In-flight Calibration of CREST

The Cosmic Ray Electron Synchrotron Telescope (CREST) is a balloon-borne experiment that seeks to measure the cosmic ray electron spectrum. The spatial distribution of sources, such as supernova, is expected to cause a dramatic departure from the power law energy spectrum. CREST identifies electrons from the linear train of synchrotron radiation produced by the electrons motion in the Earth's magnetic field. A scaled prototype is scheduled to fly the summer of 2005 as a proof-of-concept flight. The details of the implementation of the pulser system, which allows for in-flight calibration of the photodetector array, will be shown.