Enhancement ofγ-Ray Absorption in the Radiation Field of a High-Power Laser

This paper reports an analytic estimate of the cross section for the absorption of a $\gamma$-ray photon when the nuclear recoil is compensated by the simultaneous absorption of an optical photon from the radiation field of a high-power laser. A multiphonon transition model is developed and cross sections of the order of 1 ${\mathrm{fm}}^2$ are obtained when nearly resonant intermediate states of nuclear excitation are assumed to lie within a few tens of eV of the transition energy.