February 1, 2005 Journal article Open Access

The NOAA Goes-12 Solar X-Ray Imager (SXI) 1. Instrument, Operations, and Data

Hill, S. M.; Pizzo, V. J.; Balch, C. C.; Biesecker, D. A.; Bornmann, P.; Hildner, E.; Lewis, L. D.; Grubb, R. N.; Husler, M. P.; Prendergast, K.; Vickroy, J.; Greer, S.; Defoor, T.; Wilkinson, D. C.; Hooker, R.; Mulligan, P.; Chipman, E.; Bysal, H.; Douglas, J. P.; Reynolds, R.; Davis, J. M.; Wallace, K. S.; Russell, K.; Freestone, K.; Bagdigian, D.; Page, T.; Kerns, S.; Hoffman, R.; Cauffman, S. A.; Davis, M. A.; Studer, R.; Berthiaume, F. E.; Saha, T. T.; Berthiume, G. D.; Farthing, H.; Zimmermann, F.

The Solar X-ray Imager (SXI) was launched 23 July 2001 on NOAA's GOES-12 satellite and completed post-launch testing 20 December 2001. Beginning 22 January 2003 it has provided nearly uninterrupted, full-disk, soft X-ray solar images, with a continuous frame rate significantly exceeding that for previous similar instruments. The SXI provides images with a 1 min cadence and a single-image (adjustable) dynamic range near 100. A set of metallic thin-film filters provides temperature discrimination in the 0.6 – 6.0 nm bandpass. The spatial resolution of approximately 10 arcsec FWHM is sampled with 5 arcsec pixels. Three instrument degradations have occurred since launch, two affecting entrance filters and one affecting the detector high-voltage system. This work presents the SXI instrument, its operations, and its data processing, including the impacts of the instrument degradations. A companion paper (Pizzo et al., this issue) presents SXI performance prior to an instrument degradation that occurred on 5 November 2003 and thus applies to more than 420000 soft X-ray images of the Sun.