'Colliding beam' enhancement mechanism of deuteron-deuteron fusion reactions in matter

We consider a 'ping-pong' mechanism of enhancement for fusion reactions bet ween a low-energy external deuteron beam and the deuterons in a condensed m atter or molecular target. This would effectively convert the fixed target process into a colliding beam reaction. In a limiting case this reduces the negative penetrability exponent by a factor of root2. We discuss a contrib ution given by zero-point motion of a bound target deuteron and effects of acceleration of a target deuteron by the Coulomb field of a projectile. The proposed mechanism is expected to be efficient in compounds with target de uterons localized in the vicinity of heavy atoms.