J/ApJ/925/39 The VANDAM survey of Orion protostars. V. Mult. (Tobin+, 2022)
The VLA/ALMA Nascent Disk And Multiplicity (VANDAM) survey of Orion protostars.
V. A characterization of protostellar multiplicity.
Tobin J.J., Offner S.S.R., Kratter K.M., Megeath S.T., Sheehan P.D.,
Looney L.W., Diaz-Rodriguez A.K., Osorio M., Anglada G., Sadavoy S.I.,
Furlan E., Segura-Cox D., Karnath N., van 't Hoff M.L.R.,
van Dishoeck E.F., Li Z.-Y., Sharma R., Stutz A.M., Tychoniec L.
<Astrophys. J., 925, 39 (2022)>
=2022ApJ...925...39T 2022ApJ...925...39T
ADC_Keywords: YSOs; Molecular clouds; Millimetric/submm sources;
Stars, double and multiple; Stars, distances
Keywords: Protostars ; Young stellar objects ; Radio interferometry ;
Multiple stars
Abstract:
We characterize protostellar multiplicity in the Orion molecular
clouds using Atacama Large Millimeter/submillimeter Array 0.87mm and
Very Large Array 9mm continuum surveys toward 328 protostars. These
observations are sensitive to projected spatial separations as small
as ∼20au, and we consider source separations up to 104au as potential
companions. The overall multiplicity fraction (MF) and companion
fraction (CF) for the Orion protostars are 0.30±0.03 and
0.44±0.03, respectively, considering separations from 20 to 104au.
The MFs and CFs are corrected for potential contamination by
unassociated young stars using a probabilistic scheme based on the
surface density of young stars around each protostar. The companion
separation distribution as a whole is double peaked and inconsistent
with the separation distribution of solar-type field stars, while the
separation distribution of Flat Spectrum protostars is consistent
solar-type field stars. The multiplicity statistics and companion
separation distributions of the Perseus star-forming region are
consistent with those of Orion. Based on the observed peaks in the
Class 0 separations at ∼100au and ∼103au, we argue that multiples with
separations <500au are likely produced by both disk fragmentation and
turbulent fragmentation with migration, and those at ≥103au result
primarily from turbulent fragmentation. We also find that MFs/CFs may
rise from Class 0 to Flat Spectrum protostars between 100 and 103au in
regions of high young stellar object density. This finding may be
evidence for the migration of companions from >103au to <103au, and
that some companions between 103 and 104au must be (or become) unbound.
Description:
The ALMA observations were conducted between 2016 and 2017 at 0.87mm
toward 328 protostars in Orion and have a typical angular resolution
of 0.1". The VLA observations were also conducted between 2016 and
2017 at 9.1mm toward 148 systems with a typical angular resolution of
0.08". The observations and data reduction were described in Paper I
(Tobin+ 2019ApJ...886....6T 2019ApJ...886....6T).
