J/ApJ/813/83 Multiple star formation in Ophiuchus (Cheetham+, 2015)
Mapping the shores of the brown dwarf desert.
IV. Ophiuchus.
Cheetham A.C., Kraus A.L., Ireland M.J., Cieza L., Rizzuto A.C.,
Tuthill P.G.
<Astrophys. J., 813, 83 (2015)>
=2015ApJ...813...83C 2015ApJ...813...83C (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Infrared sources ; Spectral types ;
Stars, masses ; Stars, pre-main sequence
Keywords: binaries: general; brown dwarfs; stars: low-mass;
stars: pre-main sequence
Abstract:
We conduct a multiplicity survey of members of the ρ Ophiuchus
cloud complex with high-resolution imaging to characterize the
multiple-star population of this nearby star-forming region and
investigate the relation between stellar multiplicity and star and
planet formation. Our aperture masking survey reveals the presence of
five new stellar companions beyond the reach of previous studies, but
does not result in the detection of any new substellar companions. We
find that 43±6% of the 114 stars in our survey have stellar-mass
companions between 1.3 and 780 AU, while 7-5+8% host brown dwarf
companions in the same interval. By combining this information with
knowledge of disk-hosting stars, we show that the presence of a close
binary companion (separation <40AU) significantly influences the
lifetime of protoplanetary disks, a phenomenon previously seen in
older star-forming regions. At the ∼1-2Myr age of our Ophiuchus
members ∼2/3 of close binary systems have lost their disks, compared
to only ∼30% of single stars and wide binaries. This has a significant
impact on the formation of giant planets, which are expected to
require much longer than 1 Myr to form via core accretion and thus
planets formed via this pathway should be rare in close binary
systems.
Description:
The targets were observed over several years using the Keck NIRC2
instrument with its visible AO system, from 2008 Jun through 2013 Aug.
One dataset (2013 Mar 09-10) was also taken with the VLT NACO
instrument and IR AO system, allowing targets with bright IR
magnitudes to be observed. The observing strategy for our observations
was similar to that used in Kraus et al. (2008ApJ...679..762K 2008ApJ...679..762K).
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 82 114 Survey sample
table3.dat 76 105 Non detections
table4.dat 91 14 Companions identified with aperture masking
--------------------------------------------------------------------------------
See also:
I/297 : NOMAD Catalog (Zacharias+ 2005)
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
J/A+A/581/A30 : Herschel maps of ρ Oph (Rebollido+, 2015)
J/ApJ/745/19 : Binary systems in Taurus-Auriga (Kraus+, 2012)
J/ApJ/744/134 : SONYC new brown dwarfs in ρ Oph (Muzic+, 2012)
J/AJ/142/140 : Optical spectroscopy of ρ Oph stars. II. (Erickson+, 2011)
J/ApJ/731/8 : Pap II-Multiple star formation in Taurus-Auriga (Kraus+, 2011)
J/ApJS/190/1 : A survey of stellar families (Raghavan+, 2010)
J/ApJ/712/925 : Transition circumstellar disks in Ophiuchus (Cieza+, 2010)
J/ApJ/709/L114 : Protoplanetary disks in PMS binaries (Duchene, 2010)
J/ApJ/703/1511 : Wide binaries in Taurus and Upper Sco (Kraus+, 2009)
J/ApJ/696/L84 : Primordial circumstellar disks in binary syst. (Cieza+, 2009)
J/ApJS/181/62 : Survey of young solar analogs (Metchev+, 2009)
J/A+A/485/155 : HK photometry of rho Oph PMS stars (Alves de Oliveira+, 2008)
J/ApJ/670/1367 : Gemini Deep Planet Survey (Lafreniere+, 2007)
J/ApJ/662/413 : Wide multiplicity in 3 associations with 2MASS (Kraus+, 2007)
J/A+A/460/695 : Search for Associations Containing Young stars (Torres+, 2006)
J/A+A/458/461 : Binary stars in the Orion Nebula Cluster (Koehler+, 2006)
J/A+A/452/245 : Near-IR photometry of PMS stars in rho Oph (Natta+, 2006)
J/ApJ/640/1051 : 25pc sample of Sun-like stars (Grether+, 2006)
J/ApJ/630/381 : Mid-IR imaging in ρ Oph (Barsony+, 2005)
J/AJ/130/1733 : Optical spectroscopy of ρ Oph stars (Wilking+, 2005)
J/AJ/126/1526 : IR photometry of ultracool dwarfs (Bouy+, 2003)
J/ApJ/566/993 : rho Oph (Lynds 1688) cluster NICMOS imaging (Allen+, 2002)
J/A+A/372/173 : ISOCAM obs. of the rho Ophiuchi cloud (Bontemps+, 2001)
J/A+A/356/541 : T Tauri stars in the Sco-Cen OB association (Koehler+, 2000)
J/A+A/337/403 : Low-mass stars evolutionary models (Baraffe+ 1998)
J/A+A/333/619 : Upper Scorpius OB association Lithium survey (Preibisch+ 1998)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 24 A24 --- Name Target Name
26- 27 I2 h RAh [16] Hour of Right Ascension (J2000)
29- 30 I2 min RAm [20/36] Minute of Right Ascension (J2000)
32- 37 F6.3 s RAs Second of Right Ascension (J2000)
39 A1 --- DE- [-] Sign of the Declination (J2000)
40- 41 I2 deg DEd [23/26] Degree of Declination (J2000)
43- 44 I2 arcmin DEm Arcminute of Declination (J2000)
46- 50 F5.2 arcsec DEs Arcsecond of Declination (J2000)
52- 56 A5 --- SpT Adopted MK Spectral Type
58- 62 F5.2 Msun Mass [0.2/11] Estimated mass following Kraus &
Hillenbrand (2007, J/ApJ/662/413)
64- 68 F5.2 mag Rmag [6.9/20.8]? NOMAD R magnitude;
Zacharias et al. (2004, I/297)
70- 75 F6.3 mag Ksmag [4.5/10.7] 2MASS Ks magnitude;
Skrutskie et al. (2006, VII/233)
77- 78 I2 --- r_SpT Spectral Type Literature Reference (1)
