AR 3905 (Archival Research)

Fri Jun 14 22:56:14 GMT 2024

Principal Investigator: Benjamin Johnson
PI Institution: Harvard University
Investigators (xml)

Title: Data-Driven Wisp Templates and Flat Fields for NIRCam
Cycle: 2

Extracting the most information from JWST NIRCam observations requires addressing several known issues in the NIRCam images such as wisps. We propose to use extensive NIRCam imaging that has been taken during Cycle 1 to construct a large dataset of pixels that have seen only astrophysical and telescope backgrounds. We will use these these pixels to extract, via matrix decomposition, a number of NIRCam background 'templates' that describe the morphology of the wisp straylight and its variation. We will also use the dataset to construct high signal-to-noise \`sky flats', both through robust stacking and from components of the matrix decomposition which naturally account for varying backgrounds. We will look for indications of any other effects that may have stable spatial distributions but vary in amplitude. These analyses will require extensive masking of flux from stars and and galaxies. We will release the wisp templates and flat fields to the community along with tools for their use.