TENSOR ANALYZING POWERS IN THE REACTIONS P(D,P)D AND P(D,P)PN AT ZEROANGLE FOR INCIDENT-DEUTERON MOMENTA BETWEEN 3.5 AND 6.5 GEV C/

The tensor analyzing powers T-20 in the reactions p(d, p)d and p(d, p) pn at zero angle (theta(c.m.s.) = 180 degrees) are measured for incide nt-deuteron momenta between 3.5 and 6.5 GeV/c. For each of the reactio ns, T-20 remains negative up to the incident momentum of 6.5 GeV (the corresponding value of the internal nucleon momentum in the deuteron a s estimated in the light-front frame is k similar or equal to 0.85 GeV /c). This behavior of T-20 is at odds with the predictions of the stan dard one-nucleon-exchange model. A new structure at k similar or equal to 0.65 GeV/c is revealed in the k dependence of T-20 for the reactio n p(d, p)d. The quantity T-20 for the pion-free breakup of a deuteron is measured for the first time. For a fixed value of k, it is found to differ from the T-20 values either for elastic backscattering or for the kinematical region of deuteron breakup where pion formation is not forbidden. The differential cross section for the reaction p(d, p)pn reveals a quasiresonance enhancement near the kinematical boundary of the secondary-proton spectrum. New measurements of T-20 for the proces s p(d, d')X in the M-X region between 1.46 and 1.62 GeV/c(2) are repor ted.