Phoswich Detector Assembly
General Principles
Each detector assembly in the HEXTE cluster utilizes two types of detectors.
The primary function of the instrument (to measure high energy cosmic
x-rays) is accomplished via thallium-doped sodium iodide (NaI(Tl))
scintillation crystals which viewed by photomultiplier tubes. In addition,
particle detectors are used to reject contaminating events from cosmic ray
interactions, and to provide a signal from the calibration source which is
used for automatic gain control.
Each detector has a net open area of about 225 cm2
and covers the energy range 15-250 keV, with an intrinsic spectral resolution
better than 9 keV at 60 keV. The phoswich detector architecture employed
ensures a low background through the efficient shielding of the primary
NaI detector crystal by the CsI shield/light guide crystal.
Collimators
- Gain
Control Detectors - Phototubes
- Phoswich
- Magnetic
Shielding
HEXTE
Cluster