Beta Pictoris

JWST-TST High Contrast: JWST/NIRCam Observations Of The Young Giant Planet β Pic b

By Keith Cowing
Press Release
May 30, 2024
Filed under , , , , , , , , , ,
JWST-TST High Contrast: JWST/NIRCam Observations Of The Young Giant Planet β Pic b
PSF-subtracted JWST/NIRCam (left) and MIRI (right) images of the β Pic system (arbitrary color stretch). Five background sources were identified based on their NIRCam colors or morphology whose positions are highlighted in both images with red circles. The orange circles in the NIRCam image show the source positions rotated by the telescope roll angle, where negative ADI residuals are visible. BG4 appears to be the only source which is also visible in the MIRI image. The MIRI image was adapted from Rebollido et al. (2024). — astro-ph.EP

We present the first JWST/NIRCam observations of the directly-imaged gas giant exoplanet β Pic b. Observations in six filters using NIRCam’s round coronagraphic masks provide a high signal-to-noise detection of β Pic b and the archetypal debris disk around β Pic over a wavelength range of ∼1.7-5 μm.

This paper focuses on the detection of β Pic b and other potential point sources in the NIRCam data, following a paper by Rebollido et al. which presented the NIRCam and MIRI view of the debris disk around β Pic. We develop and validate approaches for obtaining accurate photometry of planets in the presence of bright, complex circumstellar backgrounds. By simultaneously fitting the planet’s PSF and a geometric model for the disk, we obtain planet photometry that is in good agreement with previous measurements from the ground.

The NIRCam data supports the cloudy nature of β Pic b’s atmosphere and the discrepancy between its mass as inferred from evolutionary models and the dynamical mass reported in the literature. We further identify five additional localized sources in the data, but all of them are found to be background stars or galaxies based on their color or spatial extent.

We can rule out additional planets in the disk midplane above 1 Jupiter mass outward of 2 arcsec (∼40 au) and away from the disk midplane above 0.05 Jupiter masses outward of 4 arcsec (∼80 au). The inner giant planet β Pic c remains undetected behind the coronagraphic masks of NIRCam in our observations.

MCRDI-modeling of β Pic b. The six rows show the six observed filters and the three columns show the host star PSF- and disk model-subtracted images (left), the best fit planet PSF models (middle), and the residuals between the two (right). The position of the host star β Pic is indicated with a black star. F250M and F300M are particularly affected by spatial undersampling and the PSF subtraction has higher residuals for these filters. — astro-ph.EP

Jens Kammerer, Kellen Lawson, Marshall D. Perrin, Isabel Rebollido, Christopher C. Stark, Tomas Stolker, Julien H. Girard, Laurent Pueyo, William O. Balmer, Kadin Worthen, Christine Chen, Roeland P. van der Marel, Nikole K. Lewis, Kimberly Ward-Duong, Jeff A. Valenti, Mark Clampin, C. Matt Mountain

Comments: 30 pages, 14 figures, accepted for publication in AJ
Subjects: Earth and Planetary Astrophysics (astro-ph.EP); Instrumentation and Methods for Astrophysics (astro-ph.IM)
Cite as: arXiv:2405.18422 [astro-ph.EP] (or arXiv:2405.18422v1 [astro-ph.EP] for this version)
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Submission history
From: Jens Kammerer
[v1] Tue, 28 May 2024 17:58:52 UTC (6,784 KB)


Explorers Club Fellow, ex-NASA Space Station Payload manager/space biologist, Away Teams, Journalist, Lapsed climber, Synaesthete, Na’Vi-Jedi-Freman-Buddhist-mix, ASL, Devon Island and Everest Base Camp veteran, (he/him) 🖖🏻