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Arxiv: Searching for Planets Orbiting Vega with the James Webb Space Telescope Published: 10/22/2024 1:21:26 AM Updated: 10/22/2024 1:21:26 AM

Paper abstract: The most prominent of the IRAS debris disk systems, \alpha Lyrae (Vega), ata distance of 7.7 pc, has been observed by both the NIRCam and MIRI instrumentson the James Webb Space Telescope (JWST). This paper describes NIRCamcoronagraphic observations which have achieved F444W contrast levels of3\times10^{-7} at 1\arcsec\ (7.7 au), 1\times10^{-7} at 2\arcsec\ (15 au)and few \times 10^{-8} beyond 5\arcsec\ (38 au), corresponding to masses of< 3, 2 and 0.5 MJup for a system age of 700 Myr. Two F444W objects areidentified in the outer MIRI debris disk, around 48 au. One of these isdetected by MIRI, appears to be extended and has a spectral energy distributionsimilar to those of distant extragalactic sources. The second one also appearsextended in the NIRCam data suggestive of an extragalactic nature.The NIRCamlimits within the inner disk (1\arcsec\ --10\arcsec) correspond to amodel-dependent masses of 2~3 \mj. \citet{Su2024} argue that planetslarger even 0.3 MJup would disrupt the smooth disk structure seen at MIRIwavelengths. Eight additional objects are found within 60\arcsec\ of Vega, butnone has astrometric properties or colors consistent with planet candidates.These observations reach a level consistent with expected Jeans Mass limits.Deeper observations achieving contrast levels <10^{-8} outside of~4\arcsec\ and reaching masses below that of Saturn are possible, but maynot reveal a large population of new objects.