J/ApJ/749/79 Transition disks. II. Southern MoC (Romero+, 2012)
The nature of transition circumstellar disks.
II. Southern molecular clouds.
Romero G.A., Schreiber M.R., Cieza L.A., Rebassa-Mansergas A., Merin B.,
Smith Castelli A.V., Allen L.E., Morrell N.
<Astrophys. J., 749, 79 (2012)>
=2012ApJ...749...79R 2012ApJ...749...79R
ADC_Keywords: Photometry, infrared ; Photometry, RI ; Spectral types ; YSOs ;
Millimetric/submm sources ; Spectroscopy
Keywords: accretion, accretion disks - binaries: general -
line: identification - protoplanetary disks - stars: pre-main sequence
Abstract:
Transition disk objects are pre-main-sequence stars with little or no
near-IR excess and significant far-IR excess, implying inner opacity
holes in their disks. Here we present a multifrequency study of
transition disk candidates located in Lupus I, III, IV, V, VI, Corona
Australis, and Scorpius. Complementing the information provided by
Spitzer with adaptive optics (AO) imaging (NaCo, VLT), submillimeter
photometry (APEX), and echelle spectroscopy (Magellan, Du Pont
Telescopes), we estimate the multiplicity, disk mass, and accretion
rate for each object in our sample in order to identify the mechanism
potentially responsible for its inner hole. We find that our
transition disks show a rich diversity in their spectral energy
distribution morphology, have disk masses ranging from ≲1 to
10MJUP, and accretion rates ranging from ≲10-11 to
10-7.7M☉/yr. Of the 17 bona fide transition disks in our
sample, three, nine, three, and two objects are consistent with giant
planet formation, grain growth, photoevaporation, and debris disks,
respectively. Two disks could be circumbinary, which offers tidal
truncation as an alternative origin of the inner hole.
Description:
We obtained high-resolution (R>20000) optical spectra for our entire
sample using two different telescopes. We observed 49 of our 60
targets with the Magellan Inamori Kyocera Echelle (MIKE) spectrograph
on the 6.5m Clay Telescope. The observations were performed on 2009
April 27-28 and 2010 June 11-13. The remaining 11 targets were
observed with the Echelle Spectrograph on the 2.5m Irenee Du Pont
Telescope. The observations were performed in 2009 May 14-16.
High spatial resolution near-IR observations of our 60 targets were
obtained with NaCo (the Nasmyth Adaptive Optics Systems (NAOS) and the
Near-IR Imager and Spectrograph (CONICA) camera at the 8.2m telescope
Yepun), which is part of the European Southern Observatory's (ESO) VLT
in Cerro Paranal, Chile. The data were acquired in service mode during
the ESO's observing period 083 (2009 April 1-September 30).
The 17 bona fide PMS stars were observed with the APEX, the 12m radio
telescope located in Llano de Chajnantor in Chile. The observations
were performed during period 083 (083.F-0162A-2009, 9.2hr) and period
085 (E-085.C-0571D-2010, 30.9hr). We used the APEX-LABOCA camera at
870um (345GHz) in service mode aiming for detections of the dust
continuum emission.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 131 43 Spectroscopically identified AGB stars
table4.dat 137 17 Transition disk sample
table5.dat 74 17 Observed properties
table6.dat 83 17 Derived properties
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See also:
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
J/A+A/551/A34 : SED information for CrA members (Sicilia-Aguilar+, 2013)