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 110 432 Orion catalog
table2.dat 91 106 Perseus catalog
table3.dat 262 157 Orion protostar pairings
table4.dat 123 42 Perseus protostar pairings
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See also:
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
VII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006)
J/AJ/134/2272 : Visual binaries in Orion Nebula Cluster (Reipurth+, 2007)
J/ApJ/675/491 : Lynds 988e JHKs and IRAC photometry (Allen+, 2008)
J/ApJ/692/973 : Protostars in Perseus, Serpens and Ophiuchus (Enoch+, 2009)
J/ApJS/190/1 : A survey of stellar families (Raghavan+, 2010)
J/ApJ/731/8 : Multiple star formation in Taurus-Auriga (Kraus+, 2011)
J/ApJ/751/115 : Millimeter em. from Taurus binary systems (Harris+, 2012)
J/AJ/144/192 : Spitzer survey of Orion A and B. I. YSOs (Megeath+, 2012)
J/ApJ/764/114 : BVRI photometry of stars in Orion A (Hsu+, 2013)
J/other/Nat/493.378 : LRL 54361 Spitzer light curves (Muzerolle+, 2013)
J/ApJ/767/36 : APEX observations of HOPS protostars (Stutz+, 2013)
J/MNRAS/449/2618 : M-dwarfs in Multiples (MinMs) survey. I. (Ward-Duong+, 2015)
J/ApJ/828/46 : ALMA survey of Lupus protopl. disks. I. (Ansdell+, 2016)
J/ApJS/224/5 : Herschel Orion Protostar Survey (HOPS): SEDs (Furlan+, 2016)
J/ApJ/821/52 : NIR survey of Spitzer YSOs in Orion MoC (Kounkel+, 2016)
J/A+A/587/A47 : SMA 1.3mm image of OMC 1 North (Teixeira+, 2016)
J/ApJ/818/73 : Study of protostars in the Perseus MoC (Tobin+, 2016)
J/ApJ/846/144 : Virial analysis of the dense cores in Orion A (Kirk+, 2017)
J/ApJ/834/142 : Gould's Belt Distances Survey. II. OMC (Kounkel+, 2017)
J/MNRAS/469/3881 : Embedded binaries and their dense cores (Sadavoy+, 2017)
J/AJ/156/84 : APOGEE-2 survey of Orion Complex. II. (Kounkel+, 2018)
J/ApJ/865/73 : GOBELINS. V. Kinematics of Perseus (Ortiz-Leon+, 2018)
J/ApJ/872/158 : Class II sources in Taurus with ALMA (Akeson+, 2019)
J/AJ/157/196 : Close companions around young stars (Kounkel+, 2019)
J/AJ/157/216 : Stellar mult. rate of M dwarfs within 25pc (Winters+, 2019)
J/ApJ/890/130 : VANDAM survey of Orion protostars. II. (Tobin+, 2020)
J/A+A/640/A27 : Protoplanetary disk masses in NGC 2024 (van Terwisga+, 2020)
J/ApJ/911/153 : HST NIR images of protostars in Orion (Habel+, 2021)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 21 A21 --- ID Source identifier
23- 43 A21 --- Main Main Source identifier
45- 46 I2 h RAh [5/5] Hour of Right Ascension (J2000)
48- 49 I2 min RAm [33/54] Minute of Right Ascension (J2000)
51- 56 F6.3 s RAs Second of Right Ascension (J2000)
58 A1 --- DE- [±] Sign of the Declination (J2000)
59- 60 I2 deg DEd [0/8] Degree of Declination (J2000)
62- 63 I2 arcmin DEm Arcminute of Declination (J2000)
65- 69 F5.2 arcsec DEs Arcsecond of Declination (J2000)
71- 77 F7.2 Lsun LBol [0.02/1405]?=-99 Bolometric luminosity
79- 84 F6.2 K TBol [23/914]?=-99 Bolometric temperature
86- 97 A12 --- Class Protostar classification (1)
99- 104 F6.1 pc-2 sigYSO [0.7/2789] Local YSO surface density
106- 110 F5.1 pc Dist [351/441.1] Distance
--------------------------------------------------------------------------------
Note (1): Classification as follows:
0 = Class 0; 142 occurrences
I = Class I; 132 occurrences
Flat = Flat spectrum; 120 occurrences
Unclassified = 38 occurrences
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Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 15 A15 --- ID Source identifier
17- 31 A15 --- Main Main Source identifier
33- 34 I2 h RAh [3] Hour of Right Ascension (J2000)
36- 37 I2 min RAm [25/47] Minute of Right Ascension (J2000)
39- 44 F6.3 s RAs Second of Right Ascension (J2000)
46 A1 --- DE- [±] Sign of the Declination (J2000)
47- 48 I2 deg DEd [30/32] Degree of Declination (J2000)
