Implications of Regge behavior for processes involving photons

Henry D.I. Abarbanel*, S. Nussinov

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review


Properties of the crossing matrix for helicity amplitudes are enumerated and then exploited in a simple Regge-pole model of photon-hadron interactions. We find that: (1) The vacuum or Pomeranchuk trajectory is absent in forward Compton scattering of real photons on nucleons or pions. Thus the total nuclear cross section for photons or nucleons should vanish asymptotically. (2) The amplitudes entering the forward spin-flip Compton scattering of virtual photons on protons, which are crucial in the proton structure contributions to the ground-state hyperfine splitting (hfs) in hydrogen, may be chosen so that they do not require a subtraction when writing dispersion relations for them in the energy variable. One must look elsewhere than to the high-energy behavior of the amplitudes for the erasure of the discrepancy between theory and experiment on the hfs. (3) In forward photoproduction of vector mesons on protons, the polarization of the mesons should be predominantly longitudinal at "high energy." (4) In the differential cross section ddt for photoproduction of neutral pions, there should be a dip at t-0.5 BeV2 because of a nonsense zero in all crossed-channel helicity amplitudes.

Original languageEnglish
Pages (from-to)1462-1466
Number of pages5
JournalPhysical Review
Issue number5
StatePublished - 1967
Externally publishedYes


FundersFunder number
U. S. Air Force Office of Research, Air Research and Development CommandAF 49(638)-1545


    Dive into the research topics of 'Implications of Regge behavior for processes involving photons'. Together they form a unique fingerprint.

    Cite this