Breakdown of Conventional Factorization for Isolated Photon Cross Sections
Breakdown of Conventional Factorization for Isolated Photon Cross Sections
Using ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}\ensuremath{\gamma}+X$ as an example, we show that the conventional factorization theorem in perturbative quantum chromodynamics breaks down for isolated photon cross sections in a well-defined part of phase space. Implications and physical consequences are discussed.