J/A+A/593/A38 SPOTS II. Planets Orbiting Two Stars (Bonavita+, 2016)
SPOTS: The Search for Planets Orbiting Two Stars.
II. First constraints on the frequency of sub-stellar companions on wide
circumbinary orbits.
Bonavita M., Desidera S., Thalmann C., Janson M., Vigan A., Chauvin G.,
Lannier J.
<Astron. Astrophys., 593, A38 (2016)>
=2016A&A...593A..38B 2016A&A...593A..38B (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Binaries, spectroscopic ; Planets
Keywords: binaries: visual - binaries: spectroscopic
Abstract:
A large number of direct imaging surveys for exoplanets have been
performed in recent years, yielding the first directly imaged planets
and providing constraints on the prevalence and distribution of wide
planetary systems. However, like most of the radial velocity ones,
these generally focus on single stars, hence binaries and higher-order
multiples have not been studied to the same level of scrutiny. This
motivated the Search for Planets Orbiting Two Stars (SPOTS) survey,
which is an ongoing direct imaging study of a large sample of close
binaries, started with VLT/NACO and now continuing with VLT/SPHERE. To
complement this survey, we have identified the close binary targets in
24 published direct imaging surveys. Here we present our statistical
analysis of this combined body of data. We analysed a sample of 117
tight binary systems, using a combined Monte Carlo and Bayesian
approach to derive the expected values of the frequency of companions,
for different values of the companion's semi-major axis. Our analysis
suggest that the frequency of sub-stellar companions in wide orbit is
moderately low (=>13% with a best value of 6% at 95% confidence level)
and not significantly different between single stars and tight
binaries. One implication of this result is that the very high
frequency of circumbinary planets in wide orbits around post-common
envelope binaries, implied by eclipse timing, cannot be uniquely due
to planets formed before the common-envelope phase (first generation
planets), supporting instead the second generation planet formation or
a non-Keplerian origin of the timing variations.
Description:
We present a statistical analysis of the combined body of existing
high-contrast imaging constraints on circumbinary planets, to
complement our ongoing SPOTS direct imaging survey dedicated to
such planets. The sample of stars considered includes 117 objects and
comes from a search for tight binaries within the target lists of 23
published direct imaging surveys, including some of the deepest ones
performed to data.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tableb1.dat 160 117 CBIN sample
refs.dat 64 26 References
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Byte-by-byte Description of file: tableb1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- Seq Sequentail number
5- 29 A25 --- Star Star name
31- 32 I2 h RAh Right ascension (J2000)
34- 35 I2 min RAm Right ascension (J2000)
37- 42 F6.3 s RAs Right ascension (J2000)
44 A1 --- DE- Declination sign (J2000)
45- 46 I2 deg DEd Declination (J2000)
48- 49 I2 arcmin DEm Declination (J2000)
51- 55 F5.2 arcsec DEs Declination (J2000)
57- 62 F6.2 pc Dist Distance
63 A1 --- n_Dist [n] Note on Dist not explained in the paper
65- 68 I4 Myr Age Age
70- 75 F6.3 mag Hmag ?=- H magnitude
77- 86 A10 --- SpType MK spectral type
87- 92 F6.3 Msun MA Mass of component A
94 A1 -- l_MB [∼ <>] Limit flag on MB
95- 99 F5.3 Msun MB ?=- Mass of component B
101-102 A2 --- l_rho [≤ ~] Limit flag on rho
103-109 F7.5 arcsec rho ?=- Angular separation
110 A1 --- l_Per [~] Limit flag on Per
111-119 F9.3 --- Per ? Period
120-121 A2 --- x_Per [yr d] Period unit
122 A1 --- l_Ecc [~] Limit flag on Ecc
123-127 F5.3 --- Ecc ?=- Eccentricity
129-130 A2 --- l_acrit [≤ ~] Limit flag on acrit
131-136 F6.3 AU acrit Limit for the presence of circumbinary planet
138-160 A23 --- Ref References, in refs.dat file
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Byte-by-byte Description of file: refs.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- Ref Reference code
6- 24 A19 --- BibCode BibCode
26- 42 A17 -- Aut Author's name
46- 64 A19 --- Com Comments
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History:
From electronic version of the journal
References:
Thalmann et al., Paper I 2014A&A...572A..91T 2014A&A...572A..91T
(End) Patricia Vannier [CDS] 10-Nov-2016