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Small-x Helicity Phenomenology

ORAL

Abstract

One of the key components to solving the proton spin problem is understanding the small-x asymptotics of the helicity parton distribution functions (hPDFs). Several years ago, novel, small-x evolution equations were derived using the shock-wave/Wilson line formalism, designed for calculating the x-dependence of the quark and gluon hPDFs and the proton g1 structure function. These equations can be used to predict the contribution to the spin of the proton coming from the helicities of the small-x quarks and gluons. In this talk we will present the first-ever attempt to describe the world data on the g1 structure function at small x using the evolution equations derived the novel evolution equations within the JAM global analysis framework. Our results serve as a prediction for future measurements at the EIC and can be used to estimate the net amount of quark spin at small-x, ultimately bringing us one step closer to understanding the proton spin. *This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics under Award Number DE-SC0004286.

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Authors

  • Daniel Adamiak

    Ohio State Univ - Columbus

  • Yuri Kovchegov

    The Ohio State University, Ohio State Univ - Columbus

  • Samantha Hudson

    Liverpool, Konkoly, STScI, PMO, SKA, Yale, National Superconducting Cyclotron Laboratory, Western Michigan University, School of Physics, Peking University, NSCL, Department of Physics, Korea University, Rare Isotope Science Project, Institute for Basic Science, Daejeon, Department of Physics, Western Michigan University, Korea University, Riken, Kyoto University, NCSL, New Mexico State University, Jefferson Lab, Lebanon Valley College, Lawrence Berkeley National Laboratory, Youngstown State University, Cleveland State University, Department of Physics, SUNY Buffalo State, Buffalo, NY 14222 USA, Department of Physics, SUNY Buffalo State, Buffalo, NY 14222

  • Samantha Hudson

    Liverpool, Konkoly, STScI, PMO, SKA, Yale, National Superconducting Cyclotron Laboratory, Western Michigan University, School of Physics, Peking University, NSCL, Department of Physics, Korea University, Rare Isotope Science Project, Institute for Basic Science, Daejeon, Department of Physics, Western Michigan University, Korea University, Riken, Kyoto University, NCSL, New Mexico State University, Jefferson Lab, Lebanon Valley College, Lawrence Berkeley National Laboratory, Youngstown State University, Cleveland State University, Department of Physics, SUNY Buffalo State, Buffalo, NY 14222 USA, Department of Physics, SUNY Buffalo State, Buffalo, NY 14222

  • Samantha Hudson

    Liverpool, Konkoly, STScI, PMO, SKA, Yale, National Superconducting Cyclotron Laboratory, Western Michigan University, School of Physics, Peking University, NSCL, Department of Physics, Korea University, Rare Isotope Science Project, Institute for Basic Science, Daejeon, Department of Physics, Western Michigan University, Korea University, Riken, Kyoto University, NCSL, New Mexico State University, Jefferson Lab, Lebanon Valley College, Lawrence Berkeley National Laboratory, Youngstown State University, Cleveland State University, Department of Physics, SUNY Buffalo State, Buffalo, NY 14222 USA, Department of Physics, SUNY Buffalo State, Buffalo, NY 14222

  • Samantha Hudson

    Liverpool, Konkoly, STScI, PMO, SKA, Yale, National Superconducting Cyclotron Laboratory, Western Michigan University, School of Physics, Peking University, NSCL, Department of Physics, Korea University, Rare Isotope Science Project, Institute for Basic Science, Daejeon, Department of Physics, Western Michigan University, Korea University, Riken, Kyoto University, NCSL, New Mexico State University, Jefferson Lab, Lebanon Valley College, Lawrence Berkeley National Laboratory, Youngstown State University, Cleveland State University, Department of Physics, SUNY Buffalo State, Buffalo, NY 14222 USA, Department of Physics, SUNY Buffalo State, Buffalo, NY 14222