STIS Echelle Blaze Shift Correction
نویسندگان
چکیده
Planned offsets of the STIS Mode Select Mechanism (MSM) result in changes to the nominal calibration curves, particularly noticeable in the echelle modes. The spectral wave calibration exposures (wavecals) obtained with each observation can be used to predict a simple, linear offset of the nominal calibration curve to be used for each MSM shift. In addition, a time dependent variation has been detected which is attributed to small changes in the grating itself. An algorithm has been developed which applies the offsets necessary to correct both the time dependent and MSM shift effects for the echelle modes.
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تاریخ انتشار 2003