J/ApJS/194/43 : YSOs candidates and knots in CrA cloud (Peterson+, 2011)
J/ApJ/712/925 : Pap. I. Transition circumstellar disks in Oph (Cieza+, 2010)
J/ApJ/724/835 : The Spitzer c2d survey of WTTSs. III. (Wahhaj+, 2010)
J/ApJ/705/1646 : Debris disks in Upper Sco (Carpenter+, 2009)
J/ApJS/177/551 : Spitzer c2d survey of Lupus dark clouds (Merin+, 2008)
J/ApJ/658/480 : Pre-main-sequence stars in Lupus association (Makarov+, 2007)
J/AJ/121/1040 : Upper Scorpius OB association PMS members (Preibisch+, 2001)
J/A+AS/123/329 : New weak-line T Tauri stars in Lupus (Krautter+ 1997)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 --- Seq [1/43] AGB running sequence number
4- 12 F9.5 deg RAdeg [234.5/285.8] Right Ascension (J2000)
14- 22 F9.5 deg DEdeg [-42.2/-15.5] Declination (J2000)
24- 46 A23 --- SST Spitzer identifier (SSTc2d or SSTGBS with
J2000 coordinates)
48- 52 F5.2 mag Rmag [13.11/17.92] USNO-B1 R band magnitude (1)
54- 61 E8.3 mJy FJ [39.5/2230] 2MASS J band flux density (1)
63- 70 E8.3 mJy FH [80.7/4600] 2MASS H band flux density (1)
72- 79 E8.3 mJy FKs [87.3/5140] 2MASS Ks band flux density (1)
81- 88 E8.3 mJy F3.6 [47/2510] Spitzer/IRAC 3.6um band flux density (1)
90- 97 E8.3 mJy F4.5 [30/1610] Spitzer/IRAC 4.5um band flux density (1)
99-106 E8.3 mJy F5.8 [25/1410] Spitzer/IRAC 5.8um band flux density (1)
108-115 E8.3 mJy F8.0 [18/950] Spitzer/IRAC 8.0um band flux density (1)
117-124 E8.3 mJy F24 [5/319] Spitzer/MIPS 24um band flux density (1)
126-129 A4 --- Reg Star forming region (LI, LIII, LIV, LV, LVI
[Lupus], Scp [Scorpius] or Cra [Corona Australis])
131 I1 --- Ref [1/3]? Reference of previous catalog (2)
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Note (1): Detections are >7σ (i.e. the photometric uncertainties <15%).
Note (2): Reference of previous catalogs that list the object as YSOc as
follows:
1 = Merin et al (2008, Cat. J/ApJS/177/551);
2 = Spezzi et al. (2011ApJ...730...65S 2011ApJ...730...65S);
3 = Peterson et al. (2011, Cat. J/ApJS/194/43).
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 --- Seq [1/17] TD running sequence number
4- 26 A23 --- SST Spitzer identifier (SSTc2d or SSTGBS with
J2000 coordinates)
28- 34 A7 --- OName Alternative identification
36- 40 F5.2 mag R1mag [11.2/17.2] USNO-B1 first R-band magnitude
42- 46 F5.2 mag R2mag [11/17] USNO-B1 second R-band magnitude
48- 55 E8.3 mJy FJ [24.6/263] 2MASS J-band flux density (1)
57- 64 E8.3 mJy FH [31.8/344] 2MASS H-band flux density (1)
66- 73 E8.3 mJy FKs [28.8/305] 2MASS Ks-band flux density (1)
75- 82 E8.3 mJy F3.6 [19.1/177] Spitzer/IRAC 3.6um band flux density (1)
84- 91 E8.3 mJy F4.5 [13.8/141] Spitzer/IRAC 4.5um band flux density (1)
93-100 E8.3 mJy F5.8 [9.6/140] Spitzer/IRAC 5.8um band flux density (1)
102-109 E8.3 mJy F8.0 [6.5/213] Spitzer/IRAC 8.0um band flux density (1)
111-118 E8.3 mJy F24 [2.9/590] Spitzer/MIPS 24um band flux density (1)
120 A1 --- l_F70 Limit flag on F70
122-129 E8.3 mJy F70 [50/1050] Spitzer/MIPS 70um band flux density (2)
131-137 A7 --- Reg Star forming region (Lup=Lupus, Scp=Scorption,
CrA=Corona Australis)
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Note (1): All the 2MASS, IRAC, and 24um detections are ≥7σ
(i.e., the photometric uncertainties are ≲15%).
Note (2): ≥5σ detections from the c2d and Gould Belt catalogs or
5σ upper limits as described in Section 5.3.1.