80 A1 --- Disk [NY ] Evidence of a circumstellar disk?
82 A1 --- Mult [NY] Evidence of multiplicity?
--------------------------------------------------------------------------------
Note (1): Spectral type references as follows:
1= Elias (1978ApJ...224..453E 1978ApJ...224..453E)
2= Herbig & Bell (1988cels.book.....H 1988cels.book.....H)
3= Houk & Smith-Moore (1988mcts.book.....H 1988mcts.book.....H)
4= Bouvier & Appenzeller (1992A&AS...92..481B 1992A&AS...92..481B)
5= Meyer, Wilking & Zinnecker (1993AJ....105..619M 1993AJ....105..619M)
6= Martin et al. (1998MNRAS.300..733M 1998MNRAS.300..733M)
7= Preibisch et al. (1998, J/A+A/333/619)
8= Luhman and Rieke (1999ApJ...525..440L 1999ApJ...525..440L)
9= Doppmann, Jaffe & White (2003AJ....126.3043D 2003AJ....126.3043D)
10= Wilking et al. (2005, J/AJ/130/1733)
11= Torres et al. (2006, J/A+A/460/695)
12= Cieza et al. (2010, J/ApJ/712/925)
13= Erickson et al. (2011, J/AJ/142/140)
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 25 A25 --- Name Primary Target Name
27- 36 A10 "D/M/Y" Date Observation Date
38- 46 A9 --- Filter Aperture masking filter ("CH4_short", "Kp",
"Ks" or "Lp")
48- 51 F4.2 mag dm10-20 [0/4.2] Magnitude Detection limits in Filter at
separations 10-20mas
53- 56 F4.2 mag dm20-40 Magnitude Detection limits in Filter at
separations 20-40mas
58- 61 F4.2 mag dm40-80 [1.4/6.3] Magnitude Detection limits in Filter
at separations 40-80mas
63- 66 F4.2 mag dm80-160 Magnitude Detection limits in Filter at
separations 80-160mas
68- 71 F4.2 mag dm160-240 Magnitude Detection limits in Filter at
separations 160-240mas
73- 76 F4.2 mag dm240-320 [0.9/6.2] Magnitude Detection limits in Filter
at separations 240-320mas
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 24 A24 --- Name Primary Target Name
26 A1 --- New [a] a: First Observation flag
28- 37 A10 "D/M/Y" Date Observation Date
39- 47 A9 --- Filter Aperture masking filter ("CH4_short", "Kp",
or "Ks")
49- 54 F6.2 mas Sep [21.7/128.2] Secondary-Primary Separation
56- 59 F4.2 mas e_Sep [0.1/3.5] Uncertainty in Sep
61- 66 F6.2 deg PA [50.9/314.1] Secondary-Primary Position Angle
68- 71 F4.2 deg e_PA [0.09/2.2] Uncertainty in PA
73- 76 F4.2 mag dmag [0.1/3] Magnitude difference in Filter
78- 81 F4.2 mag e_dmag [0.01/0.5] Uncertainty in dmag
83- 86 F4.2 --- q [0.08/0.9] Secondary/Primary Mass Ratio
88- 91 F4.2 Msun Mass [0.1/2.4] Derived Secondary Mass
--------------------------------------------------------------------------------
History:
From electronic version of the journal
References:
Kraus et al. Paper I. Upper Sco 2008ApJ...679..762K 2008ApJ...679..762K
Kraus et al. Paper II. Taurus 2011ApJ...731....8K 2011ApJ...731....8K J/ApJ/731/8
Evans et al. Paper III. YMG 2012ApJ...744..120E 2012ApJ...744..120E
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 15-Feb-2016