A change of target density at constant target volume corresponds to a change in n(j) which can in general be different for each run i: n(j)i.
In this case the averaging of the polarizations gets affected too and the formalism looks like the following:
Averaged n(j)i:
Averaged polarizations:
Beam-target asymmetry (eq. 2) with averaged n(j)iaccording to eq. 13 and averaged polarizations according to eq. 14
to 18: