Our paper on first event activity dependent jet measurements in pPb collisions is submitted to arXiv:1401.4433. The dijet transverse momentum ratio is found to be independent of event activity in pPb collisions. This confirms that the dijet transverse momentum imbalance enhancement in central PbPb collisions is not originating from initial-state effects. It also shows that any final state effect on jets in pPb collisions is small, justifying the usefulness of jets in studying initial state effects.
Initial state effects due to nuclear parton distribution functions(nPDFs) are quantified by the measurement of dijet pseudorapidity in minimum bias events. The measurement is agreement with EPS09 nPDF, while it disfavors the calculation with CT10 proton PDF. The observation of a large modification in dijet pseudorapidity and the shift in its mean towards the lead beam direction as a function of event activity sets a new puzzle for the field. Some clues to understand the shift are included in the paper by the measurement of dijet pseudorapidity as a function of activity in the lead direction for fixed the activity in the proton direction.