  Hadron multiplicities in semi-inclusive deep-inelastic scattering were
measured on neon, krypton and xenon targets relative to deuterium at an
electron(positron)-beam energy of 27.6 GeV at HERMES. These ratios were
determined as a function of the virtual-photon energy nu, its virtuality Q2,
the fractional hadron energy z and the transverse hadron momentum with respect
to the virtual-photon direction pt . Dependences were analysed separately for
positively and negatively charged pions and kaons as well as protons and
antiprotons in a two-dimensional representation. Compared to the
one-dimensional dependences, some new features were observed. In particular,
when z > 0.4 positive kaons do not show the strong monotonic rise of the
multiplicity ratio with nu as exhibited by pions and negative kaons. Protons
were found to behave very differently from the other hadrons.
