Background Region Error

April 20, 2001

Image of Level 2 event file (which is truncated by an incorrect parameter value in tg_create_mask) with spectral and background extraction regions superposed. Data are cut off at tg_d = +/- 2.5 mm, resulting in incomplete background accumulation. (Figure by V. Kashyap.) This problem was corrected in the July 2 2001 DS 6.1.0 software release by increasing the default value of tg_create_mask.width_factor_letg from 20 to 40.

Extracted background from HZ43 (obsid 59), positive order, outer HRC-S segment. As can be seen, the background flattens out at around 120 Angstroms, although it should continue to increase. The effect of PI filtering is also shown. (Figure by D. Pease.)

Last modified: 08/09/07

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