The peculiar chemical pattern of the WASP-160 binary system: signatures of planetary formation and evolution?

EMILIANO JOFRÉ; ROMINA PETRUCCI; YILEN GÓMEZ MAQUEO CHEW; IVÁN RAMÍREZ; CARLOS SAFFE; EDER MARTIOLI; ANDREA BUCCINO; MARTIN MASEK; LUCIANO GARCÍA; ELIAB CANUL CANCHÉ; MERCEDES GÓMEZ

ASTRONOMICAL JOURNAL

IOP PUBLISHING LTD

Lugar: Londres; Año: 2021

0004-6256

Wide binary stars with similar components hosting planets provide a favorable opportunity forexploring the star-planet chemical connection. We perform a detailed characterization of the solar type stars in the WASP-160 binary system. No planet has been reported yet around WASP-160Awhile WASP-160B is known to host a transiting Saturn-mass planet, WASP-160B b. For this planet,we also derive updated properties from both literature and new observations. Furthermore, usingTESS photometry, we constrain the presence of transiting planets around WASP-160A and additionalones around WASP-160B. The stellar characterization includes, for the first time, the computation ofhigh-precision differential atmospheric and chemical abundances of 25 elements based on high-quality Gemini-GRACES spectra. Our analysis reveals evidence of a correlation between the differentialabundances and the condensation temperatures of the elements. In particular, we find both a smallbut significant deficit of volatiles and an enhancement of refractory elements in WASP-160B relativeto WASP-160A. After WASP-94, this is the second stellar pair among the shortlist of planet-hostingbinaries showing this kind of peculiar chemical pattern. Although we discuss several plausible planetformation and evolution scenarios for WASP-160A and B that could explain the observed chemicalpattern, none of them can be conclusively accepted or rejected. Future high-precision photometric andspectroscopic follow-up, as well as high-contrast imaging observations, of WASP-160A and B, mightprovide further constraints on the real origin of the detected chemical differences.