J/ApJ/696/L84 Primordial circumstellar disks in binary systems (Cieza+, 2009)
Primordial circumstellar disks in binary systems: evidence for reduced
lifetimes.
Cieza L.A., Padgett D.L., Allen L.E., McCabe C.E., Brooke T.Y., Carey S.J.,
Chapman N.L., Fukagawa M., Huard T.L., Noriga-Crespo A., Peterson D.E.,
Rebull L.M.
<Astrophys. J., 696, L84-L88 (2009)>
=2009ApJ...696L..84C 2009ApJ...696L..84C
ADC_Keywords: Molecular clouds ; Stars, pre-main sequence ;
Photometry, infrared ; Surveys ; Stars, double and multiple
Keywords: binaries: general - circumstellar matter - infrared: stars -
planetary systems: protoplanetary disks - stars: pre-main sequence
Abstract:
We combine the results from several multiplicity surveys of
pre-main-sequence stars located in four nearby star-forming regions
with Spitzer data from three different Legacy Projects. This allows us
to construct a sample of 349 targets, including 125 binaries, which we
use to to investigate the effect of companions on the evolution of
circumstellar disks. We find that the distribution of projected
separations of systems with Spitzer excesses is significantly
different (P∼2.4e-5, according to the K-S test for binaries with
separations less than 400AU) from that of systems lacking evidence for
a disk. As expected, systems with projected separations less than 40AU
are half as likely to retain at least one disk than are systems with
projected separations in the 40-400AU range. These results represent
the first statistically significant evidence for a correlation between
binary separation and the presence of an inner disk (r∼1AU). Several
factors (e.g., the incompleteness of the census of close binaries, the
use of unresolved disk indicators, and projection effects) have
previously masked this correlation in smaller samples. We discuss the
implications of our findings for circumstellar disk lifetimes and the
formation of planets in multiple systems.
Description:
We collected projected binary separations from near-IR multiplicity
surveys of PMS stars located in the following nearby (d<160pc)
star-forming regions: Ophiuchus (Simon et al. 1995ApJ...443..625S 1995ApJ...443..625S;
Prato 2007ApJ...657..338P 2007ApJ...657..338P; Ratzka et al. 2005A&A...437..611R 2005A&A...437..611R), Taurus
(Leinert et al. 1993A&A...278..129L 1993A&A...278..129L; Simon et al. 1995ApJ...443..625S 1995ApJ...443..625S;
Kohler & Leinert 1998A&A...331..977K 1998A&A...331..977K), Chameleon I (Lafreniere et al.
2008ApJ...683..844L 2008ApJ...683..844L), and Corona Australis (Kohler et al.
2008A&A...488..997K 2008A&A...488..997K). Most of the surveys were performed using speckle
imaging.
Using their Two Micron All Sky Survey coordinates and a 2" matching
radius, we searched for the Spitzer fluxes of all the targets from the
surveys discussed above in the catalogs produced by the Cores to Disks
(Evans et al. 2003PASP..115..965E 2003PASP..115..965E), Taurus (Padgett et al.
2006AAS...209.3016P 2006AAS...209.3016P), and Gould Belt (Allen et al.
2007AAS...211.8919A 2007AAS...211.8919A) Legacy Projects.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 125 349 Multiplicity and Spitzer data
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See also:
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
J/A+A/515/A75 : Low-mass population in ρ Oph cloud (Alves de Oliveira+,
2010)
J/PASJ/60/209 : Faint companions around YSOs in TMC (Itoh+, 2008)
J/ApJ/684/654 : Low-mass members of Chamaeleon I (Luhman+, 2008)
J/ApJ/675/1375 : IRAC/MIPS photometry in Cha I (Luhman+, 2008)
J/A+A/488/987 : Near-infrared survey of R CrA cloud (Haas+, 2008)
J/A+A/446/485 : New very low-mass members in Taurus (Guieu+, 2006)
J/A+A/452/245 : Near-IR photometry of PMS stars in rho Oph (Natta+, 2006)
J/ApJ/647/1180 : Infrared photometry of Taurus SFR (Luhman+, 2006)
J/ApJ/630/381 : Mid-IR imaging in ρ Oph (Barsony+, 2005)
J/AJ/121/2673 : 3µm survey of the Chamaeleon I dark cloud (Kenyon+, 2001)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 16 A16 --- Name Object Name
18- 25 F8.4 deg RAdeg Right Ascension in decimal degrees (J2000)
27- 34 F8.4 deg DEdeg Declination in decimal degrees (J2000)
36- 40 A5 --- Region Star-forming region (Cha_I, CrA, Oph or Tau)
42- 47 F6.3 arcsec Sep ? Angular separation (if binary)
49- 53 A5 --- Ref Reference for multiplicity survey (1)
55- 62 E8.2 mJy F3.6um Spitzer/IRAC 3.6 micron flux
64- 71 E8.2 mJy e_F3.6um Error in 3.6 micron flux
73- 80 E8.2 mJy F4.5um Spitzer/IRAC 4.5 micron flux
82- 89 E8.2 mJy e_F4.5um Error in 4.5 micron flux
91- 98 E8.2 mJy F5.8um Spitzer/IRAC 5.8 micron flux
100-107 E8.2 mJy e_F5.8um Error in 5.8 micron flux
109-116 E8.2 mJy F8.0um Spitzer/IRAC 5.8 micron flux
118-125 E8.2 mJy e_F8.0um Error in 5.8 micron flux
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Note (1): References as follows:
1 = Leinert et al. 1993A&A...278..129L 1993A&A...278..129L
2 = Simon et al. 1995ApJ...450..824S 1995ApJ...450..824S
3 = Lafreniere et al. 2008ApJ...683..844L 2008ApJ...683..844L
4 = Prato et al. 2007ApJ...657..338P 2007ApJ...657..338P
5 = Ratzka et al. 2005A&A...437..611R 2005A&A...437..611R
6 = Koheler et al. 2008A&A...488..997K 2008A&A...488..997K
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 02-May-2011