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Last modified: 15 December 2008
Hardcopy (PDF): A4 | Letter

ACIS Background


The ACIS background consists of a relatively soft Cosmic X-ray Background contribution and cosmic ray-induced events with a hard spectrum. These components are changing very slowly with time and can be predicted well (although they cannot be separated at present). There is an occasional strong third component producing background flares.

There are many resources on the CXC website about the ACIS background and how it should be included in the analysis:



Hardcopy (PDF): A4 | Letter
Last modified: 15 December 2008


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