J/ApJ/745/19 Binary systems in Taurus-Auriga (Kraus+, 2012)
The role of multiplicity in disk evolution and planet formation.
Kraus A.L., Ireland M.J., Hillenbrand L.A., Martinache F.
<Astrophys. J., 745, 19 (2012)>
=2012ApJ...745...19K 2012ApJ...745...19K
ADC_Keywords: Stars, double and multiple ; YSOs ; Planets
Keywords: binaries: close - binaries: visual - stars: formation -
stars: pre-main sequence - planets and satellites: formation -
protoplanetary disks
Abstract:
The past decade has seen a revolution in our understanding of
protoplanetary disk evolution and planet formation in single-star
systems. However, the majority of solar-type stars form in binary
systems, so the impact of binary companions on protoplanetary disks is
an important element in our understanding of planet formation. We have
compiled a combined multiplicity/disk census of Taurus-Auriga, plus a
restricted sample of close binaries in other regions, in order to
explore the role of multiplicity in disk evolution. Our results imply
that the tidal influence of a close (≤40AU) binary companion
significantly hastens the process of protoplanetary disk dispersal, as
∼2/3 of all close binaries promptly disperse their disks within ≲1Myr
after formation. However, prompt disk dispersal only occurs for a
small fraction of wide binaries and single stars, with ∼80%-90%
retaining their disks for at least ∼2-3Myr (but rarely for more than
∼5Myr). Our new constraints on the disk clearing timescale have
significant implications for giant planet formation; most single stars
have 3-5Myr within which to form giant planets, whereas most close
binary systems would have to form giant planets within ≲1Myr. If core
accretion is the primary mode for giant planet formation, then gas
giants in close binaries should be rare. Conversely, since almost all
single stars have a similar period of time within which to form gas
giants, their relative rarity in radial velocity (RV) surveys
indicates either that the giant planet formation timescale is very
well matched to the disk dispersal timescale or that features beyond
the disk lifetime set the likelihood of giant planet formation.
Description:
The sample we consider in this study is identical to the full sample
from Kraus et al. (2011, Cat. J/ApJ/731/8); 156 stars with spectral
types of G0-M4, of which 133 are known to be binary systems with
separations of ≲500 AU or have been surveyed for multiplicity down to
projected separations of ≲7 AU, typically with sufficient contrast to
identify any stellar companion outside this limit. For systems with
separations of ≳500 AU, we consider the binary secondary
independently as long as it falls within the spectral type range of
interest.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 78 156 Circumstellar disk census of Taurus-Auriga
refs.dat 62 35 References
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See also:
J/ApJ/731/8 : Multiple star formation in Taurus-Auriga (Kraus+, 2011)
J/ApJ/724/835 : The Spitzer c2d survey of WTTSs. III. (Wahhaj+, 2010)
J/ApJ/720/480 : DISCS. I. Taurus protoplanetary disk data (Oberg+, 2010)
J/ApJ/703/1511 : Wide binaries in Taurus and Upper Sco (Kraus+, 2009)
J/PASJ/60/209 : Faint companions around YSOs in TMC (Itoh+, 2008)
J/ApJ/647/1180 : Infrared photometry of Taurus SFR (Luhman+, 2006)
J/ApJ/645/676 : Spatial distribution of brown dwarfs in Taurus (Luhman+, 2006)
J/ApJ/636/932 : Mid-infrared survey of T Tauri stars (McCabe+, 2006)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 15 A15 --- Name Object name
17 I1 h RAh Hour of Right Ascension (J2000)
19- 20 I2 min RAm Minute of Right Ascension (J2000)
22- 26 F5.2 s RAs Second of Right Ascension (J2000)
28 A1 --- DE- Sign of the Declination (J2000)
29- 30 I2 deg DEd Degree of Declination (J2000)
32- 33 I2 arcmin DEm Arcminute of Declination (J2000)
35- 38 F4.1 arcsec DEs Arcsecond of Declination (J2000)
40- 44 F5.1 AU Sep ? Binary Seperation
46 A1 --- f_Sep [s] Indicates a single system in Sep
48 A1 --- Acc? [Y/N] Accretion Present?
50- 51 I2 --- r_Acc? ? Reference for Acc? (see refs.dat file)
53 A1 --- E8? [Y/N] Excess of 2-8um emission?
55- 56 I2 --- r_E8? ? Reference for E8? (see refs.dat file)
58 A1 --- E30? [Y/N] Excess of 10-30um emission?
60- 61 I2 --- r_E30? ? Reference for E30? (see refs.dat file)
63 A1 --- E200? [Y/N] Excess of 30-200um emission?
65 I1 --- r_E200? ? Reference for E200? (see refs.dat file)
67 A1 --- E3mm? [Y/N] Excess of 1-3mm emission?
69- 70 I2 --- r_E3mm? ? Reference for E3? (see refs.dat file)
72- 78 A7 --- Disk [Y/N/Class I] Disk Present? (1)
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Note (1): "Class I" systems have near-infrared excesses, but since the
emission can't be distinguished as coming from the envelope or a disk,
we mark those systems here and omit them from our analysis.
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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- 2 I2 --- Ref Reference code
4- 22 A19 --- BibCode Bibcode
24- 42 A19 --- Aut Author's name(s)
44- 62 A19 --- Comm Catalog's reference
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 28-Jun-2013