Deconvolution of JWST/MIRI Images: Applications to an Active Galactic Nucleus Model and GATOS Observations of NGC 5728

Leist, M. T.; Packham, C.; Rosario, D. J. V.; Hope, D. A.; Alonso-Herrero, A.; Hicks, E. K. S.; Hönig, S.; Zhang, L.; Davies, R.; Díaz-Santos, T.; González-Martín, O.; Bellocchi, E.; Boorman, P. G.; Combes, F.; García-Bernete, I.; García-Burillo, S.; García-Lorenzo, B.; Haidar, H.; Ichikawa, K.; Imanishi, M.; Jefferies, S. M.; Labiano, Á.; Levenson, N. A.; Nikutta, R.; Pereira-Santaella, M.; Ramos Almeida, C.; Ricci, C.; Rigopoulou, D.; Schaefer, W.; Stalevski, M.; Ward, M. J.; Fuller, L.; Izumi, T.; Rouan, D.; Shimizu, T.

Abstract

The superb image quality, stability, and sensitivity of JWST permit deconvolution techniques to be pursued with a fidelity unavailable to ground-based observations. We present an assessment of several deconvolution approaches to improve image quality and mitigate the effects of the complex JWST point-spread function (PSF). The optimal deconvolution method is determined by using WebbPSF to simulate JWST’s complex PSF and MIRISim to simulate multiband JWST/Mid-Infrared Imager Module (MIRIM) observations of a toy model of an active galactic nucleus (AGN). Five different deconvolution algorithms are tested: (1) Kraken deconvolution, (2) Richardson–Lucy, (3) the adaptive imaging deconvolution algorithm, (4) sparse regularization with the Condat–Vũ algorithm, and (5) iterative Wiener filtering and thresholding. We find that Kraken affords the greatest FWHM reduction of the nuclear source of our MIRISim observations for the toy AGN model while retaining good photometric integrity across all simulated wave bands. Applying Kraken to Galactic Activity, Torus, and Outflow Survey (GATOS) multiband JWST/MIRIM observations of the Seyfert 2 galaxy NGC 5728, we find that the algorithm reduces the FWHM of the nuclear source by a factor of 1.6–2.2 across all five filters. Kraken images facilitate detection of extended nuclear emission ∼2.″5 (∼470 pc, position angle ≃ 115°) in the SE–NW direction, especially at the longest wavelengths. We demonstrate that Kraken is a powerful tool to enhance faint features otherwise hidden in the complex JWST PSF.

Citation

Leist, M. T., Packham, C., Rosario, D. J. V., Hope, D. A., Alonso-Herrero, A., Hicks, E. K. S., …Shimizu, T. (2024). Deconvolution of JWST/MIRI Images: Applications to an Active Galactic Nucleus Model and GATOS Observations of NGC 5728. Astronomical Journal, 167(3), Article 96. https://doi.org/10.3847/1538-3881/ad1886

• Journal Article Type: Article
• Acceptance Date: Dec 21, 2023
• Online Publication Date: Feb 7, 2024
• Publication Date: Mar 1, 2024
• Deposit Date: Mar 13, 2024
• Publicly Available Date: Mar 13, 2024
• Journal: The Astronomical Journal
• Print ISSN: 0004-6256
• Publisher: IOP Publishing
• Peer Reviewed: Peer Reviewed
• Volume: 167
• Issue: 3
• Article Number: 96
• DOI: https://doi.org/10.3847/1538-3881/ad1886
• Keywords: Active galactic nuclei, James Webb Space Telescope, Deconvolution
• Public URL: https://durham-repository.worktribe.com/output/2234552