TY - JOUR
T1 - Detailed chemical compositions of planet-hosting stars a- I. Exploration of possible planet signatures
AU - Liu, F.
AU - Yong, D.
AU - Asplund, M.
AU - Wang, H. S.
AU - Spina, L.
AU - Acunã, L.
AU - Meléndez, J.
AU - Ramírez, I.
N1 - Funding Information:
The authors wish to recognize and acknowledge the very significant cultural role and reverence that the summit of Maunakea has always had within the indigenous Hawaiian community. We are most fortunate to have the opportunity to conduct observations from this mountain. Australian community access to the Keck Observatory was supported through the Australian Government’s National Collaborative Research Infrastructure Strategy, via the Department of Education and Training, and an Australian Government astronomy research infrastructure grant, via the Department of Industry and Science. This work has made use of data from the European Space Agency (ESA) mission Gaia (https://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, ht tps://www.cosmos.esa.int/web/gaia/dpac/consortium). Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement. We gratefully acknowledge support from the Australian Research Council (grants FL110100012, FT140100554, and DP120100991). FL acknowledges support from the grant ‘The New Milky Way’ from the Knut and Alice Wallenberg Foundation and the grant 184/14 from the Swedish National Space Agency. Contributions of HSW were carried out within the framework of the NCCR PlanetS (Project 4.2) supported by the Swiss National Science Foundation. LS acknowledges financial support from the Australian Research Council (Discovery Project 170100521) and from the Australian Research Council Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D) through project number CE170100013. JM thanks support from FAPESP (2018/04055-8) and CNPq (Bolsa de Produtividade). FL acknowledges suggestions from Professor Michael Murphy during manuscript writing. At last, we thank the referee for the valuable comments that helped to improve our paper.
Funding Information:
The data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation.
Funding Information:
1IRAF is distributed by the National Optical Astronomy Observatories, which are operated by the Association of Universities for Research in Astronomy, Inc., under cooperative agreement with the National Science Foundation. 2QOYLLUR-QUIPU or Q2 is a PYTHON package available online at https://gith ub.com/astroChasqui/q2.
Publisher Copyright:
© 2020 Oxford University Press. All rights reserved.
PY - 2020/7
Y1 - 2020/7
N2 - We present a line-by-line differential analysis of a sample of 16 planet-hosting stars and 68 comparison stars using high-resolution, high signal-to-noise ratio spectra gathered using Keck. We obtained accurate stellar parameters and high-precision relative chemical abundances with average uncertainties in Teff, log g, [Fe/H], and [X/H] of 15 K, 0.034 cm sa '2, 0.012 dex, and 0.025 dex, respectively. For each planet host, we identify a set of comparison stars and examine the abundance differences (corrected for Galactic chemical evolution effect) as a function of the dust condensation temperature, Tcond, of the individual elements. While we confirm that the Sun exhibits a negative trend between abundance and Tcond, we also confirm that the remaining planet hosts exhibit a variety of abundancea-Tcondtrends with no clear dependence upon age, metallicity, or Teff. The diversity in the chemical compositions of planet-hosting stars relative to their comparison stars could reflect the range of possible planet-induced effects present in these planet hosts, from the sequestration of rocky material (refractory poor) to the possible ingestion of planets (refractory rich). Other possible explanations include differences in the time-scale, efficiency and degree of planet formation, or inhomogeneous chemical evolution. Although we do not find an unambiguous chemical signature of planet formation among our sample, the high-precision chemical abundances of the host stars are essential for constraining the composition and structure of their exoplanets.
AB - We present a line-by-line differential analysis of a sample of 16 planet-hosting stars and 68 comparison stars using high-resolution, high signal-to-noise ratio spectra gathered using Keck. We obtained accurate stellar parameters and high-precision relative chemical abundances with average uncertainties in Teff, log g, [Fe/H], and [X/H] of 15 K, 0.034 cm sa '2, 0.012 dex, and 0.025 dex, respectively. For each planet host, we identify a set of comparison stars and examine the abundance differences (corrected for Galactic chemical evolution effect) as a function of the dust condensation temperature, Tcond, of the individual elements. While we confirm that the Sun exhibits a negative trend between abundance and Tcond, we also confirm that the remaining planet hosts exhibit a variety of abundancea-Tcondtrends with no clear dependence upon age, metallicity, or Teff. The diversity in the chemical compositions of planet-hosting stars relative to their comparison stars could reflect the range of possible planet-induced effects present in these planet hosts, from the sequestration of rocky material (refractory poor) to the possible ingestion of planets (refractory rich). Other possible explanations include differences in the time-scale, efficiency and degree of planet formation, or inhomogeneous chemical evolution. Although we do not find an unambiguous chemical signature of planet formation among our sample, the high-precision chemical abundances of the host stars are essential for constraining the composition and structure of their exoplanets.
KW - Planets And Satellites: Terrestrial Planets
KW - Stars: Abundances
KW - Stars: Atmospheres
UR - http://www.scopus.com/inward/record.url?scp=85094924560&partnerID=8YFLogxK
U2 - 10.1093/MNRAS/STAA1420
DO - 10.1093/MNRAS/STAA1420
M3 - Article
AN - SCOPUS:85094924560
SN - 0035-8711
VL - 495
SP - 3961
EP - 3973
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
IS - 4
ER -