New explorations of femtoscopy for ultra-peripheral collision studies

Femtoscopy has the potential to unravel the spatiotemporal structure of ultra-peripheral collisions (UPCs), but complex sources and processes produce complicated correlation signals which must be disentangled. In previous work, source functions appropriate for UPCs were constructed. A Correlation Analysis Tool using Schroedinger’s equation (CATS) generated two-vector meson correlation functions sensitive to nuclear gluon structure and impact parameter distributions. Those studies are now extended using photonuclear events simulated with the STARlight event generator.

Event simulations permit an exploration of relationships between kinematic quantities, UPC event processes and correlation functions, including non-femtoscopic backgrounds. Understanding such backgrounds is essential for interpreting any signals due to Bose-Einstein enhancement. Studies of these relationships will be presented.

New predictions with realistic impact parameter distributions in different nuclear breakup scenarios will also be presented. Extension to two-pion correlation functions in these events might also be discussed.