John Russell

Line reversal in baryon exchange processes

We present differential cross sections at 6 GeV/c for π− and p‐induced baryon exchange reactions. These data are used to test line‐reversal symmetry in baryon exchange. Nearly identical triggers were used for each reaction, so that systematic errors in the line reversal tests are small.

Single spin asymmetry in large pt inclusive π+ and π− production from p↑p interactions

Data are presented for the left‐right asymmetry in inclusively produced π+ and π− with a transverse polarized proton beam on an unpolarized LH2 target. Above pt of 1 GeV/c, and large asymmetry is seen for the π+ and little asymmetry is seen for the π−.

Probing perturbative QCD and nuclei with large angle elastic scattering

The experiment reported here (AGS Exp. 834) seems particularly appropriate for a conference on the intersections of particles and nuclear physics. We have performed a new probe of aspects of perturbative QCD and the time evolution of hadrons inside nuclei. Simultaneously, we determined the momentum dependence of nuclear spectral functions. That is we measured the momentum distribution of nucleons inside nuclei with a sensitivity to components well beyond the edge of the normal Fermi distribution. (AIP)

Measurement of the line-reversed reactions p-barp. -->. pi. /sup -/rho/sup -/ and. pi. /sup -/p. -->. prho/sup -/ at 6 GeV/c

Differential cross sections and density-matrix elements in rho/sup -/ decay have been measured at 6 GeV/c for p-barp ..-->.. ..pi../sup +/rho/sup -/ and its line-reversed partner ..pi../sup -/p ..-->.. prho/sup -/ in the range t/sub min/ > t > - 1.5 (GeV/c)/sup 2/. The reactions satisfy line-reversal symmetry and the rho/sup -/ decay is consistent with isotropy for -t or = 0.5(GeV/c)/sup 2/, the differential cross sections show a weaker t dependence, and the decays become anisotropic.