Searching for Planets Orbiting ϵ Eridani with JWST/NIRCam

We present observations of ϵ Eridani with the JWST/NIRCam coronagraph aimed at imaging planets orbiting within this system. In particular, these observations targeted (1) the Jupiter-like planet, first detected orbiting at 3.5 au with radial velocity observations, and (2) the planet postulated to be responsible for carving the edges of ϵ Eridani’s outer ring, expected to orbit at 40-50 au. However, no point sources were detected at a statistically significant level. We report new, improved upper limits at 4 μm: ∼1 × 10⁻⁶ contrast at 1″, and ∼2 × 10⁻⁸ beyond 5″. The latter contrast limit precludes Saturn-mass planets at separations >16 au given current models. We also report upper limits for ϵ Eridani’s disk emission at 4 μm. While the radial surface brightness profile shows no evidence of emission, we detect a 1σ surface brightness signal on the east side of the system, consistent with forward scattering emission expected for ϵ Eridani’s disk inclination. Finally, we evaluate the performance of the 3-roll observation strategy, which was first employed in these observations: the gains in contrast are modest, with 20%-30% improvements with respect to the conventional two-roll strategy.