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Arxiv: MINDS: JWST/NIRCam imaging of the protoplanetary disk PDS 70 Published: 3/7/2024 9:09:42 PM Updated: 3/7/2024 9:09:42 PM

Paper abstract: Context. Two protoplanets have recently been discovered within the PDS 70protoplanetary disk. JWST/NIRCam offers a unique opportunity to characterizethem and their birth environment at wavelengths difficult to access from theground. Aims. We aim to image the circumstellar environment of PDS 70 at 1.87\mum and 4.83 \mum, assess the presence of Pa-\alpha emission due toaccretion onto the protoplanets, and probe any IR excess indicative of heatedcircumplanetary material. Methods. We obtain non-coronagraphic JWST/NIRCamimages of PDS 70 within the MINDS (MIRI mid-INfrared Disk Survey) program. Weleverage the Vortex Image Processing (VIP) package for data reduction, anddevelop dedicated routines for optimal stellar PSF subtraction, unbiasedimaging of the disk, and protoplanet flux measurement in this type of dataset.A radiative transfer model of the disk is used to disentangle the contributionsfrom the disk and the protoplanets. Results. We re-detect both protoplanets andidentify extended emission after subtracting a disk model, including alarge-scale spiral-like feature. We interpret its signal in the direct vicinityof planet c as tracing the accretion stream feeding its circumplanetary disk,while the outer part of the feature may rather reflect asymmetric illuminationof the outer disk. We also report a bright signal consistent with a previouslyproposed protoplanet candidate enshrouded in dust, near the 1:2:4 mean-motionresonance with planets b and c. The 1.87 \mum flux of planet b is consistentwith atmospheric model predictions, but not that of planet c. We discusspotential origins for this discrepancy, including significant Pa-\alpha lineemission. The 4.83 \mum fluxes of planets b and c suggest enshrouding dust orheated CO emission from their circumplanetary environment.