Wolf 359 (CN Leo, GJ 406, Gaia DR3 3864972938605115520) is a low-mass star in the fifth-closest neighboring system (2.41 pc). Because of its relative youth and proximity, Wolf 359 offers a unique opportunity to study substellar companions around M stars using infrared high-contrast imaging and radial velocity monitoring. We present the results of
We present 3D hydrodynamic models of the interaction between the outflows of evolved, pulsating, Asymptotic Giant Branch (AGB) stars and nearby (<3 stellar radii) substellar companions (Mcomp ≲ 40 MJ). Our models show that due to resonances between the orbital period of the companion and the pulsation period of the AGB star, multiple spiral structures can form; the shocks driven by the pulsations are enhanced periodically in different regions as they encounter the denser material created by the substellar companion’s wake. We discuss the properties of these spiral structures and the effect of the companion parameters on them. We also demonstrate that the gravitational potential of the nearby companion enhances the mass-loss from the AGB star. For more massive (Mcomp > 40 MJ) and more distant companions (>4 stellar radii), a single spiral arm forms. We discuss the possibility of observing these structures with the new generations of high-resolution, high-sensitivity instruments, and using them to ‘find’ substellar companions around bright, evolved stars. Our results also highlight possible structures that could form in our Solar system when the Sun turns into an AGB star.
more » « less- Award ID(s):
- 1751874
- NSF-PAR ID:
- 10367256
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Monthly Notices of the Royal Astronomical Society
- Volume:
- 513
- Issue:
- 3
- ISSN:
- 0035-8711
- Format(s):
- Medium: X Size: p. 4405-4430
- Size(s):
- ["p. 4405-4430"]
- Sponsoring Org:
- National Science Foundation
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Abstract Ms -band (4.67μ m) vector vortex coronagraphic imaging using Keck-NIRC2 and add 12 Keck-HIRES and 68 MAROON-X velocities to the radial velocity baseline. Our analysis incorporates these data alongside literature radial velocities from CARMENES, the High Accuracy Radial velocity Planet Searcher, and Keck-HIRES to rule out the existence of a close (a < 10 au) stellar or brown dwarf companion and the majority of large gas giant companions. Our survey does not refute or confirm the long-period radial velocity candidate, Wolf 359 b (P ∼ 2900 days), but rules out the candidate's existence as a large gas giant (>4M Jup) assuming an age of younger than 1 Gyr. We discuss the performance of our high-contrast imaging survey to aid future observers using Keck-NIRC2 in conjunction with the vortex coronagraph in theMs band and conclude by exploring the direct imaging capabilities with JWST to observe Jupiter- and Neptune-mass planets around Wolf 359. -
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