Radiative corrections to the photon + 1 jet rate at LEP

Abstract We present the results of a calculation of the rate for the annihilation of an e + e − pair into a jet containing an energetic photon and a single further jet at order αα s . By comparing these results with the existing data on the photon + 1 jet rate from the ALEPH Collaboration, we make a first determination of the process independent quark-to-photon fragmentation function D q → γ ( z , μ F ) at order αα s . We also compare our prediction for the inclusive photon energy spectrum with the recent OPAL measurement.