Spectroscopic parameters for 451 stars in the HARPS GTO planet search program - Stellar [Fe/H] and the frequency of exo-Neptunes

• Type: Article in International Scientific Journal
• Date: 2008

Authors

Sousa, SG (Author) FCUP; Santos, NC (Author) Other; Mayor, M (Author) Other; Udry, S (Author) Other; Casagrande, L (Author) Other; Israelian, G (Author) Other; Pepe, F (Author) Other; Queloz, D (Author) Other; Monteiro, MJPFG (Author) FCUP

Journal

Title: Astronomy and Astrophysics

Vol. 487

Pages: 373-381

ISSN: 0004-6361

Publisher: EDP Sciences

Indexing

ISI Web of Knowledge - 447 Citations

Scopus - 455 Citations

Scientific classification

FOS: Natural sciences > Physical sciences

CORDIS: Physical sciences > Astronomy ; Physical sciences ; Physical sciences > Astronomy > Astrophysics

Other information

Authenticus ID: P-003-X4S

DOI: 10.1051/0004-6361:200809698

Resumo (PT): To understand the formation and evolution of solar-type stars in the solar neighborhood, we need to measure their stellar parameters to high accuracy. We present a catalogue of accurate stellar parameters for 451 stars that represent the HARPS Guaranteed Time Observations (GTO) “high precision” sample. Spectroscopic stellar parameters were measured using high signal-to-noise (S/N) spectra acquired with the HARPS spectrograph. The spectroscopic analysis was completed assuming LTE with a grid of Kurucz atmosphere models and the recent ARES code for measuring line equivalent widths. We show that our results agree well with those ones presented in the literature (for stars in common). We present a useful calibration for the effective temperature as a function of the index color B-V and [Fe/H]. We use our results to study the metallicity-planet correlation, namely for very low mass planets. The results presented here suggest that in contrast to their jovian couterparts, neptune-like planets do not form preferentially around metal-rich stars. The ratio of jupiter-to-neptunes is also an increasing function of stellar metallicity. These results are discussed in the context of the core-accretion model for planet formation. Based on observations collected at La Silla Observatory, ESO, Chile, with the HARPS spectrograph at the 3.6-m telescope (072.C-0488(E)). Full Tables 1 and 3 are only available in electronic form at the CDS via nonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/487/373

Abstract (EN): To understand the formation and evolution of solar-type stars in the solar neighborhood, we need to measure their stellar parameters to high accuracy. We present a catalogue of accurate stellar parameters for 451 stars that represent the HARPS Guaranteed Time Observations (GTO) "high precision" sample. Spectroscopic stellar parameters were measured using high signal-to-noise (S/N) spectra acquired with the HARPS spectrograph. The spectroscopic analysis was completed assuming LTE with a grid of Kurucz atmosphere models and the recent ARES code for measuring line equivalent widths. We show that our results agree well with those ones presented in the literature (for stars in common). We present a useful calibration for the effective temperature as a function of the index color B-V and [Fe/H]. We use our results to study the metallicity-planet correlation, namely for very low mass planets. The results presented here suggest that in contrast to their jovian couterparts, neptune-like planets do not form preferentially around metal-rich stars. The ratio of jupiter-to-neptunes is also an increasing function of stellar metallicity. These results are discussed in the context of the core-accretion model for planet formation.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 9