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Last modified: 26 October 2007
Hardcopy (PDF): A4 | Letter

What does this warning mean?

*** WARNING: The ARF was computed to be zero at all the specified energies.
             This is probably due to an incorrect source position

There are some other cases where this is expected to happens - e.g., a mask truncates the order or the chip was turned off.

However, if you get this error for all orders and chips, then something is wrong. There are a few possible situations:

  1. An incorrect source position was input to the sourcepixelx and sourcepixely parameters. Confirm that the source position is correct, and re-run the tool if it's not.

  2. You are attempting to create a gARF for an order that does not fall on that plate, e.g. a positive order on HRC-S3. Refer to the Analysis Guide for Chandra High Resolution Spectroscopy for more information.

If neither of these seems to fix the problem, contact the Helpdesk for assistance.



Hardcopy (PDF): A4 | Letter
Last modified: 26 October 2007


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