QUANTUM-MECHANICAL EQUIVALENT-PHOTON SPECTRUM FOR HEAVY-ION PHYSICS -COMMENT

We critically discuss the recently developed quantum-mechanical equiva lent photon spectrum by Benesh et al. [Phys. Rev. C 54, 1404 (1996)]. We point out that the key point, the strong absorption in heavy ion co llisions, is not treated adequately. Conclusions drawn from such a spe ctrum are invalid. Equivalent-photon spectra appropriate for heavy ion s have been given before in quantal, as well as semiclassical versions , and were found to be very satisfactory.