Transverse momentum spectra from PHOBOS at RHIC

The PHOBOS experiment has obtained transverse momentum distributions for charged hadrons and identified hadrons in nuclear collisions at RHIC. The spectra were studied as a function of system size in d+Au and Au+Au collisions at 200 GeV/nucleon, and also as a function of collision energy in Au+Au. In this talk, a systematic survey of recent data will be compared with predictions of various models, with particular emphasis on the intermediate and high $p_T$ regions.