Abstract The integral-field unit spectrometers on board the James Webb Space Telescope (JWST) undersample the nearly diffraction-limited point-spread function provided by the telescope optics. This undersampling produces large oscillating spectral artifacts when the data are resampled into regularly gridded data cubes, which poses a significant challenge for many scientific analyses. We describe here a generalized technique to use cubic basis spline models to interpolate the observed spectral traces onto a higher-resolution grid prior to data cube rectification, which largely eliminates these artifacts in addition to helping reduce biases in point-source spectra from clusters of bad pixels. We demonstrate the utility of this adaptive resampling technique for a variety of JWST/NIRSpec and MIRI/Medium Resolution Spectrometer observations ranging from isolated point sources to embedded active galactic nuclei, crowded stellar fields with diffuse emission, and protostars with rich molecular bands.
Law et al. (Mon,) studied this question.