Isolated Prompt Photon Cross Sections
  We show that the conventionally defined partonic cross section for the production of isolated prompt photons is not an infrared safe quantity. We work out the case of $e^+e^-\to\gamma + X$, and discuss implications for hadron reactions. 
Edmond L. Berger (Argonne), Xiaofeng Guo and Jianwei Qiu (Iowa State)