PHEBUS is a Payload for High Energy BUrst Spectroscopy onboard the GRANAT observatory. There are 6 crystals of bismuth germanate 78 mm in diameter and 120 mm long each which are placed on different sides of the spacecraft. These detectors work in the hardest energy range among all the instruments of GRANAT - from ~0.1 MeV up to ~100 MeV (SIGMA telescope is only sensitive up to 1.3 MeV). However, PHEBUS does not provide the information on the direction of incident photons and its possibility to localize the sources of gamma-ray bursts is much lower than that of telescopes with coded mask, devices with rotating collimators (such as WATCH) and BATSE experiment. Instead PHEBUS supercedes all of these devices in its spectroscopic possibilities. None of the instruments above has an energy range which covers three decades of wavelenghts. That allows for PHEBUS to investigate spectral behaviour of dozens of GRB's as well as their evolution with time.

Three brightest bursts observed by PHEBUS


Back to my Home Page