Eur. Phys. J. C 25, 287-289 (2002)
Forward elastic scattering of light on light,M.M. Block1 and G. Pancheri2
1 Department of Physics and Astronomy, Northwestern University, Evanston, IL 60208, USA
2 INFN-Laboratori Nazionali di Frascati, 00044 Frascati, Italy
(Received: 18 June 2002 / Published online: 9 August 2002 )
The forward elastic scattering of light on light, i.e., the reaction in the forward direction, is analyzed utilizing real analytic amplitudes. We calculate , the ratio of the real to the imaginary portion of the forward scattering amplitude, by fitting the total cross section data in the high energy region GeV, assuming a cross section that rises asymptotically as . We then compare to , the ratio of the even portions of the pp and forward scattering amplitudes, as well as to [CITE], the value for Compton scattering. Within errors, we find that the three -values in the c.m.s. energy region GeV are the same, as predicted by a factorization theorem of Block and Kaidalov [CITE].
© Società Italiana di Fisica, Springer-Verlag 2002