Double spin asymmetry

I measure a double spin asymmetry defined as follows

Equation 1

where N-(anti)parallel indicates yields measured in one half of the detector when the beam polarisations are aligned (opposite) and P₁ and P₂ are the polarisations of the beams. Accounting for the relative luminosity, these yields are given by

Equation 2

Equation 2

where the arrows again indicate beam polarisations. Figures one and two show the fill-by-fill measurement of A_TT, corrected by the beam polarisation, summed over all p_T.

Figure 1: K0S ATT fill-by-fill

Figure 2: Λ ATT fill-by-fill