50- 51 I2 arcmin DEm Arcminute of Declination (J2000)
53- 57 F5.2 arcsec DEs Arcsecond of Declination (J2000)
59- 64 F6.2 Lsun LBol [0.07/55.3]?=-99 Bolometric luminosity
66- 72 F7.2 K TBol [14.7/5000]?=-99 Bolometric temperature
74- 85 A12 --- Class Classification (1)
87- 91 F5.1 pc-2 sigYSO [0.6/668.5] Local YSO surface density
--------------------------------------------------------------------------------
Note (1): Classification as follows:
0 = Class 0; 55 occurrences
I = Class I; 37 occurrences
II = Class II; 12 occurrences
Unclassified = 2 occurrences
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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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1-159 A159 --- Pair Source pair identifiers
161-166 F6.3 arcsec ASep [0.05/23.8] Angular separation
168-172 F5.3 arcsec e_ASep [0.001/0.04] Uncertainty in ASep
174-179 F6.1 AU PSep [21.8/10000] Physical separation
181-184 F4.1 AU e_PSep [0.2/16] Uncertainty in PSep
186-190 F5.2 [-] log0.87FR [-2.1/-0.01]? log F1/F2 flux ratio
at 0.87mm (1)
192-195 F4.2 [-] e_log0.87FR [0/0.5]? Uncertainty in log0.87FR
197-201 F5.2 [-] log9FR [-1.6/0]? log F1/F2 flux ratio at 9mm (1)
203-206 F4.2 [-] e_log9FR [0.01/0.7]? Uncertainty in log9FR
208-211 F4.2 --- Prob [0.36/1]? Probability (2)
213-262 A50 --- Class Classifications (3)
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Note (1): Flux ratios are only provided for pairings of single components.
Note (2): Corresponds to the probability of the pairing being a true, bound
pair and not a line of sight association, based on the YSO surface
density. The overall probability of each member may be lower given
the multiplicative nature of companion probabilities when pairing
two binary (or higher order systems) together.
Note (3): Classes are provided in abbreviated form:
C0 = Class 0;
CI = Class I;
FS = Flat Spectrum;
CII = Class II.
N = does not have a classification.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 56 A56 --- Pair Source pair identifiers
58- 63 F6.3 arcsec ASep [0.08/32] Angular separation
65- 69 F5.3 arcsec e_ASep [0.001/0.04] Uncertainty in ASep
71- 76 F6.1 AU PSep [24/9586] Physical separation
78- 81 F4.1 AU e_PSep [0.3/12] Uncertainty in PSep
83- 87 F5.2 [-] log9FR [-1.1/-0.02]? log F1/F2 flux ratio at 9mm (1)
89- 92 F4.2 [-] e_log9FR [0.02/0.2]? Uncertainty in log9FR
94- 97 F4.2 --- Prob [0.39/1]? Probability (2)
99-123 A25 --- Class Classifications (3)
--------------------------------------------------------------------------------
Note (1): Flux ratios are only provided for pairings of single components.
Note (2): Corresponds to the probability of the pairing being a true, bound
pair and not a line of sight association, based on the YSO surface
density. The overall probability of each member may be lower given
the multiplicative nature of companion probabilities when pairing
two binary (or higher order systems) together.
Note (3): Classes are provided in abbreviated form:
C0 = Class 0;
CI = Class I;
FS = Flat Spectrum;
CII = Class II.
N = does not have a classification.
--------------------------------------------------------------------------------
History:
From electronic version of the journal
References:
Tobin et al. Paper I. 2019ApJ...886....6T 2019ApJ...886....6T
Tobin et al. Paper II. 2020ApJ...890..130T 2020ApJ...890..130T Cat. J/ApJ/890/130
Sheehan et al. Paper III. 2020ApJ...902..141S 2020ApJ...902..141S
Tobin et al. Paper IV. 2020ApJ...905..162T 2020ApJ...905..162T
Tobin et al. Paper V. 2022ApJ...925...39T 2022ApJ...925...39T This catalog
Sheehan et al. Paper VI. 2022ApJ...929...76S 2022ApJ...929...76S Cat. J/ApJ/929/76
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 29-Aug-2023