1. 核子结构的 “ 新 ” 图像 陈相松 四川大学 华中科技大学

2. 提要 核子结构研究的目标 终极目标与阶段性目标 核子结构图像的 “ 演化 ” ： 原始图像、 “ 标准 ” 图像、 “ 新 ” 图像 [1]Phys.Rev.Lett.100:032002(2008) [2]Phys.Rev.Lett.103:062001(2009) 季向东的 Comment 与我们的 Reply [1] 评 :arXiv:0810.4913 答 :arXiv:0812.4336 [2] 评 :arXiv:0910.5022 答 :arXiv:0911.0248

3. 核子结构研究的目标 终极目标：对核子的完备描写 完备：预言核子参与所有反应的结果 硬过程： Parton Distribution Functions 阶段性目标：核子质量、动量、自旋、 磁矩的夸克 - 胶子起源

4. 核子结构图像的 “ 演化 ” 原始图像：组分夸克模型：质子 =(uud) “ 标准 ” 图像：质子 =~50% 夸克 +~50% 饺子 理论： Politzer, Phys.Rep. 14:129 (1974) Gross & Wilczek, PRD9:980 (1974) Georgi & Politzer, PRD9:416 (1974) 实验： Sloan, Smadja & Voss, Phys.Rep. 162:46(1988) 理论： X. Ji et al., PRL76:740 (1996) 实验： EMC: 夸克自旋 ( 最新数据： 20-30%) COMPASS, PHENIX: 胶子自旋 (~0)

5. “ 标准 ” 乎？ 不相匹配的动量与角动量

6. “ 强行匹配 ” 的规范不变障碍

7. 新方法：规范场的物理分解

8. 物理分量与纯规范分量的应用 Physical quantity = f(A phys, D pure,…)

9. Example: Consistent separation of nucleon momentum and spin van Enk and Nienhuis, J. Mod. Opt. 41:963 (1994) Chen, Lü, Sun, Wang, & T. Goldman, PRL 100:232002 (2008)

10. Gauge-invariant polarized gluon PDF and gauge-invariant gluon spin

11. Gauge invariant Chern-Simons Current Contribution to OPE and g 1 sum rule?

12. Relation between Chern-Simons Current and the spin of a gauge particle

13. The conventional gauge-invariant “quark” PDF The gauge link (Wilson line) restores gauge invariance, but also brings quark-gluon interaction, as also seen in the moment relation:

14. The novel “proper” quark PDF With a second moment:

15. The conventional gluon PDF Relates to the Poynting vector:

16. The novel gluon PDF Relates to the gauge-invariant canonical gluon momentum

17. To measure the novel quantities  The same experiments as to measure the conventional PDFs  New factorization formulae and extraction of the new PDFs  Quark and gluon orbital angular momentum can in principle be measured through generalized (off-forward) PDFs

18. Example of theoretical calculation: Quark/gluon momentum in the nucleon Gluons carry about half of the nucleon momentum in the asymptotic limit

19. 核子动量分配的 “ 新 ” 图像 “Do gluons carry half of the nucleon momentum?” X.S. Chen, W.M. Sun, X.F. Lü, F. Wang, and T. Goldman Phys. Rev. Lett., 103, 062001 (2009)

20. 核子自璇分配的 “ 新 ” 图像？ Is nucleon spin structure inconsistent with constituent quark model? Di Qing, Xiang-Song Chen, Fan Wang, (Nanjing U.). Phys.Rev.D58:114032,1998. [hep-ph/9802425] Di QingXiang-Song ChenFan WangNanjing U.

21. 季向东的 Comment 与我们的 Reply Phys.Rev.Lett.100:032002(2008) Ji’s Comment: arXiv:0810.4913 Our Reply: arXiv:0812.4336 Phys.Rev.Lett.103:062001(2009) Ji’s Comment: arXiv:0910.5022 Our Reply: arXiv:0911.0248

25. From Ji’s Comment: arXiv:0810.4913

28. From Ji’s Comment: arXiv:0910.5022

32. Our Reply: arXiv:0812.4336

33. Angular Momentum Commutators

34. Kinematic “Momentum” and Kinematic “Angular Momentum”

35. Our Reply: arXiv:0812.4336

37. Our Reply: arXiv:0911.0248

45. Thank you! 谢谢 !