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Byte-by-byte Description of file: table5.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 --- Seq [1/17] TD running sequence number
4- 12 F9.5 deg RAdeg [240.1/285.8] Right ascension (J2000)
14- 22 F9.5 deg DEdeg [-42/-19] Declination (J2000)
24- 30 A7 --- Tel Telescope used to obtain spectrum (Clay or Du Pont)
32- 36 A5 --- SpT MK spectral type from this work
38- 41 A4 --- SpTl MK spectral type from literature if any
43 A1 --- f_SpTl [f] MK type differs from ours (3)
45 I1 --- r_SpTl [2-7]? Reference for SpTl (4)
47- 50 F4.2 0.1nm W(Li) [0.2/0.6]? LiI equivalent width; in Angstroms (5)
52- 54 I3 km/s Ha [83/532] Hα velocity width
56 A1 --- l_Fmm Limit flag on Fmm (3σ upper value)
58- 62 F5.1 mJy Fmm [6.7/100] APEX (sub)millimeter flux at 870um
(345GHz)
64- 66 F3.1 mJy e_Fmm [2.2/7] 1σ uncertainty for Fmm
68- 72 F5.3 arcsec Sep [0.1/5]? Companion separation (6)
74 I1 arcsec Sep2 [3]? Separation of the widest component (6)
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Note (3):
f = The spectral type derived by us is significantly later than the
previously obtained value. We consider our estimate of M5.25 based on
a high-quality optical spectrum to be more reliable than the rather
rough guess of Merin et al. (2008, Cat. J/ApJS/177/551) derived from
optical and near-IR photometry only.
Note (4): Reference as follows:
2 = Merin et al. 2008, Cat. J/ApJS/177/551;
3 = Sicilia-Aguilar et al. 2008ApJ...687.1145S 2008ApJ...687.1145S;
4 = Krautter et al. 1997, Cat. J/A+AS/123/329;
5 = Walter et al. 1997AJ....114.1544W 1997AJ....114.1544W;
6 = Hughes et al. 1994AJ....108.1071H 1994AJ....108.1071H;
7 = Hughes et al. 1993AJ....105..571H 1993AJ....105..571H
Note (5): Blank value implies that the signal to noise in this region of
the spectrum is too low to measure the width or establish the presence
of the line.
Note (6): Sources 1, 3, 4, and 9 have been identified as binaries by WFI
observations (Merin et al. 2008, Cat. J/ApJS/177/551). The binary
nature of source 14 was discovered using speckle interferometry at
the NTT (La Silla) revealing a projected separation of 0.132±0.009"
(Kohler et al. 2008A&A...488..997K 2008A&A...488..997K). Sources 11 and 13 are triple
systems with tight binary components consistent with two equally
bright objects and a projected separation of ∼0.05".
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Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 --- Seq [1/17] TD running sequence number
4 A1 --- l_Mdot Limit flag on Mdot
6- 10 F5.1 [Msun/yr] Mdot [-11/-7.7] Log of accretion rate
12 A1 --- l_Md Limit flag on Md
14- 16 F3.1 Mjup Md [0.8/9.1] Disk mass
18- 21 I4 AU Rp [20/1000]? Projected separation
23- 25 I3 AU Rp2 [390/390]? Projected separation of the
widest component
27 A1 --- n_Rp2 [a] Triple system (7)
29- 32 F4.2 um lam(to) [2.2/8] λturnoff parameter (8)
34- 38 F5.2 --- alp.E [-2.2/0.8] Slope of the IR excess
(αexcess) (8)
40- 43 F4.1 [-] log(Ld/L*) [-3.7/-1.4] Log of fractional disk
luminosity (Ldisk/L*)
45- 48 F4.2 [Lsun] logL* [0.06/2.4] Log of stellar luminosity
50- 73 A24 --- Class Cloud partnership classification
75 A1 --- f_Class [b] Uncertain classification (7)
77- 83 A7 --- Reg Region
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Note (7): Flag as follows:
a = Objects 11 and 13 are triple systems. The distances given correspond to the
closest and widest components. For the case of object 11, the tightest
components cannot be resolved.
b = Uncertain classification due to relatively weak evidence for accretion
(targets 8 and 12) or SEDs similar to those of classical T Tauri stars of
spectral type M (targets 4, 5, 10, and 11).
Note (8): The richness of SED morphologies is defined in terms of two
parameters based on the SED shapes considering the longest wavelength
at which the observed flux is dominated by the stellar photosphere,
λturnoff, and the slope of the infrared excess,
αexcess, computed from λturnoff to 24um.
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History:
From electronic version of the journal
References:
Cieza et al. Paper I. 2010ApJ...712..925C 2010ApJ...712..925C Cat. J/ApJ/712/925
Cieza et al. Paper III. 2012ApJ...750..157C 2012ApJ...750..157C
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 14-Nov-2013