Cosmic Ray Electron Synchrotron Telescope (CREST) status report

The CREST instrument aims to detect cosmic electrons beyond a few TeV, which would likely originate in the local Galactic neighborhood, within a kpc or so, owing to their rapid energy loss rates during propagation. Only a few candidate acceleration sites exist within this horizon, such as Vela, Monogem, and the Cygnus Loop remnants, and thus multi-TeV electrons are a useful marker of the nearby high energy universe. CREST detects electrons through their geosynchrotron x-ray emissions in the South polar regions of the Earth. The signature is a stream of x-ray photons emitted in the plane of electron travel, intersecting the plane of a horizontal detector array; the net effect is a co-linear arrangement of x-ray hits coincident in time. To this end an array of 1024 BaF₂ crystal detectors was built, surrounded by veto plastic scintillators to guard against chance alignments of charged particles in air showers. This instrument was successfully flown on a high-altitude balloon for 10 days in Antarctica, starting December 25, 2011, and recovered in February 2012. The status of the analysis of the data from this flight is presented.