BATSE Octahedron

What does an octahedron have to do with BATSE?

The octahedron represents the Large Area Detector (LAD) geometry when BATSE is installed on the Compton Gamma-Ray Observatory.

The LADs on each of the eight BATSE modules are oriented so that when the module is in a horizontal position, the face of each LAD is at an angle of approximately 54.7 degrees with the vertical direction. This angle is required so that the planes of the LADs intersect to form a regular right octahedron. This configuration was chosen so that each gamma-ray burst would be observed by four detectors simultaneously. There is a special case in which a burst would be observed by only two detectors - can you think of when this would occur?

A burst that is directly in front of the midpoint of the edge shared by two detectors will be observed by only those two detectors. This is a relatively rare occurrence for BATSE.

Would you like some more information on the BATSE instrument?

Please return to the BATSE Home Page or the Gamma Ray Astrophysics Home Page.

Author	Robert S. Mallozzi
Responsible Manager	Steve Elrod
Site Curator	Valerie Connaughton