2010ApJ...722.1854W -
Astrophys. J., 722, 1854-1863 (2010/October-3)
The frequency of low-mass exoplanets. II. The "Period valley".
WITTENMYER R.A., O'TOOLE S.J., JONES H.R.A., TINNEY C.G., BUTLER R.P., CARTER B.D. and BAILEY J.
Abstract (from CDS):
Radial-velocity planet search campaigns are now beginning to detect low-mass "Super-Earth" planets, with minimum masses M sin i≲ 10 M⊕. Using two independently developed methods, we have derived detection limits from nearly four years of the highest-precision data on 24 bright, stable stars from the Anglo-Australian Planet Search. Both methods are more conservative than a human analyzing an individual observed data set, as is demonstrated by the fact that both techniques would detect the radial-velocity signals announced as exoplanets for the 61 Vir system in 50% of trials. There are modest differences between the methods which can be recognized as arising from particular criteria that they adopt. What both processes deliver is a quantitative selection process such that one can use them to draw quantitative conclusions about planetary frequency and orbital parameter distribution from a given data set. Averaging over all 24 stars, in the period range P< 300 days and the eccentricity range 0.0 < e < 0.6, we could detect 99% of planets with velocity amplitudes K≳ 7.1 m/s. For the best stars in the sample, we are able to detect or exclude planets with K≳ 3 m/s, corresponding to minimum masses of 8 M⊕(P = 5 days) or 17 M⊕ (P = 50 days). Our results indicate that the observed "period valley," a lack of giant planets (M > 100 M⊕) with periods between 10 and 100 days, is indeed real. However, for planets in the mass range 10-100 M⊕, our results suggest that the deficit of such planets may be a result of selection effects.
Abstract Copyright:
∼
Journal keyword(s):
planetary systems - techniques: radial velocities
Simbad objects:
30
Full paper
View the references in ADS
To bookmark this query, right click on this link: simbad:2010ApJ...722.1854W and select 'bookmark this link' or equivalent in the popup menu