1. Contalbrigo Marco INFN Ferrara QCD Evolution 13 7 th May 2013, JLab – Newport News

2. Spin degrees of freedom can explain otherwise surprising phenomena and bring new insights into nuclear matter structure e p → e p PRC 68, 034325 (2003) xFxF Fundamental: do not neglect it !! 2 Contalbrigo M. QCD Evolution Workshop, 7 th May 2013, JLab

3. In our exploration of the QCD micro-world Fundamental: do not neglect spin !! 3 Contalbrigo M. Two questions in Hadronic Physics await explanation since too long p T < 2 GeV/c √s = 20 GeV xFxF ANAN Proton Spin Budget Single Spin Asymmetries ? QCD Evolution Workshop, 7 th May 2013, JLab

4. PDFs f p u (x),… TMD PDFs: f p u (x,k T ),… d2kTd2kT  =0,t=0 W p q (x,k T,r) “Mother” Wigner distributions d3rd3r d2kTd2kT Exclusive Measurements Momentum transfer to target Direct info about spatial distribution Semi-inclusive measurements Momentum transfer to quark Direct info about momentum distribution (FT) GPDs: H p u (x, ,t), … p T < 2 GeV/c √s = 20 GeV xFxF ANAN May solve proton spin puzzle May explain SSA & Lam-Tung Probability to find a quark q in a nucleon P with a certain polarization in a position r & momentum k 4 Contalbrigo M. QCD Evolution Workshop, 7 th May 2013, JLab

5. 5 Contalbrigo M. QCD Evolution Workshop, 7 th May 2013, JLab EIC

6. Limit defined by luminosity 10 32 10 31 10 35 Different Q 2 for same x range EIC 10 34 Valence Complementary experiments Sea 6 Contalbrigo M. QCD Evolution Workshop, 7 th May 2013, JLab

8. 6 GeV CEBAF CHL-2 Upgrade magnets and power supplies 12 GeV CEBAF Enhance equipment in existing halls add Hall D (and beam line) 2008-2014: Construction (funded at 99%) May 2012 6 GeV Accelerator Shutdown starts May 2013 Accelerator Commissioning starts October 2013 Hall Commissioning starts 2013-2015 Pre-Ops (beam commissioning) Beam current 90  A Beam polarization 85 % 8 Contalbrigo M. QCD Evolution Workshop, 7 th May 2013, JLab

11. 11 Contalbrigo M. Super High Momentum Spectrometer (SHMS) unpolarized SIDIS, hadron ID Hall-C Spectrometer Pair, polarized 3 He target up to to 10 38 cm -2 s -1 hadron ID Hall-A Hall-B CLAS12 H,D polarized targets up to 10 35 cm -2 s -1 “complete” acceptance, hadron ID SOLID 3 He, NH 3 polarized targets up to 10 36 cm -2 s -1 large acceptance, pion ID Hall-A QCD Evolution Workshop, 7 th May 2013, JLab

13. 13 Contalbrigo M. Super-HMS 11 GeV/c spectrometer 5 o -25 o angular range e/h,  /K ID by Cherenkov HMS 7 GeV/c spectrometer 10 o -90 o angular range e/h,  /K ID by Cherenkov QCD Evolution Workshop, 7 th May 2013, JLab SIDIS cross-section factorization tests

14. DC R3 R2 R1 DC R3 R2 R1 EC Torus FTOF PCAL HTCC Solenoid 14 Contalbrigo M. Luminosity up to 10 35 cm -2 s -1 Broad kinematic range coverage (current to target fragmentation) TOF + RICH for hadron ID H and D polarized targets Highly polarized electron beam RICH QCD Evolution Workshop, 7 th May 2013, JLab TMDs and GPDs comprehensive study, with special care on applicability

15. 15 Contalbrigo M. Intermediate anguar range (15-25 o ) mandatory to reach high P T values Large electron scattering angles (> 20 o ) mandatory to reach high Q 2 values Electron The CLAS12 forward detector is perfectly suitable for high-Q 2 and high-p T measurements since designed to cover up to 40 degrees angles Electron ++ acceptance QCD Evolution Workshop, 7 th May 2013, JLab

