Proton Spin in the EIC Era EIC Panel Discussion
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Proton Spin in the EIC Era EIC Panel Discussion Feng Yuan* Lawrence Berkeley National Laboratory Electron Ion Collider Users Meeting Stony Brook University, June 24-27 2014 *discussions with Ernst Sichterma
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Proton Spin in the EIC Era EIC Panel Discussion. Feng Yuan* Lawrence Berkeley National Laboratory. Electron Ion Collider Users Meeting Stony Brook University, June 24-27 2014. *discussions with Ernst Sichtermann. - PowerPoint PPT Presentation
Transcript of Proton Spin in the EIC Era EIC Panel Discussion
Proton Spin in the EIC EraEIC Panel Discussion
Feng Yuan* Lawrence Berkeley National Laboratory
Electron Ion Collider Users MeetingStony Brook University, June 24-27 2014
*discussions with Ernst Sichtermann
quark spin × 2
gluo
n sp
inPrecision constraints on the parton helicity contributions in the nucleon spin:
NNPDF, arXiv:1406.5539 (June 20th): =
With positive contributions fromRHIC measured range:
=
based on additional (2009) data.
See also DSSV, arXiv:1404.4293.
Parton Orbital Motion from nucleon tomography:
• Spin measurements at EIC will extend not only the range in x and Q2, but will also enable 2+1D imaging of quarks and gluons.
k y
kx
-0.5
0.5
0.0
0.0-0.5 0.5
Fundamental Understandingof
the Nucleon Spin and the Role of Spin in QCD
Theory/Phenomenology
Lattice QCD Detmold’s talk recent developments: Ji, 2013, Lin, et al, 2014 Ma, Qiu, 2014, Ji-Sun-Xiong-Yuan, 2014 (TMDs)
EIC Measurements
Back-up
Wide Q2 Range Crucial for TMDs
Leading power TMD
Non-singular term in CSS(power corrections)
TMD factorization in quasi-pdfs
• For example, for Drell-Yan lepton pair production
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Lattice calculationQuasi-pdfs
Soft factor
