J/AJ/155/54 TBOSS Survey. II. ALMA continuum observations (Ward-Duong+, 2018)
The Taurus Boundary of Stellar/Substellar (TBOSS) survey.
II. Disk masses from ALMA continuum observations.
Ward-Duong K., Patience J., Bulger J., van der Plas G., Menard F., Pinte C.,
Jackson A.P., Bryden G., Turner N.J., Harvey P., Hales A., De Rosa R.J.
<Astron. J., 155, 54 (2018)>
=2018AJ....155...54W 2018AJ....155...54W (SIMBAD/NED BibCode)
ADC_Keywords: Stars, brown dwarf ; Stars, pre-main sequence ; Spectral types ;
Millimetric/submm sources ; Photometry, infrared ; Stars, masses ;
Proper motions ; Effective temperatures ; Stars, diameters
Keywords: brown dwarfs - protoplanetary disks - stars: formation -
stars: low-mass - stars : pre-main sequence
Abstract:
We report 885 µm ALMA continuum flux densities for 24 Taurus members
spanning the stellar/substellar boundary with spectral types from M4
to M7.75. Of the 24 systems, 22 are detected at levels ranging from
1.0 to 55.7 mJy. The two nondetections are transition disks, though
other transition disks in the sample are detected. Converting ALMA
continuum measurements to masses using standard scaling laws and
radiative transfer modeling yields dust mass estimates ranging from
∼0.3 to 20 M⊕. The dust mass shows a declining trend with
central object mass when combined with results from submillimeter
surveys of more massive Taurus members. The substellar disks appear as
part of a continuous sequence and not a distinct population. Compared
to older Upper Sco members with similar masses across the substellar
limit, the Taurus disks are brighter and more massive. Both Taurus and
Upper Sco populations are consistent with an approximately linear
relationship in Mdust to Mstar, although derived power-law slopes
depend strongly upon choices of stellar evolutionary model and dust
temperature relation. The median disk around early-M stars in Taurus
contains a comparable amount of mass in small solids as the average
amount of heavy elements in Kepler planetary systems on short-period
orbits around M-dwarf stars, with an order of magnitude spread in disk
dust mass about the median value. Assuming a gas-to-dust ratio of
100:1, only a small number of low-mass stars and brown dwarfs have a
total disk mass amenable to giant planet formation, consistent with
the low frequency of giant planets orbiting M dwarfs.
Description:
The ALMA target sample consists of 24 Taurus low-mass stars and brown
dwarfs with spectral types of M4-M7.75. The 24 targets represent a subset
of Herschel-detected members from the 153-object Taurus Boundary of
Stellar/Substellar (TBOSS) sample (Bulger et al. 2014, J/A+A/570/A29)
that is a 99% complete sample of M4-L0 Taurus members covering Class I-III
objects. Class I and Class III detections from the TBOSS survey were
not considered for the ALMA study.
ALMA Band 7 observations were obtained for all targets in a series of
tracks executed between 2013 November and 2014 July during the Cycle 1
Early Science campaign (program ID 2012.1.00743.S). Among the available
ALMA bands, Band 7 represented the best compromise between declining
disk flux with wavelength and increasing ALMA sensitivity with wavelength.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 120 24 Sample table
table3.dat 83 22 Updated target positions from this study and
proper motions from Zacharias et al.
(2015, Cat. I/329)
table4.dat 92 24 Measured flux density values and other
parameters for the 24 targets in this sample
table8.dat 31 24 Stellar parameters used in MCFOST models
table10.dat 40 23 Genetic algorithm results with SED fitting
in MCFOST
table14.dat 111 326 Rederived stellar parameters and dust masses for
our sample
table15.dat 97 22 Dust masses
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See also:
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
I/329 : URAT1 Catalog (Zacharias+ 2015)
J/ApJ/578/914 : Low-mass stars in Taurus (Hartmann, 2002)
J/A+A/446/485 : New very low-mass members in Taurus (Guieu+, 2006)
J/ApJ/645/676 : Spatial distribution of brown dwarfs in Taurus (Luhman+, 2006)
J/ApJ/647/1180 : Infrared photometry of Taurus SFR (Luhman+, 2006)
