1. 摂動ＱＣＤに基づくシングルスピン非対称研究の現状
ーツイスト３機構の立場からー
小池裕司（新潟大学）
第１回高エネルギーQCD・核子構造勉強会
2014年2月4日＠理研，和光

4. FNAL-E704
P.L. B264 (’91) 462
P.L. B261 (’91) 201

20. ★ RHIC-STAR (‘04) ★ RHIC-BRAHMS (‘07)
First, we have to confirm the validity of the perturbative calculation .

21. - Graphical representation of the 1st , 2nd and 3rd terms :
Qiu, Sterman (‘99), Kouvaris
et.al.(‘06),YK-Tomita(‘09),
Kanazawa-YK(‘10)
Beppu,YK,Kanazawa,Yoshida(‘13)
Kang, Yuan, Zhou (‘10),
Metz, Pitonyak,(‘12)
Kanazawa, Koike (‘00)
⇒ The last term can be ignored.
- Graphical representation of the 1st , 2nd and 3rd terms :
In this process, there are three nonperturbative functions.
So, the twist-3 contributions to the spin dependent cross-section are obtaind by replacing a twist-2 distribution or fragmentation function by corresponding twist-3 distribution of fragmentation functions.
So, two resaonable contribution to the SSA.
The calculation is implete.

22. - Reasonable description of SSA for pions and kaons with this formula:
Koike-Tomita (2009)
Kouvaris-Qiu-Vogelsang-Yuan (2006)
- Reasonable description of SSA for pions and kaons with this formula:
KK-Koike (2010)

23. PT dependence is well reproduced :
★ STAR (2008)
PT dependence is well reproduced : ⇒

46. ★ Decomposition of the asymmetries into each fragmentation channel
- The difference comes from the strange components.