New formalism for the nuclear Drell-Yan process

摘要: Abstract A more systematic derivation of the new formalism for Drell-Yan processes on nuclear targets is developed by expanding tensor in terms nucleon tensor. As explained previously, which compatible with factorization theorem very different from commonly used procedure two aspects. First, not target-quark distribution function alone, but product projectile and functions convoluted nucleon-momentum function. Second, since cross sections are expressed centre-of-mass system, transformation projectile-nucleus to-nucleon systems introduces an additional effect through kinematical factors inherent The formulae agree those obtained constituent interchange model. Using formalism, investigated proton scattering off a 184 W target found stronger than naive expectation based free-nucleon would have indicated. difference conventional result dependent both heavy-lepton mass Feynman variable.