Charge Diffusion Variations in Pan-STARRS1 CCDs

Magnier, E.A.; Tonry, J.L.; Finkbeiner, D.; Schlafly, E.; Burgett, W.S.; Chambers, K.C.; Flewelling, H.A.; Hodapp, K.W.; Kaiser, N.; R.-p., Kudritzki; Metcalfe, N.; Wainscoat, R.J.; Waters, C.Z.

Abstract

Thick back-illuminated deep-depletion CCDs have superior quantum efficiency over previous generations of thinned and traditional thick CCDs. As a result, they are being used for wide-field imaging cameras in several major projects. We use observations from the Pan-STARRS 3π survey to characterize the behavior of the deep-depletion devices used in the Pan-STARRS 1 Gigapixel Camera. We have identified systematic spatial variations in the photometric measurements and stellar profiles that are similar in pattern to the so-called "tree rings" identified in devices used by other wide-field cameras (e.g., DECam and Hypersuprime Camera). The tree-ring features identified in these other cameras result from lateral electric fields that displace the electrons as they are transported in the silicon to the pixel location. In contrast, we show that the photometric and morphological modifications observed in the GPC1 detectors are caused by variations in the vertical charge transportation rate and resulting charge diffusion variations.

Citation

Magnier, E., Tonry, J., Finkbeiner, D., Schlafly, E., Burgett, W., Chambers, K., …Waters, C. (2018). Charge Diffusion Variations in Pan-STARRS1 CCDs. Publications of the Astronomical Society of the Pacific, 130(988), Article 065002. https://doi.org/10.1088/1538-3873/aaaad8

• Journal Article Type: Article
• Acceptance Date: Jan 25, 2018
• Online Publication Date: Apr 16, 2018
• Publication Date: Apr 16, 2018
• Deposit Date: May 16, 2018
• Publicly Available Date: May 16, 2018
• Journal: Publications of the Astronomical Society of the Pacific
• Print ISSN: 0004-6280
• Publisher: Astronomical Society of the Pacific
• Peer Reviewed: Peer Reviewed
• Volume: 130
• Issue: 988
• Article Number: 065002
• DOI: https://doi.org/10.1088/1538-3873/aaaad8
• Public URL: https://durham-repository.worktribe.com/output/1330723