Reliable determination of the mid-infrared thermal continuum in JWST/MIRI spectra of NGC 1514

Develop a robust approach or obtain suitable observations to reliably fit and determine the mid-infrared thermal dust continuum in the JWST MIRI Medium Resolution Spectrometer spectra of NGC 1514’s rings and inner shell, overcoming baseline inflections introduced by cosmic ray events in both source and background exposures.

Background

The MIRI spectra of NGC 1514 are dominated by bright lines ([S IV] 10.511 μm, [Ne III] 15.555 μm, [O IV] 25.890 μm). The authors attempted to fit thermal continua but encountered baseline inflections due to the cosmic ray history of both source and background observations, preventing reliable continuum determination.

Because the continuum could not be fitted, quantitative dust SED modeling based directly on the spectra was not possible; instead, the authors relied on imaging color-color ratios to infer approximate dust color temperatures (~200 K from F770W/F1280W and ~110 K from F1280W/F2550W).