  Measurement of jet fragmentation property in p + p collisions provides a
crucial baseline for the study of a possible, modified fragmentation behavior
at the presence of the quark-gluon plasma. We describe the first measurement of
jet fragmentation functions in sqrt(s) = 200 GeV p + p collisions at RHIC. This
is facilitated by extending the linear least square unfolding technique
employed by high energy and nuclear experiments to multidimensional spectra,
which allows us to correct the inefficiencies in the jet energy response
encountered at detectors such as PHENIX.
