CHEMICAL CLUES ON THE FORMATION OF PLANETARY SYSTEMS: C/O VERSUS Mg/Si FOR HARPS GTO SAMPLE

• Type: Article in International Scientific Journal
• Date: 2010

Authors

Delgado Mena, ED (Author) Other; Israelian, G (Author) Other; Gonzalez Hernandez, JIG (Author) Other; Bond, JC (Author) Other; N.C. Santos (Author) FCUP; Udry, S (Author) Other; Mayor, M (Author) Other

Journal

Title: Astrophysical Journal

Vol. 725 No. 2

Pages: 2349-2358

ISSN: 0004-637X

Publisher: American Astronomical Society

Indexing

ISI Web of Knowledge - 114 Citations

Scopus - 134 Citations

Other information

Authenticus ID: P-003-0BB

DOI: 10.1088/0004-637x/725/2/2349

Abstract (EN): Theoretical studies suggest that C/O and Mg/Si are the most important elemental ratios in determining the mineralogy of terrestrial planets. The C/O ratio controls the distribution of Si among carbide and oxide species, while Mg/Si gives information about the silicate mineralogy. We present a detailed and uniform study of C, O, Mg, and Si abundances for 61 stars with detected planets and 270 stars without detected planets from the homogeneous high-quality unbiased HARPS GTO sample, together with 39 more planet-host stars from other surveys. We determine these important mineralogical ratios and investigate the nature of the possible terrestrial planets that could have formed in those planetary systems. We find mineralogical ratios quite different from those of the Sun, showing that there is a wide variety of planetary systems which are not similar to our solar system. Many planetary host stars present an Mg/Si value lower than 1, so their planets will have a high Si content to form species such as MgSiO3. This type of composition can have important implications for planetary processes such as plate tectonics, atmospheric composition, or volcanism.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10