Unveiling the Proton Spin Decomposition at a Future Electron-Ion Collider

We present a detailed assessment of how well a future Electron-Ion Collider could constrain helicity parton distributions in the nucleon and, therefore, unveil the role of the intrinsic spin of quarks and gluons in the proton's spin budget. Any remaining deficit in this decomposition will provide the best indirect constraint on the contribution due to the total orbital angular momenta of quarks and gluons. Specifically, all our studies are performed in the context of global QCD analyses based on realistic pseudo-data and in the light of the most recent data obtained from polarized proton-proton collisions at BNL-RHIC that have provided evidence for a significant gluon polarization in the accessible, albeit limited range of momentum fractions. We also present projections on what can be achieved on the gluon's helicity distribution by the end of BNL-RHIC operations. All estimates of current and projected uncertainties are performed with the robust Lagrange multiplier technique.Comment: 12 pages, 8 eps figure

Global analysis of helicity PDFs: past - present - future

We discuss the current status of the DSSV global analysis of helicity-dependent parton densities. A comparison with recent semi-inclusive DIS data from COMPASS is presented, and constraints on the polarized strangeness density are examined in some detail.Comment: Talk presented at the XIX Int. Workshop on Deep-Inelastic Scattering and Related Subjects (DIS 2011); 4 pages; 2 figure

Global extraction of the parton-to-pion fragmentation functions at NLO accuracy in QCD

In this review, we discuss the results on the parton-to-pion fragmentation functions obtained in a combined NLO fit to data of single-inclusive hadron production in electron-positron annihilation, proton-proton collisions, and lepton-nucleon deep-inelastic scattering. A more complete discussion can be found in Ref. [1].Comment: 6 pages, 1 figure. To be published in Journal of Physics Conference Series (IOP). Joint Proceedings of the XV Mexican Workshop on Particles and Fields & the XXX Annual Meeting of the Division of Particles and Fields of the Mexican Physical Societ

Nuclear PDFs

We present the latest global QCD analysis of nuclear parton distribution functions. The emerging picture is one of consistency, with universal nuclear modification factors reproducing the main features of the data. Differences with previous analyses are addressed

Global extraction of the parton-to-pion fragmentation functions at NLO accuracy in QCD

In this review, we discuss the results on the parton-to-pion fragmentation functions obtained in a combined NLO fit to data of single-inclusive hadron production in electron-positron annihilation, proton-proton collisions, and lepton-nucleon deep-inelastic scattering.Facultad de Ciencias ExactasInstituto de Física La Plat

Global extraction of the parton-to-kaon fragmentation functions at NLO in QCD

In this document, we present the global QCD analysis of parton-to-kaon fragmentation functions at next-to-leading order accuracy using the latest experimental information on single-inclusive kaon production in electron-positron annihilation, lepton-nucleon deep-inelastic scattering, and proton-proton collisions. An extended analysis of this work can be found in Ref. [1].Instituto de Física La Plat

Global extraction of the parton-to-pion fragmentation functions at NLO accuracy in QCD

In this review, we discuss the results on the parton-to-pion fragmentation functions obtained in a combined NLO fit to data of single-inclusive hadron production in electron-positron annihilation, proton-proton collisions, and lepton-nucleon deep-inelastic scattering.Facultad de Ciencias ExactasInstituto de Física La Plat

Soffer's inequality and the transversely polarized Drell-Yan process at next-to-leading order

We check numerically if Soffer's inequality for quark distributions is preserved by next-to-leading order QCD evolution. Assuming that the inequality is saturated at a low hadronic scale we estimate the maximal transverse double spin asymmetry for Drell-Yan muon pair production to next-to-leading order accuracy.Comment: 20 Pages, LaTeX, 7 figures as eps file