TOI-3984 A b and TOI-5293 A b: two temperate gas giants transiting mid-M dwarfs in wide binary systems

• Published in: arXiv.org
• Main Authors: Cañas, Caleb I, Kanodia, Shubham, Libby-Roberts, Jessica, Lin, Andrea S J, Schutte, Maria, Powers, Luke, Jones, Sinclaire, Monson, Andrew, Wang, Songhu, Stefánsson, Guðmundur, Cochran, William D, Robertson, Paul, Mahadevan, Suvrath, Kowalski, Adam F, Wisniewski, John, Parker, Brock A, Larsen, Alexander, Chapman, Franklin A L, Kobulnicky, Henry A, Gupta, Arvind F, Everett, Mark E, Penprase, Bryan Edward, Zeimann, Gregory, Beard, Corey, Bender, Chad F, Colón, Knicole D, Diddams, Scott A, Connor, Fredrick, Halverson, Samuel, Ninan, Joe P, Ramsey, Lawrence W, Roy, Arpita, Schwab, Christian
• Format: Paper Journal Article
• Language: English
• Published: Ithaca Cornell University Library, arXiv.org 27.06.2023
• Subjects: Binary stars; Circumstellar habitable zone; Computer architecture; Extrasolar planets; Gas giant planets; Jupiter; Physics - Earth and Planetary Astrophysics; Physics - Solar and Stellar Astrophysics; Red dwarf stars; Separation; Spectrographs; White dwarf stars
• ISSN: 2331-8422
• DOI: 10.48550/arxiv.2302.07714

We confirm the planetary nature of two gas giants discovered by TESS to transit M dwarfs with stellar companions at wide separations. TOI-3984 A (\(J=11.93\)) is an M4 dwarf hosting a short-period (\(4.353326 \pm 0.000005\) days) gas giant (\(M_p=0.14\pm0.03~\mathrm{M_{J}}\) and \(R_p=0.71\pm0.02~\mathrm{R_{J}}\)) with a wide separation white dwarf companion. TOI-5293 A (\(J=12.47\)) is an M3 dwarf hosting a short-period (\(2.930289 \pm 0.000004\) days) gas giant (\(M_p=0.54\pm0.07~\mathrm{M_{J}}\) and \(R_p=1.06\pm0.04~\mathrm{R_{J}}\)) with a wide separation M dwarf companion. We characterize both systems using a combination of ground-based and space-based photometry, speckle imaging, and high-precision radial velocities from the Habitable-zone Planet Finder and NEID spectrographs. TOI-3984 A b (\(T_{eq}=563\pm15\) K and \(\mathrm{TSM}=138_{-27}^{+29}\)) and TOI-5293 A b (\(T_{eq}=675_{-30}^{+42}\) K and \(\mathrm{TSM}=92\pm14\)) are two of the coolest gas giants among the population of hot Jupiter-sized gas planets orbiting M dwarfs and are favorable targets for atmospheric characterization of temperate gas giants and three-dimensional obliquity measurements to probe system architecture and migration scenarios.