moreover, the regularization of the rapidity divergences generates non trivial correlations between rapidity and thrust. In this paper, we show how to deal with these correlations in a consistent treatment of the thrust dependence of e+e− → h X cross section, where the hadron transverse momentum is measured with respect to …
Neural-Network Analysis Of Parton Distribution Functions From Ioffe-Time Pseudodistributions, Luigi Del Debbio, Tommaso Giani, Joseph Karpie, Kostas Orginos, Anatoly Radyushkin, Savvas Zafeiropoulos
Neural-Network Analysis Of Parton Distribution Functions From Ioffe-Time Pseudodistributions, Luigi Del Debbio, Tommaso Giani, Joseph Karpie, Kostas Orginos, Anatoly Radyushkin, Savvas Zafeiropoulos
Physics Faculty Publications
We extract two nonsinglet nucleon Parton Distribution Functions from lattice QCD data for reduced Ioffe-time pseudodistributions. We perform such analysis within the NNPDF framework, considering data coming from different lattice ensembles and discussing in detail the treatment of the different source of systematics involved in the fit. We introduce a recipe for taking care of systematics and use it to perform our extraction of light-cone PDFs.
Gluon Tmd In Particle Production From Low To Moderate X, I. Balitsky, A. Tarasov
Gluon Tmd In Particle Production From Low To Moderate X, I. Balitsky, A. Tarasov
Physics Faculty Publications
We study the rapidity evolution of gluon transverse momentum dependent distributions appearing in processes of particle production and show how this evolution changes from small to moderate Bjorken x.
Measurement Of The Emc Effect In The Deuteron, K. A. Griffioen, J. Arrington, M. E. Christy, R. Ent, N. Kalantarians, C. E. Keppel, S E. Kuhn
Measurement Of The Emc Effect In The Deuteron, K. A. Griffioen, J. Arrington, M. E. Christy, R. Ent, N. Kalantarians, C. E. Keppel, S E. Kuhn
Physics Faculty Publications
We determined the structure function ratio RdEMC=Fd2/(Fn2+Fp2) from recently published Fn2/Fd2 data taken by the BONuS experiment using CLAS at Jefferson Lab. This ratio deviates from unity, with a slope dRdEMC/dx=−0.10 ± 0.05 in the range of Bjorken x from 0.35 to 0.7, for invariant mass W>1.4 GeV and Q2>1 GeV2 . The observed EMC effect for these kinematics is consistent with conventional nuclear physics models that include off-shell corrections, as well as with empirical analyses …
Measurement Of Exclusive Πº Electroproduction Structure Functions And Their Relationship To Transverse Generalized Parton Distributions, Clas Collaboration, K. P. Adhikari, M. J. Amaryan, R. P. Bennett, S. Koirala, S. E. Kuhn, M. Mayer, L. B. Weinstein, I. Bedlinsky, V. Kubarovsky
Measurement Of Exclusive Πº Electroproduction Structure Functions And Their Relationship To Transverse Generalized Parton Distributions, Clas Collaboration, K. P. Adhikari, M. J. Amaryan, R. P. Bennett, S. Koirala, S. E. Kuhn, M. Mayer, L. B. Weinstein, I. Bedlinsky, V. Kubarovsky
Physics Faculty Publications
Exclusive π0 electroproduction at a beam energy of 5.75 GeV has been measured with the Jefferson Lab CLAS spectrometer. Differential cross sections were measured at more than 1800 kinematic values in Q2, xB , t , and ϕπ , in the Q2 range from 1.0 to 4.6 GeV2 , −t up to 2 GeV2 , and xB from 0.1 to 0.58. Structure functions σT+ϵσL , σTT , and σLT were extracted as functions of t for each of 17 combinations of Q2 and xB . …
W-Boson Production With Large Transverse Momentum At The Lhc, Nikolaos Kidonakis, Richard J. Gonsalves, Agustin Sabio Vera
W-Boson Production With Large Transverse Momentum At The Lhc, Nikolaos Kidonakis, Richard J. Gonsalves, Agustin Sabio Vera
Faculty and Research Publications
We study W-boson production with large transverse momentum, QT, in pp collisions at the LHC. We calculate the complete NLO corrections and the soft-gluon NNLO corrections to the differential cross section. The NLO corrections are large but they do not reduce the scale dependence relative to LO, while the NNLO soft-gluon corrections, although small, significantly reduce the scale dependence and thus provide a more stable result.
Soft-Gluon Corrections In Hard-Scattering Processes Through Nnnlo, Nikolaos Kidonakis
Soft-Gluon Corrections In Hard-Scattering Processes Through Nnnlo, Nikolaos Kidonakis
Faculty and Research Publications
I discuss soft-gluon corrections in hard-scattering processes and their resummation. I present master formulas for the expansion of the resummed cross section through NNNLO and discuss the significance of these corrections in a number of processes.
Charged Higgs Production: Higher-Order Corrections, Nikolaos Kidonakis
Charged Higgs Production: Higher-Order Corrections, Nikolaos Kidonakis
Faculty and Research Publications
I present a calculation of higher-order radiative corrections to charged Higgs production in association with a top quark via the process bg -> tH-. Results for charged Higgs production at the LHC are presented, including the dependence of the cross section on the charged Higgs mass, the top quark mass, the factorization and renormalization scales, and tan beta. I show that the theoretical prediction for the cross section is significantly enhanced and is greatly stabilized when the higher-order corrections are included.
How Much Of The Nucleon Spin Is Carried By Glue?, Ian Balitsky, Xiangdong Ji
How Much Of The Nucleon Spin Is Carried By Glue?, Ian Balitsky, Xiangdong Ji
Physics Faculty Publications
We estimate in the QCD sum rule approach the amount of the nucleon spin carried by the gluon angular momentum: the sum of the gluon spin and orbital angular momenta. The result indicates that gluons contribute at least one half of the nucleon spin at the scale of 1GeV2.