Large Polarization Asymmetries in Nucleon-Nucleon Scattering

  • A. O. Barut
Part of the Ettore Majorana International Science Series book series (EMISS, volume 31)


When planning antiproton polarization experiments, as discussed at this Meeting, it may be good to remember the large polarization effects discovered in recent years in proton-proton and neutron-protron experiments1. Similar effects should be expected in the antiproton case. The large spin effects came unexpectedly, not only because one generally thought the spin effects in strong interactions to be small, but also the pertur-bative QCD predicted no such spin asymmetries. This is due to a theorem that for Yμ-type interactions at higher energies the helicity is conserved for arbitrary tree-Feynman diagrams2. It was no surprise to other models in which one expected large spin (rather magnetic moment) effects at short distances3. At any rate these experiments test more crucially the per-turbative QCD than unpolarized experiments, and actually show that PQCD is not sufficient to understand these phenomena.


Anomalous Magnetic Moment Large Spin Large Polarization Spin Asymmetry Elementary Particle Physics 


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Copyright information

© Plenum Press, New York 1987

Authors and Affiliations

  • A. O. Barut
    • 1
  1. 1.International Centre for Theoretical PhysicsTriesteItaly

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