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