Stellar noise and planet detection. I. Oscillations, granulation and sun-like spots

• Tipo: Artigo em Livro de Atas de Conferência Internacional
• Data: 2011

Autores

Dumusque, X (Autor) Outra; N.C. Santos (Autor) FCUP; Udry, S (Autor) Outra; Lovis, C (Autor) Outra; Bonfils, X (Autor) Outra

Ata de Conferência Internacional

Título: ASTROPHYSICS OF PLANETARY SYSTEMS: FORMATION, STRUCTURE, AND DYNAMICAL EVOLUTION

Páginas: 527-529

276th Symposium of the International-Astronomical-Union on Astrophysics of Planetary Systems: Formation, Structure, and Dynamical Evolution

Torino, ITALY, OCT 10-15, 2010

Indexação

ISI Web of Knowledge - 2 Citações

Scopus - 1 Citação

Outras Informações

ID Authenticus: P-005-70P

DOI: 10.1017/s1743921311021089

Abstract (EN): Spectrographs like HARPS can now reach a sub-ms(-1) precision in radial-velocity (RV) (Pepe & Lovis 2008). At this level of accuracy, we start to be confronted with stellar noise produced by 3 different physical phenomena: oscillations, granulation phenomena (granulation, meso- and super-granulation) and activity. On solar type stars, these 3 types of perturbation can induce ms(-1) RV variation, but on different time scales: 3 to 15 minutes for oscillations, 15 minutes to 1.5 days for granulation phenomena and 10 to 50 clays for activity. The high precision observational strategy used on HARPS, 1 measure per night of 15 minutes, on 10 consecutive clays each month, is optimized, due to a long exposure time, to average out the noise coming from oscillations (Dumusque et al. 2011a) but not to reduce the noise coining from granulation and activity (Dumusque et al. 2011a and Dumusque et al. 2011b). The smallest planets found with this strategy (Mayor et, al. 2009) seems to be at the limit of the actual observational strategy and not at the limit of the instrumental precision. To be able to find Earth mass planets in the habitable zone of solar-type stars (200 days for a K0 dwarf), new observational strategies, averaging out simultaneously all type of stellar noise, are required.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 3