Transcript 偏極ビーム・標的によるDrell-Yan過程でのスピン観測量と核子構造

偏極ビーム・標的による
Drell-Yan過程での
スピン観測量と核子構造
田中和廣 (順天堂大)

X
D IS :

 p   X
S ID IS :
 p    X
The first global fit at LO
Anselmino et al., PRD75 (’07) 054032
arXiv: 0807.0173
T q  x   0
n o d ata fo r x  0 .4
Drell-Yan: p   p  
AT T 


d

d

 d

 d



 X
Q
2
2
2
2
2
2
e q   T q ( x1 , Q )  T q ( x 2 , Q )   T q ( x1 , Q )  T q ( x 2 , Q )  
q

2
2
2
2
2
e q  q ( x1 , Q ) q ( x 2 , Q )  q ( x1 , Q ) q ( x 2 , Q )  
q

p  p


AT T 
J-PARC:



S  10 Ge V , x 1,2  0. 1
 X
2
2
2
2
2
e q   T q ( x1 , Q )  T q ( x 2 , Q )   T q ( x1 , Q )  T q ( x 2 , Q )  
q

q
2
2
2
2
2
e q  q ( x1 , Q ) q ( x 2 , Q )  q ( x1 , Q ) q ( x 2 , Q )  
GSI:
S
6 G e V , x 1,2  0. 2
Kawamura, Kodaira, Tanaka,
NPB777 (’07) 203
resummation
PTP 118 (’07) 581
PLB662 (’08) 139
2
QT
Q ,y
@ J-PARC
@ J-PARC
Q  2 G eV , y= 0
@ GSI
S  14.5 G eV , Q  4 G eV , y=0
@ RHIC
S  500 G eV , y= 2
AL T 


q
d

d

 d

 d

2
2
q
2
q
2
2
e q   q ( x 1 , Q ) x 2 g T ( x 2 , Q )  x 1 h L ( x 1 , Q )  T q ( x 2 , Q )   x 1  x 2  

q
2
2
2
e q  q ( x 1 , Q ) q ( x 2 , Q )   x 1  x 2  
h L , gT : twist-3 parton distri butions
1
2
hL (x , Q )  2 x  dy
q
2
 T q(y, Q )
y
x
q
gT ( x , Q ) 
2

1
x
2
q(y, Q )
 " genuine tw ist-3 "
2
dy
y
 " genuine tw ist-3 "
Wandzura-Wilczek part
@J-PARC
S  10 GeV
(from presentation by S. Yoshida)
x F  x1  x 2
@GSI
S  6.7 GeV
(Koike, Tanaka, Yoshida, arXiv:0805.2289)
Summary
Drell-Yan processes using
polarized beam and target
at J-PARC
A LL
q (x )
ATT
 T q ( x ),  T q ( x )
A LT
q q g three-body correlat ion
including large x region
Clean! unique!!