About 45000 interactions of antiprotons of kinetic energy between 57 and 170 MeV have been measured in a deuterium bubble chamber. Total and annihilation cross-sections have been determined at 9 values of the antiproton energy together with the differential crosssection dσ/dt for scattering events. In spite of the peculiar behaviour of the deuteron target at these low energies a reliable measure of the antiproton-neutron annihilation cross-section has been obtained.
INELASTIC (ANNILATION + CHARGE EXCHANGE), SCATTERING (ELASTIC + INELASTIC) AND TOTAL CROSS SECTIONS. AUTHORS ALSO GIVE TOPOLOGICAL DECOMPOSITION OF THESE CROSS SECTIONS.
SCATTERED ANTIPROTON ANGULAR DISTRIBUTION. THE OPTICAL POINT AT T=0 IS CALCULATED FROM THE TOTAL CROSS SECTION. SEPARATION INTO SCATTERING ON PROTONS AND ON NEUTRONS IS IMPOSSIBLE.
Based on 150 000 photographs taken at the ZGS with the 30 inch deuterium-filled chamber we present an analysis of the elastic p d scattering reaction. Due to unrecoreded small deuteron recoils we were only able to measure the elastic cross section in the four-momentum region | t | > 0.03 (GeV/ c ) 2 . Extrapolation towards small | t | by two different methods gave us two compatible estimates of the total elastic cross section. The differential cross section was analyzed by means of the Glauber formalism both with and without the effects due to the D-wave part of the deuteron wave function. The differential cross sections of np at 5.4 GeV/ c and pn deduced from our data were compared and exhibit a crossover phenomenon.
CALCULATED USING TOTAL ELASTIC SIG(-T > 0.03 GEV**2) = 7.2 +- 0.4. THE SMALL ANGLE SCATTERING APPROXIMATION HOLDS: D(SIG)/DOMEGA(RF=LAB) = (P**2/PI)*D(SIG)/DT.
INTEGRATED CROSS SECTION USING EITHER EXPONENTIAL EXTRAPOLATION OR GLAUBER MODEL FIT FOR -T < 0.03 GEV**2.
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