Suppression of neutral pion production in deep-inelastic scattering off nuclei with the CLAS detector

We present the first three-fold differential measurement for neutral pion multiplicity ratios produced in semi-inclusive deep-inelastic electron scattering on carbon, iron and lead nuclei normalized to deuterium from CLAS at Jefferson Lab. We found that the neutral pion multiplicity ratio is maximally suppressed for the leading hadrons (energy fraction z approaching unity), suppression varying from 25 multiplicity ratio at low z and high p2T is observed, suggesting an interconnection between these two variables. This behavior is qualitatively similar to the previous two-fold differential measurement of charged pions by the HERMES Collaboration. However, in contrast to the published CLAS and HERMES results on charged pions, the largest enhancement was observed at high pT2 for the lightest nucleus - carbon and the lowest enhancement for the heaviest nucleus - lead. This behavior suggests a competition between partonic multiple scattering, which causes enhancement, and hadronic inelastic scattering, which causes suppression.