About RXTE

The HEXTE

The HEXTE consists of two clusters each containing four phoswich scintillation detectors. Each cluster can ``rock'' (beamswitch) along mutually orthogonal directions to provide background measurements 1.5 or 3.0 degrees away from the source every 16 to 128 s. Automatic gain control is provided by using a 241Am radioactive source mounted in each detector's field of view. The HEXTE's basic properties are:

  • Energy range: 15 - 250 keV
  • Energy resolution: 15% at 60 keV
  • Time sampling: 8 microsecond
  • Field of view: 1 degree FWHM
  • Detectors: 2 clusters of 4 NaI/CsI scintillation counters
  • Collecting area: 2 times 800 cm^2
  • Sensitivity: 1 Crab = 360 count/s per HEXTE cluster
  • Background: 50 count/s per HEXTE cluster

Events detected by HEXTE will be processed on board by its own data system before insertion into the telemetry stream at an average data rate of 5 kbit/s. Data products include event mode, binned spectra and light curves, and a burst-triggered event buffer.

The HEXTE was designed and built by the Center for Astrophysics & Space Sciences (CASS) at the University of California, San Diego. For more information, see the HEXTE home page at UCSD.

The HEXTE principal investigator is Dr. Richard E. Rothschild.

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