Position-refinement methods have been developed and arecurrently used in operations at the Spitzer Science Center to optimallyregister infrared astronomical images taken by the Infrared Array Cam-era (IRAC), one of the three science instruments onboard the SpitzerSpace Telescope. The methods routinely involve frame-to-frame opti-mal matching of point sources in overlapping images and point-sourcematching to absolute-astrornetric 2MASS-catalog sources. A recently-studied case consists of Spitzer observation campaign IRAC006800, inwhich 44,173 raw images were acquired in all four IRAC channels (corre-sponding to infrared spectral bands centered at 3.6, 4.5, 5.8, and 8.0 ,um).An analysis demonstrated that, for images in the two shortest wavelengthbands, the average radial separations between image sources and their ab-solute matched counterparts are reduced from R-_,'0.34 arcseconds to arcseconds as a result of position-refinement processing. There are alsoimprovements for images in the two longer wavelength bands, althoughnot by as much (only a factor of reduction) because the matchedstars are fainter and the image data are noisier. An additional capabilitythat will soon go online, called the super-boresight pipeline, is the simul-taneous refinement of IRAC images from all four of its wavelength-bandchannels. This allows the pointing information gained from the shorterwavelength channels to benefit those at longer wavelengths.
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