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Title: Mid-to-late M Dwarfs Lack Jupiter Analogs
Abstract Cold Jovian planets play an important role in sculpting the dynamical environment in which inner terrestrial planets form. The core accretion model predicts that giant planets cannot form around low-mass M dwarfs, although this idea has been challenged by recent planet discoveries. Here, we investigate the occurrence rate of giant planets around low-mass (0.1–0.3M⊙) M dwarfs. We monitor a volume-complete, inactive sample of 200 such stars located within 15 pc, collecting four high-resolution spectra of each M dwarf over six years and performing intensive follow-up monitoring of two candidate radial velocity variables. We use TRES on the 1.5 m telescope at the Fred Lawrence Whipple Observatory and CHIRON on the Cerro Tololo Inter-American Observatory 1.5 m telescope for our primary campaign, and MAROON-X on Gemini-North for high-precision follow up. We place a 95% confidence upper limit of 1.5% (68% confidence limit of 0.57%) on the occurrence ofMPsini> 1MJgiant planets out to the water snow line and provide additional constraints on the giant planet population as a function ofMPsiniand period. Beyond the snow line (100 K <Teq< 150 K), we place 95% confidence upper limits of 1.5%, 1.7%, and 4.4% (68% confidence limits of 0.58%, 0.66%, and 1.7%) for 3MJ<MPsini< 10MJ, 0.8MJ<MPsini< 3MJ, and 0.3MJ<MPsini< 0.8MJgiant planets, respectively; i.e., Jupiter analogs are rare around low-mass M dwarfs. In contrast, surveys of Sun-like stars have found that their giant planets are most common at these Jupiter-like instellations.  more » « less
Award ID(s):
2108465
PAR ID:
10514022
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Publisher / Repository:
AAS
Date Published:
Journal Name:
The Astronomical Journal
Volume:
166
Issue:
1
ISSN:
0004-6256
Page Range / eLocation ID:
11
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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