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arXiv · 2608.10167

CCD Rotation Rates From Regular Dispersion Solution Monitoring

Matilde Mingozzi·Matthew Siebert
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Abstract

It has been previously studied that the STIS CCD exhibits a slow rotation, evident from changes in spectral traces and flat-field evolution. In this Instrument Science Report, we present an independent spectroscopic analysis of the CCD rotation angle and a comparison with previous studies. We describe the methodology used to derive rotation angles and rates across different gratings and central wavelengths, and report the corresponding median rotation rates over time. The results are broadly consistent within uncertainties with earlier measurements, indicating the CCD rotation has the same impact on all the CCD gratings. We also discuss key assumptions limiting our analysis. These findings contribute to the ongoing monitoring of STIS CCD rotation and its implications for calibration accuracy.

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Matilde Mingozzi, Matthew Siebert. 2026-08-10. CCD Rotation Rates From Regular Dispersion Solution Monitoring. https://arxiv.org/abs/2608.10167

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