D..21 November, 2003 (AE Version 3.5)

• AE now requires the ``7nov2003'' or later version of the TARA package.

• A mistake¹⁹ in the computation of the KS Probability for light curves has been corrected. As shown in the left figure below the effect of the mistake is to make sources look less variable than they should, i.e. the KS probabilities previously calculated are too large. As shown in the right figure below the error is largest for sources with a small number of counts.

  A ``patch program'' that recalculates only the KS probabilities is available if you have an existing AE extraction on which you do not wish to re-run the full EXTRACT_SPECTRA stage.

  Figure 19: Error in KS Probability for Orion light curves

  

• The EXTRACT_SPECTRA TIMING stage now produces a PostScript plot of event arrival times and energies--see §7.11.

• The way background regions are used to select the events that form the background spectrum has been revised to improve the accuracy of the background scaling, particularly for regions that are small compared to the pixel size of the exposure map. See note in §7.13.

• The keyword MIN_EXPOSURE_RATIO has been added to the EXTRACT_BACKGROUNDS stage to improve observer's control over the size of background regions.