Adependence of photoproduced dijets

We present a measurement of the A dependence of ${\mathit{k}}_{\mathit{T}\mathrm{\phi }}$, the out-of-plane component of the dijet transverse momentum, in dijet events produced with a real photon beam. We also present the same measurement for dijets produced from pion-nucleus collisions in our detector. Both data sets are taken at a mean √s of 21 GeV in the ${\mathit{p}}_{\mathit{T}}$ range 3–7 GeV/c. A clear A dependence of comparable magnitude is seen in both processes. The energy dependence of the nuclear behavior is also extracted.