Speaker
Benjamin Bannier
Description
Photons are produced at all stages of a nuclear collision. Because of their
extremely small interaction rate with the hadronic medium any information they
carry about their production environment is accessible nearly undistorted in
their final state. Photons are produced in hadronic decays, hard scatterings
of initial state partrons, jet-photon conversions and from thermal radiation
of the medium. At the lowest photon momenta hadronic decays and thermal
production are the dominant sources. Any direct measurement of low-momentum
photons is challenging in an electro-magnetic calorimeter due to large
backgrounds and measurement uncertainties from hadron contamination in this
energy regime. We will present a method for measuring real photons with
external conversions with the PHENIX detector that allows measurements of
these photons with improved systematic uncertainties.
