Three planets around HD 27894

• Verfasst von: Trifonov, Trifon [VerfasserIn]
• Verfasst von: Reffert, Sabine [VerfasserIn]
• Verfasst von: Brems, Stefan S. [VerfasserIn]
• Titel: Three planets around HD 27894
• Titelzusatz: a close-in pair with a 2:1 period ratio and an eccentric Jovian planet at 5.4 AU
• Verf.angabe: T. Trifonov, M. Kürster, M. Zechmeister, O.V. Zakhozhay, S. Reffert, M.H. Lee, F. Rodler, S.S. Vogt, and S.S. Brems
• Fussnoten: Gesehen am 11.10.2017
• Titel Quelle: Enthalten in: De.arxiv.org
• Jahr Quelle: 2017
• Band/Heft Quelle: (2017) Artikel-Nummer 1706.00509, 5 Seiten
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1564282937

Abstract

Aims. Our new program with HARPS aims to detect mean motion resonant planetary systems around stars which were previously reported to have a single bona fide planet, often based only on sparse radial velocity data. Methods. Archival and new HARPS radial velocities for the K2V star HD 27894 were combined and fitted with a three-planet self-consistent dynamical model. The best-fit orbit was tested for long-term stability. Results. We find clear evidence that HD 27894 is hosting at least three massive planets. In addition to the already known Jovian planet with a period $P_{\rm b}$ $\approx$ 18 days we discover a Saturn-mass planet with $P_{\rm c}$ $\approx$ 36 days, likely in a 2:1 mean motion resonance with the first planet, and a cold massive planet ($\approx$ 5.3 $M_{\mathrm{Jup}}$) with a period $P_{\rm d}$ $\approx$ 5170 days on a moderately eccentric orbit (