J/ApJS/186/111 : Spitzer observations of Taurus members (Luhman+, 2010)
J/ApJS/186/259 : Taurus Spitzer survey: new candidate members (Rebull+, 2010)
J/ApJ/771/129 : Submillimetric Class II sources of Taurus (Andrews+, 2013)
J/A+A/570/A29 : TBOSS Survey I: Herschel/PACS (Bulger+, 2014)
J/ApJ/786/97 : Photospheric properties of T Tauri stars (Herczeg+, 2014)
J/ApJ/827/142 : ALMA observations of GKM stars in Upper Sco (Barenfeld+, 2016)
J/AJ/154/134 : Planetary-mass brown dwarfs in the Taurus SFR (Esplin+, 2017)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 17 A17 --- Target Target name
19- 33 A15 --- OName Other name
35- 36 I2 h RAh 2MASS Hour of Right Ascension (J2000)
38- 39 I2 min RAm 2MASS Minute of Right Ascension (J2000)
41- 46 F6.3 s RAs 2MASS Second of Right Ascension (J2000)
48 A1 --- DE- 2MASS Sign of the Declination (J2000)
49- 50 I2 deg DEd 2MASS Degree of Declination (J2000)
52- 53 I2 arcmin DEm 2MASS Arcminute of Declination (J2000)
55- 59 F5.2 arcsec DEs 2MASS Arcsecond of Declination (J2000)
61- 65 A5 --- SpType MK spectral type
67- 71 F5.1 mJy F24 [9.6/310]?=0 24µm band flux density
73- 75 I3 mJy F70 [15/445] 70µm band flux density
77 A1 --- l_F160 [<] Limit flag on F160
78- 80 I3 mJy F160 [24/639] 160µm band flux density
82-115 A34 --- Com Comment about transition disk and binary system
identification
117-120 A4 --- r_Com Reference for Comment (1)
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Note (1): Reference as follows:
1 = Currie & Sicilia-Aguilar (2011ApJ...732...24C 2011ApJ...732...24C);
2 = Cieza et al. (2012ApJ...750..157C 2012ApJ...750..157C);
3 = Bulger et al. (2014, J/A+A/570/A29);
4 = Itoh et al. (1999AJ....117.1471I 1999AJ....117.1471I);
5 = Konopacky et al. (2007ApJ...663..394K 2007ApJ...663..394K).
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Target Target name
11- 12 I2 h RAh ALMA Hour of Right Ascension (J2000)
14- 15 I2 min RAm ALMA Minute of Right Ascension (J2000)
17- 23 F7.4 s RAs ALMA Second of Right Ascension (J2000)
25 A1 --- DE- ALMA Sign of the Declination (J2000)
26- 27 I2 deg DEd ALMA Degree of Declination (J2000)
29- 30 I2 arcmin DEm ALMA Arcminute of Declination (J2000)
32- 38 F7.4 arcsec DEs ALMA Arcsecond of Declination (J2000)
40- 46 F7.3 mas oRA [44.432/344.564] Right Ascension offset from
the 2MASS J2000 coordinates
48- 53 F6.1 mas oDE [-625.2/-218.5] Declination offset from the
2MASS J2000 coordinates
55- 58 F4.1 mas/yr pmRA [-5.1/14.3] Proper motion along RA (pmRA*cosDE)
60- 63 F4.1 mas/yr e_pmRA [5.1/10] Uncertainty in pmRA
65- 69 F5.1 mas/yr pmDE [-30.5/-9.7] Proper motion along DE
71- 74 F4.1 mas/yr e_pmDE [5.1/10] Uncertainty in pmDE
76- 83 F8.3 yr Epoch [2013.108/2013.86] Epoch of observation
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Target Target name
11- 15 A5 --- SpType MK spectral type
17- 20 I4 K Teff [2696/3191] Effective temperature
22- 27 F6.3 [Lsun] logL* [-2.02/-0.701] Log stellar luminosity
29- 33 F5.3 Msun M*(B15) [0.028/0.199] Stellar mass from
Baraffe et al. (2015A&A...577A..42B 2015A&A...577A..42B)
35- 36 A2 --- l_FluxNat [< =] Limit flag on FluxNat
37- 41 F5.2 mJy FluxNat [0.27/55.65] Flux density derived from
the CASA imfit routine (natural weighting)
43- 46 F4.2 mJy e_FluxNat ? Uncertainty in FluxNat
48- 49 A2 --- l_FluxBriggs [< =] Limit flag on FluxBriggs
50- 54 F5.2 mJy FluxBriggs [0.39/48.28] Flux density derived from
the CASA imfit routine (briggs weighting)
56- 59 F4.2 mJy e_FluxBriggs [0.18/0.75]? Uncertainty in FluxBriggs
61- 62 A2 --- l_FluxUni [< =] Limit flag on FluxUni
63- 67 F5.2 mJy FluxUni [0.47/48.4] Flux density derived from
the CASA imfit routine (uniform weighting)
69- 72 F4.2 mJy e_FluxUni [0.21/0.85]? Uncertainty in FluxUni
74- 78 F5.2 mJy Flux [1.25/47.77]? Flux density derived from
the CASA uvmodelfit routine (1)
80- 83 F4.2 mJy e_Flux [0.15/0.3]? Uncertainty in Flux
85- 92 A8 --- Note Note (2)
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Note (1): The typical reduced χ2 value for the fit is ∼1.45.
Note (2): Note as follows:
SC = Sources for which self-calibration has been performed, and upper
limits denote 3x the rms in the residual image;
Non-Det. = Non detected.
