NIRCam Ginkgo Leaf

This wispy artifact shaped like a ginkgo leaf was observed in long wavelength images in module A (detector A5). It was produced by scattered light from a star to the left (+V2) of the detector and ~24.5" below (-V3) the top edge. So far it has been seen in one observing program. Dithers should be sufficient to mitigate this rarely observed feature.

Figure 1. NIRCam ginkgo leaf

The wispy ginkgo leaf artifact in the dashed box was observed in NIRCam commissioning program 1067, observation 453 in detector A5. It appeared in all 10 images during a scan: as the star moved further off the detector (to the left), the glint moved further onto the detector (to the right). The star was off the left side (+V2) of detector A5 and ~24.5" below the top edge (in V3). A similar scan of module B did not yield a similar feature.

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