Direct imaging search of young jovian exoplanets with JWST NIRCam

Stable and extremely sensitive in the near-infrared, JWST extends the detection parameter space to sub-Jupiter and/or temperate (down to 250 to 400 K effective temperature) exoplanets for the first time. We present a group of 3 NIRCam coronagraphic survey guest observer programs (4050, 5835, 6005) in cycles 2 and 3 that targeted 170 nearby young stars at 2.0 and 4.4µm simultaneously. In the first epochs, we have detected about two thousand sources in the 20-arcsecond field of view (long wavelength channel). The majority of those sources are background galaxies and we use the F200W-F444W colors to grossly discriminate them from potential exoplanets. As this process isn’t proof of false positives we also need to check for common proper motion by means of a second epoch. We have hence proposed follow-up observations for the most promising point sources, potential candidate companions. Around each of our stars, we reach a 0.5 MJup sensitivity and in one third of them, we could even potentially detect young Saturn-mass planets! Our survey has also yield numerous debris disk detections, including some first-ever scattered light detections around M and K host stars. To achieve these results, our teams have had to develop and adapt state of the art PSF subtraction and post-processing techniques, making use of curated reference star libraries built with the sample itself. We will briefly describe the associated challenges and how we overcame them.