Extrasolar planets and brown dwarfs around A-F type stars. VI. High precision RV survey of early type dwarfs with HARPS

By Anne-Marie Lagrange, M. Desort, F. Galland, S. Udry, M. Mayor. 2008

284 citations recorded by the source corpus.

(Abridged) Aims: Systematic surveys to search for exoplanets have been mostly dedicated to solar-type stars sofar. We developed in 2004 a method to extend such searches to earlier A-F type dwarfs and started spectroscopic surveys to search for planets and quantify the detection limit achievable when taking into account the stars properties and their actual levels of intrinsic variations. We give here the first results of our southern survey with HARPS. Results: 1) 64% of the 170 stars with enough data points are found to be variable. 20 are found to be binaries or candidate binaries (with stars or brown dwarfs). More than 80% or the latest type stars (once binaries are removed) are intrinsically variable at a 2 m/s precision level. Stars with earlier spectral type (B-V <= 0.2) are either variable or associated to levels of uncertainties comparable to the RV rms observed on variable stars of same B-V. 2) We have detected one long-period planetary system around an F6IV-V star. 3) We have quantified the jitter due to stellar activity and we show that taking into account this jitter in addition to the stellar parameters, it is still possible to detect planets with HARPS with periods of 3 days (resp. 10 days and 100 days) on 91% (resp. 83%, 61%) of them. We show that even the earliest spectral type stars are accessible to this type of search, provided they have a low vsini and low levels of activity. 4) Taking into account the present data, we compute the actually achieved detection limits for 107 targets and discuss the limits as a function of B-V. Given the data at hand, our survey is sensitive to short-period (few days) planets and to longer ones (100 days) at a lower extent (latest type stars). We derive first constrains on the presence of planets around A-F stars for these ranges of periods.

Subfields: Astronomy and Astrophysics, Computational Mechanics, Instrumentation

View Paper: https://www.semanticscholar.org/paper/13e1b2e1f9d124e2298c58260d84292a0e401688

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Astronomy and Astrophysics

1. J. Johnson
2. G. Marcy
3. J. Southworth
4. B. Bowler
5. Debra A. Fischer
6. G. Henry
7. Timothy Morton
8. Michael C. Liu

In Computational Mechanics

1. B. Bowler
2. Debra A. Fischer
3. J. Johnson
4. G. Marcy
5. J. Southworth
6. G. Henry
7. Michael C. Liu

In Instrumentation

1. G. Marcy
2. J. Johnson
3. B. Bowler
4. J. Southworth
5. Debra A. Fischer
6. G. Henry
7. Michael C. Liu
8. K. Peek

Citations in the corpus

• RETIRED A STARS AND THEIR COMPANIONS. III. COMPARING THE MASS–PERIOD DISTRIBUTIONS OF PLANETS AROUND A-TYPE STARS AND SUN-LIKE STARS (2009, methodology): “IM main sequence stars and giants both have higher mean jitter levels than subgiants (e.g., Lagrange et al. 2009a; Setiawan et al. 2003b); transit or microlensing surveys may therefore be the only tools available to study subNeptune-mass planets in circular orbits around IM stars, although the…”
• Searching for faint companions with VLTI/PIONIER - II. 92 main sequence stars from the Exozodi survey (2014, background): “Tet Ind has also been shown to have a constant radial velocity in the survey of Lagrange et al. (2009).”
• Precise Radial Velocities of Giant Stars VII. Occurrence Rate of Giant Extrasolar Planets as a Function of Mass and Metallicity (2014, methodology): “Based on observations collected at Lick Observatory, University of California 1 http://www.exoplanets.org/ 2005a; Lagrange et al. 2009).”
• Homogeneous studies of transiting extrasolar planets - III. Additional planets and stellar models (2010, background): “24) shows a much larger scatter in the planet properties, but also that systematic er- not been neglecting ones more massive than this; see Gallandet al. (2005), Johnson et al. (2007) Lagrange et al. (2009) and Bowler et al.(2010). rors are much less important for these objects.”