Theory

Quark distribution Functions

Polarized

The inclusive double polarization asymmetries [math]\displaystyle{ A_N }[/math] can be written in terms of polarized [math]\displaystyle{ \triangle q_v (x) }[/math] and unpolarized [math]\displaystyle{ q_v (x) }[/math] valence quark distributions,

[math]\displaystyle{ A_{1,p} }[/math] = [math]\displaystyle{ 4\triangle u_v (x) }[/math] + [math]\displaystyle{ \triangle d_v (x) }[/math]

[math]\displaystyle{ 4 u_v (x) }[/math] + [math]\displaystyle{ d_v (x) }[/math]

[math]\displaystyle{ \frac {<math>4\triangle u_v (x) }[/math] + [math]\displaystyle{ \triangle d_v (x) }[/math]} {[math]\displaystyle{ 4 u_v (x) }[/math] + [math]\displaystyle{ d_v (x) }[/math]} </math>