Theory

Quark distribution Functions

Polarized

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

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

[math]4 u_v (x)[/math] + [math]d_v (x)[/math]

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