16. Advantages:  Minimize nuclear background smaller dilution, no attenuation at large p T  Weak holding field (BdL ~ 0.1 Tm) wide acceptance, negligible beam deflection Disadvantages:  Very long polarizing times (months)  Sensitivity to local heating by charged beams HD-Ice target vs standard nuclear targets (less luminosity for higher purity) 16 Contalbrigo M. HD-ice ran from Nov/11 to May/12 at Jlab R&D work required to run with electron beams E06-101 up to 10 8  /s T1 ~ years Deuterium dilution is under control Suitable for di-hadron and recoil proton Ph2Ph2 T R QCD Evolution Workshop, 7 th May 2013, JLab

17. 17 Contalbrigo M. Present: spectrometer pair Future: large acceptance detector QCD Evolution Workshop, 7 th May 2013, JLab High-luminosity 3 He target GEM trackers PID challenging Ultimate statistical precision in the valence region

18. 18 Contalbrigo M. QCD Evolution Workshop, 7 th May 2013, JLab

20. ULT U L T Quark polarisation Nucleon polarisation Sivers Pretzelosity Worm-gear Collinear physics tensor charge 20 Contalbrigo M. D-wave component not-spherical shape of the nucleon Orbital quark motion non-trivial gauge link process dependence Proton wave components with different OAM Worm-gear Proton wave components with different OAM Spin effects in unpolarized reactions Number Density Helicity Transversity Boer Mulders p T dependence of quark helicity p T dependence of number density QCD Evolution Workshop, 7 th May 2013, JLab

21. N/q ULT U L T quark polarisatio n nucleon polarisation Number Helicity Sivers Boer-Mulders Density Worm-gear 21 Contalbrigo M. Transversity DFDF FF Pretzelosity SIDIS cross section (transversely pol. target): Involved phenomenology due to the convolution over transverse momentum TMD factorization for P T <<Q QCD Evolution Workshop, 7 th May 2013, JLab

22. 22 Contalbrigo M. R DIS  0 at Q 2  ∞ due to scattering off spin-½ quarks R DIS sensitive to gluon and higher-twist effects R SIDIS (z,pT) = un-integrated R DIS To be accounted in any TMD asymmetry interpretation QCD Evolution Workshop, 7 th May 2013, JLab Cornell data of 70’s E12-06-104 Hall-C

23. At p T > 0.2 GeV/c use dependencies measured in CLAS12 experiment 23 Contalbrigo M. Map pf p T dependence for pion off proton and deuteron targets QCD Evolution Workshop, 7 th May 2013, JLab E12-09-017 Hall-C Hall C - JLab

24. Perturbative region Collinear factorization Non-perturbative TMD factorization 24 Contalbrigo M. QCD Evolution Workshop, 7 th May 2013, JLab Boer-Mulders spin-orbit effect E12-06-112 Hall-B

25. Band: Phys Rev D78 034035 Boer-Mulders from DY data Collins from chiral limit Line: Phys Rev D78 045022 Boer-Mulders from Sivers Collins from e+e- data kaon 25 Contalbrigo M. QCD Evolution Workshop, 7 th May 2013, JLab E12-09-008 Hall-B In the perturbative limit 1/P T behavior expected A LU ~ 1/Q (Twist-3) Measurements of kinematic (x,Q 2,z,P T ) will probe HT distribution functions E12-06-112 Hall-B ep  e’ KX

26. kaon 26 Contalbrigo M. QCD Evolution Workshop, 7 th May 2013, JLab E12-09-008 Hall-B In the perturbative limit 1/P T behavior expected A LU ~ 1/Q (Twist-3) Measurements of kinematic (x,Q 2,z,P T ) will probe HT distribution functions E12-06-112 Hall-B ep  e’ KX

27. 27 Contalbrigo M. QCD Evolution Workshop, 7 th May 2013, JLab E12-07-104 Hall-B E12-06-109 Hall-B E12-06-122 Hall-A E12-06-110 Hall-C Transverse momentum dependence of quark helicity vs number density Quark helicity at high-x is sensitive to orbital angular momentum.