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Byte-by-byte Description of file: table8.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Target Target name
11- 14 I4 K Teff [2752/3270] Effective temperature
16- 21 F6.3 [Lsun] logL* [-2.358/-0.115] Log stellar luminosity
23- 27 F5.3 Rsun R* [0.377/2.6] Stellar radius
29- 31 F3.1 mag Av [0/3] Reddening
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Byte-by-byte Description of file: table10.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Target Target name
11- 15 F5.2 Mgeo Mdust [0.1/23.31] Dust mass
17- 20 F4.1 AU H0 [10.5/25] Scale height H0 at reference radius
r0
22- 25 F4.2 AU Rin [0.01/1] Inner radius
27- 30 F4.2 --- beta [1/1.3] Flaring profile exponent β for the
disk height H(r)∼rβ
32- 36 F5.2 --- Sdens [-1.4/-0.25] Surface density index
38- 40 I3 --- chi2 [9/600] Minimum SED fit χ2
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Byte-by-byte Description of file: table14.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 25 A25 --- Target Target name
27 I1 --- r_Target [1/6] Target reference (1)
29- 30 A2 --- Flag [UL ] Upper limits calculated from sub-mm/mm
non-detection
32- 40 A9 --- Region Region identifier (Taurus, Upper Sco, Rho Oph)
42- 43 I2 Myr Age [1/10] Stellar age estimate
45- 49 A5 --- SpType Stellar MK spectral type
51- 54 I4 K Teff [2548/5294] Stellar effective temperature
estimate
56- 59 F4.2 Msun M* [0.02/2.38] Stellar mass estimate
61- 64 F4.2 Msun b_M* [0.02/2.16] Lower boundary on M*
66- 69 F4.2 Msun B_M* [0.02/2.54] Upper boundary on M*
71- 75 F5.2 [Lsun] logL* [-2.39/0.97] Log stellar luminosity estimate
77- 81 F5.2 [Lsun] b_logL* [-2.45/0.88] Lower boundary on logL*
83- 87 F5.2 [Lsun] B_logL* [-2.33/1.03] Upper boundary on logL*
89 A1 --- l_Md40 Limit flag on Md40
90- 95 F6.2 Mgeo Md40 [0.01/200.02] Dust mass at 40 AU
97 A1 --- l_Md100 Limit flag on Md100
98-103 F6.2 Mgeo Md100 [0.02/303.82] Dust mass at 100 AU
105 A1 --- l_Md200 Limit flag on Md200
106-111 F6.2 Mgeo Md200 [0.03/375.62] Dust mass at 200 AU
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Note (1): Reference as follows:
1 = This study;
2 = Andrews et al. (2013, J/ApJ/771/129);
3 = Testi et al. (2016A&A...593A.111T 2016A&A...593A.111T);
4 = Barenfeld et al. (2016, J/ApJ/827/142);
5 = van der Plas et al. (2016ApJ...819..102V 2016ApJ...819..102V);
6 = Mathews et al. (2012ApJ...745...23M 2012ApJ...745...23M).
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Byte-by-byte Description of file: table15.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Target Target name
11- 14 F4.1 K Tdust [7.8/16.7] Dust temperature (1)
16- 20 F5.2 Mgeo Mdust [0.34/23.69] Dust mass
22- 25 F4.1 K Td10 [19.9/40] Dust temperature at 10 AU
27- 30 F4.2 Mgeo Md10 [0.1/6.71] Dust mass at 10 AU
32- 35 F4.1 K Td20 [14.7/28.7] Dust temperature at 20 AU
37- 41 F5.2 Mgeo Md20 [0.16/10.24] Dust mass at 20 AU
43- 47 F5.2 K Td40 [12.99/22.43] Dust temperature at 40 AU
49- 53 F5.2 Mgeo Md40 [0.22/14.02] Dust mass at 40 AU
55- 58 F4.1 K Td60 [12.4/20.1] Dust temperature at 60 AU
60- 64 F5.2 Mgeo Md60 [0.26/16.24] Dust mass at 60 AU
66- 69 F4.1 K Td80 [11.9/18.8] Dust temperature at 80 AU
71- 75 F5.2 Mgeo Md80 [0.28/17.74] Dust mass at 80 AU
77- 80 F4.1 K Td100 [11/17.3] Dust temperature at 100 AU
82- 86 F5.2 Mgeo Md100 [0.32/20.35] Dust mass at 100 AU
88- 91 F4.1 K Td200 [9.9/15.2] Dust temperature at 200 AU
93- 97 F5.2 Mgeo Md200 [0.39/24.98] Dust mass at 200 AU
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Note (1): Tdust=25(L*/L☉)0.25.
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History:
From electronic version of the journal
References:
Bulger et al. Paper I. 2014A&A...570A..29B 2014A&A...570A..29B, Cat. J/A+A/570/A29
(End) Prepared by [AAS], Tiphaine Pouvreau [CDS] 04-Oct-2018