Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Q/sup 2/ dependence in exclusive two photon reactions

Thesis/Dissertation ·
OSTI ID:7161925
Calculations of the cross sections for ..gamma../sup */..gamma../sup */ ..-->.. m(antim), two photon production of meson-antimeson, and ..gamma../sup */..gamma../sup */ ..-->.. B(anti-B), two photon production of baryon-antibaryon, are presented for the case in which one or both of the photon is off-shell. The results are shown to be in agreement with the Q/sup 2/ ..-->.. 0 limit for ..gamma gamma.. ..-->.. m(anti-m) calculated by Brodsky and Lepage and for ..gamma gamma.. ..-->.. B(anti-B) calculated by Farrar, Maina, and Neri. It is further shown that Q/sup 2/ dependence, (Q/sup 2/ = -(four momentum of the photon)/sup 2/), provides tests of the applicability and consistency of perturbative QCD and the factorization formalism. In particular, the Q/sup 2/ dependence is sensitive to the choice of distribution amplitude; thus the Chernyak and Zhitnitsy distribution amplitude that is best for fitting the proton form factor at present experimental energies can be tested with an independent process.
Research Organization:
California Univ., Davis (USA)
OSTI ID:
7161925
Country of Publication:
United States
Language:
English