28. 28 Contalbrigo M. QCD Evolution Workshop, 7 th May 2013, JLab E12-07-104 Hall-B

29. 29 Contalbrigo M. 1 st collinear extraction ! 1 st extraction of Transversity! Anselmino et al. Phys. Rev. D 75 (2007) Soffer bound xh 1 (x) d u xh 1 (x, k ) T u T d Bacchetta et al., PRL 107 (2011) NO DATA Gauss Ansatz High-x and tensor charge Gaussian ansatz & role of Q 2 evolution ? QCD Evolution Workshop, 7 th May 2013, JLab

30. 30 Contalbrigo M. Non zero signals for  + and K + Significant Q 2 evolution ? K + signals larger than  + ? K+-K+- T3 correlator from pp Sivers moment from SIDIS Sign change is a crucial test of TMDs factorization Coverage at large x and relation with Drell-Yan Sign mismatch between SIDIS and pp SSA ? Coverage at large p T and x and relation with twist-3 collinear approach HERMES p ? ? x arXiv:1112.4423 arXiv:1107.4446 Related to quark orbital angular momentum QCD Evolution Workshop, 7 th May 2013, JLab

31. 31 Contalbrigo M. Collins asymmetry Large x important to constrain the tensor charge Sivers asymmetry High resolution and broad range in p T to test perturb. non-perturb. transient and for Bessel function analysis QCD Evolution Workshop, 7 th May 2013, JLab C12-11-111 Hall-B

32. 32 Contalbrigo M. Statistical errors 4D analysis on  + QCD Evolution Workshop, 7 th May 2013, JLab

33. 33 Contalbrigo M. QCD Evolution Workshop, 7 th May 2013, JLab Q 2 dependence of Sivers asymmetry Test of TMDs evolution Di-hadron channel for h 1 Test of TMDs extraction E12-12-109 Hall-B Sensitivity to so-far not-observed distributions C12-11-111 Hall-B

34. 34 Contalbrigo M. Precise 3D measurement on 3 He with hadron ID ✓ neutron TMD ✓ flavor separation )X 40 days QCD Evolution Workshop, 7 th May 2013, JLab E12-11-007 Hall-A

35. 35 Contalbrigo M. A UT A UL QCD Evolution Workshop, 7 th May 2013, JLab Luminosity: up to 10 36 cm -2 s -1 Acceptance: Electron 8-26 degrees Pion 8-16 degrees Forward detector Large angle detector E12-10-006 Hall-A E12-11-007 Hall-A A UT A UL

36. 36 Contalbrigo M. C12-11-108 Hall-A J.-P. Chen QCD Evolution Workshop, 7 th May 2013, JLab

38. Encompass parton distributions and form factors Longitudinal momentum and transverse spatial position correlated information Access OAM L q = J q -½  via Ji sum rule 38 Contalbrigo M. QCD Evolution Workshop, 7 th May 2013, JLab

39. 39 Contalbrigo M. QCD Evolution Workshop, 7 th May 2013, JLab Inconsistency in DATA ? Diehl et al. arXiv: 1302.4604 Bacchetta et al. arXiv: 1107.5755

40. 40 Contalbrigo M. QCD Evolution Workshop, 7 th May 2013, JLab Ratio of quasi-elastic e-p to e-n scatterings off a deuteron target Related to GPDs at high |t|  structure of the nucleon at small transverse distances E12-09-019 Hall-A E12-07-104 Hall-B

41. 41 Contalbrigo M. QCD Evolution Workshop, 7 th May 2013, JLab Ratio of recoil polarizations E12-11-009 Hall-C Asymmetry in quasi-elastic scattering E12-09-016 Hall-A E12-07-109 Hall-A

42. 42 Contalbrigo M. QCD Evolution Workshop, 7 th May 2013, JLab E12-06-114 Hall-A

43. 43 Contalbrigo M. 120 days beam time A UL Q2Q2 Q2Q2 x x A LU -t 85 days beam time QCD Evolution Workshop, 7 th May 2013, JLab C12-06-119 Hall-B

44. 44 Contalbrigo M. QCD Evolution Workshop, 7 th May 2013, JLab C12-12-010 Hall-B A LT A UT A LT A UT

45. 45 Contalbrigo M. QCD Evolution Workshop, 7 th May 2013, JLab E12-11-003 Hall-B

46. 46 Contalbrigo M. QCD Evolution Workshop, 7 th May 2013, JLab

47. 47 Contalbrigo M. QCD Evolution Workshop, 7 th May 2013, JLab E12-07-105 Hall-C E12-09-011 Hall-C

48. 48 Contalbrigo M. QCD Evolution Workshop, 7 th May 2013, JLab From t slope  average impact parameter E12-12-107 Hall-B

49. 49 Contalbrigo M. Complete mapping (3D) of the nucleon in the valence region High potential of the complementary programs of 3 experimental halls QCD Evolution Workshop, 7 th May 2013, JLab Start of Accelerator commissioning expected in November and running beam to Hall-A in February 2014