ENERGY-DEPENDENCE OF COLOR TRANSPARENCY

A quantum-mechanical approach is used to study high-momentum-transfer reactions in which a nucleon is knocked out of a target nucleus. It is found that the nuclear interactions of the wave packet produced in such a hard interaction may cancel, so that the nuclear medium is transparent. Expressions for the effective wave-packet-nucleon interaction and the corresponding distorted waves are presented. An analysis of existing (p,pp) data at beam momenta from about 5 to 12 GeV/c suggests that only the nucleon and Roper resonance components of the wave packet contribute to the scattering amplitude. The (p,pp) data and our theory imply that color-transparency effects in the (e,e'p) reaction may be significant at relatively low-momentum transfers of Q2 almost-equal-to 3-6 GeV2.