No evidence of the planet orbiting the extremely metal-poor extragalactic star HIP13044

Abstract

CONTEXT: The recent discovery of three giant planets orbiting the extremely metal-poor stars HIP11952 and HIP13044 have challenged theoretical predictions of the core-accretion model. According to this, the metal content of the protoplanetary disk from which giant planets are formed is a key ingredient for the early formation of planetesimals prior to the runaway accretion of the surrounding gas. AIMS: We reanalyzed the original FEROS data that were used to detect the planets to prove or refute their existence, employing our new reduction and analysis methods. METHOD: We applied the cross-correlation technique to FEROS spectra to measure the radial velocity variation of HIP13044 and HIP11952. We reached a typical precision of $\sim$ 35 $m{s}^{-1}$ for HIP13044 and $\sim$ 25 $m{s}^{-1}$ for HIP11952, which is significantly superior to the uncertainties presented previously. RESULTS: We found no evidence of the planet orbiting the metal-poor extragalactic star HIP13044. We show that given our radial velocity precision, and considering the large number of radial velocity epochs, the probability for a non-detection of the radial velocity signal recently claimed is lower than 10${}^{-4}$. Finally, we also confirm findings that the extremely metal-poor star HIP11952 does not contain a system of two gas giant planets. These results reaffirm the expectations from the core-accretion model of planet formation.

Accepted in A&A

References in corpus (4)

• The HARPS search for southern extra-solar planets. XIII. A planetary system with 3 Super-Earths (4.2, 6.9, & 9.2 Earth masses)
• Precise radial velocities of giant stars: I. Stable stars
• A Giant Planet Around a Metal-poor Star of Extragalactic Origin
• Planetary companions around the metal-poor star HIP 11952

Cited by in corpus (19)

• An ancient extrasolar system with five sub-Earth-size planets
• A Kepler Study of Starspot Lifetimes with Respect to Light Curve Amplitude and Spectral Type
• Two planets around Kapteyn's star : a cold and a temperate super-Earth orbiting the nearest halo red-dwarf
• The properties of planets around giant stars
• Giant planets around two intermediate-mass evolved stars and confirmation of the planetary nature of HIP67851 c
• A planetary system and a highly eccentric brown dwarf around the giant stars HIP67851 and HIP97233
• The Pan-Pacific Planet Search. IV. Two super-Jupiters in a 3:5 resonance orbiting the giant star HD33844
• Planet Traps and First Planets: the Critical Metallicity for Gas Giant Formation
• An eccentric companion at the edge of the brown dwarf desert orbiting the 2.4 Msun giant star HIP67537
• Giant planet engulfment by evolved giant stars: light curves, asteroseismology, and survivability
• The test case of HD26965: difficulties disentangling weak Doppler signals from stellar activity
• A red giant branch common envelope evolution scenario for the exoplanet WD 1856 b
• Age Aspects of Habitability
• The GAPS Programme with HARPS-N at TNG XVIII. Two new giant planets around the metal-poor stars HD 220197 and HD 233832
• A search for transiting planets around hot subdwarfs II. Supplementary methods and results from TESS Cycle 1
• The quest for planets around subdwarfs and white dwarfs from Kepler space telescope fields: Part I. Techniques and tests of the methods
• Constraining the Planet Occurrence Rate around Halo Stars of Potentially Extragalactic Origin
• Rapid expansion of red giant stars during core helium flash by waves propagation to the envelope and implications to exoplanets
• Destruction of "Peas in a Pod?" A Candidate Multi-planet System Around the Nearby, Bright Star, HD208487