Determining the helicity structure of the nucleon at the Electron Ion Collider in China

Abstract

Understanding how sea quarks behave inside a nucleon is one of the most important physics goals of the proposed Electron-Ion Collider in China (EicC), which is designed to have a 3.5 GeV polarized electron beam (80% polarization) colliding with a 20 GeV polarized proton beam (70% polarization) at instantaneous luminosity of 2 × 1033cm−2s−1. A specific topic at EicC is to understand the polarization of individual quarks inside a longitudinally polarized nucleon. The potential of various future EicC data, including the inclusive and semi-inclusive deep inelastic scattering data from both doubly polarized electron-proton and electron-3He collisions, to reduce the uncertainties of parton helicity distributions is explored at the next-to-leading order in QCD, using the Error PDF Updating Method Package (ePump) which is based on the Hessian profiling method. We show that the semi-inclusive data are well able to provide good separation between flavour distributions, and to constrain their uncertainties in the x > 0.005 region, especially when electron-3He collisions, acting as effective electron-neutron collisions, are taken into account. To enable this study, we have generated a Hessian representation of the DSSV14 set of PDF replicas, named DSSV14H PDFs.

Study of MIPs effects on a MAPS for electron ion collider in China

“…The Electron-ion collider in China (EicC) [1] is a future high-energy nuclear physics facility with the main focus on precision measurements of the structure of the nucleon in the sea quark region. The EicC will be constructed based on an upgraded heavy-ion accelerator, High-Intensity heavyion Accelerator Facility (HIAF), which is currently under construction, together with a new electron ring.…”

Matching generalised transverse-momentum-dependent distributions onto generalised parton distributions at one loop

“…Phenomenological determinations of GPDs do exist [25][26][27], but as of today, they are much less developed than mod-ern analyses of PDFs/FFs and TMDs. However, the recent approval of the electron-ion colliders in China (EicC) [28] and in the USA (EIC) [29], has revived the interest in GPDs that is now a rapidly growing field. In addition, new technologies on the lattice [30,31] have made first-principle computations of GPDs more accessible, giving additional momentum to their study.…”

Highlights of pion and kaon structure from continuum analyses

“…On the eve of next generation experiments with meson targets [15][16][17][18], which would expose an array of structural properties of pions and kaons, robust theoretical predictions and explanations must be readily available. Our present analysis is based upon Ref.…”