Production of hadrons at large transverse momentum at 200, 300, and 400 GeV

We have measured, as a function of transverse momentum (p_), the invariant cross section Ed{d^3p} for the production of ^, K^, p, p, d, and d in proton collisions with a tungsten (W) target at incident proton energies of 200, 300, and 400 GeV. The measurements were made in the region of 90^ in the c. m. system of the incident proton and a single nucleon at rest. Measurements were also made with 300-GeV protons incident on Be, Ti, and W targets of equal interaction length. These p-nucleus measurements, which show a strong dependence on atomic number at high p_, were used to extract effective proton-nucleon cross sections by extrapolation to atomic number unity. At large values of the scaling variable x_=2p_{}s, where s is the square of the c. m. energy, the pion data are found to be well represented by the expression (s) ^-ne^-{ax_}, with n=11. 00. 4 and a=36. 00. 4. x_<0. 35, where similar measurements have been made at the CERN ISR, our data are in good agreement with the ISR data.