J/A+A/665/A148 Tarantula Massive Binary Monitoring. VI. (Shenar+, 2022)
The Tarantula Massive Binary Monitoring.
VI: Characterisation of hidden companions in 51 single-lined O-type binaries.
A flat mass-ratio distribution and black-hole binary candidates.
Shenar T., Sana H., Mahy L., Maiz Apellaniz J., Crowther P.A., Gromadzki M.,
Herrero A., Langer N., Marchant P., Schneider F.R.N., Sen K., Soszynski I.,
Toonen S.
<Astron. Astrophys. 665, A148 (2022)>
=2022A&A...665A.148S 2022A&A...665A.148S (SIMBAD/NED BibCode)
ADC_Keywords: Magellanic Clouds ; Stars, variable ; Binaries, spectroscopic ;
Spectra, optical
Keywords: binaries: spectroscopic - stars: black holes - Magellanic Clouds -
stars: massive - stars: evolution
Abstract:
We aim to hunt for massive binaries hosting a black hole companion
(OB+BH) and establish the natal mass-ratio distribution of massive
stars at the subsolar metallicity environment of the Large Magellanic
Cloud (LMC). To this end, we use the shift-and-add grid disentangling
technique to characterize the hidden companions in 51 SB1 O-type and
evolved B-type binaries in the LMC monitored in the framework of the
Tarantula Massive Binary Monitoring (TMBM). We find that, out of the
51 SB1 systems, 43 (84%) are found to have non-degenerate stellar
companions, of which 28 are confident detections, and 15 are less
certain (SB1: or SB2:). Of these 43 targets, one is found to be a
triple (VFTS 64), and two are found to be quadruples (VFTS 120, 702).
The remaining eight targets (16%) retain an SB1 classification. Aside
from the unambiguous case of VFTS 243, analysed in detailed in a
separate paper, we identify two additional OB+BH candidates: VFTS 514
and VFTS 779. Additional black holes may be present in the sample but
at a lower probability. Our study firmly establishes a virtually flat
natal mass-ratio distribution for O-type stars at LMC metallicity,
covering the entire mass-ratio range (0.05<q<1) and periods in the
range 0<logP<3[d]. The nature of the OB+BH candidates should be
verified through future monitoring, but the frequency of OB+BH
candidates is generally in line with recent predictions at LMC
metallicity.
Description:
We characterised the nature of the hidden companions
in 51 SB1 O-type and evolved B-type binaries identified in the
framework of the Tarantula Massive Binary Monitoring (TMBM) campaign
(Almeida et al., 2017, Cat. J/A+A/598/A84). We implemented the
shift-and-add disentangling algorithm to separate the component
spectra and establish the RV amplitudes of the two components,
whenever possible.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 155 51 VFTS identifiers, previous spectral types, new
spectral types from our study, and orbital periods
table2.dat 169 56 VFTS identifiers, new spectral types from our study,
orbital parameters, mass ratios, probability of the
system to host a black hole assuming the companion
is a compact object, estimated secondary mass, and
individual comments
tabled1.dat 47 56 Projected rotational velocities and minimum
inclinations
list.dat 165 84 List of spectra
sp/* . 84 Individual spectra
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See also:
J/A+A/598/A84 : OB-type spectroscopic binaries (Almeida+, 2017)
J/A+A/598/A85 : Disentangled spectra of R145 (Shenar+, 2017)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- VFTS VFTS identifier
5- 21 A17 --- SpTypeOld Old spectral type (from Almeida et al.,
2017A&A...598A..84A 2017A&A...598A..84A, Cat. J/A+A/598/A84)
23- 53 A31 --- SpTypeNew New spectral type (this work)
55- 66 F12.7 d P Orbital period
68- 76 F9.7 d e_P Orbital period error
78- 79 I2 --- Nepochs Number of spectra used
81- 83 I3 --- S/Nmean Mean signal-to-noise of spectra
85- 93 F9.6 Msun f Mass function
95-102 F8.6 Msun e_f Mass function error
104-107 F4.2 --- f1/ftot(V) Primary light contribution in visual
109-113 I5 K Teff1 Primary effective temperature
115-118 F4.2 [10-7W] logL1 Primary luminosity (in log(erg/s))
120-121 I2 Msun M1SpT Primary mass from spectral type calibration
123-124 I2 Msun e_M1SpT Primary mass from spectral type calibration
error
126-127 I2 Msun M1ev Primary evolutionary mass
129-130 I2 Msun E_M1ev Primary evolutionary mass error plus
132-133 I2 Msun e_M1ev Primary evolutionary mass error minus
135-138 F4.1 Msun M2min Secondary minimum mass
140-143 F4.1 Msun E_M2min Secondary minimum mass error plus
145-148 F4.1 Msun e_M2min Secondary minimum mass error minus
150 A1 --- l_logLX Limit flag on logLX
151-155 F5.2 [10-7W] logLX ?=- X-ray luminosity (in log(erg/s))
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- VFTS VFTS identifier
4 A1 --- m_VFTS [AB] Multiplicity index on VFTS (G1)
6- 36 A31 --- SpType New spectral type (this work)
38- 49 F12.7 d P ?=- Orbital period
51- 59 F9.7 d e_P ?=- Orbital period error
61- 69 F9.3 d T0 ?=- Time of periastron in JD-2400000
71- 76 F6.3 d e_T0 ?=- Time of periastron error
78- 82 F5.3 --- e ?=- Eccentricity
84- 88 F5.3 --- e_e ?=- Eccentricity error
90- 96 F7.2 deg omega ?=- Argument of periastron
98-102 F5.2 deg e_omega ?=- Argument of periastron error
104-108 F5.1 km/s K1 ?=- Primary radial velocity semi-amplitude
110-113 F4.1 km/s e_K1 ?=- Primary radial velocity semi-amplitude
error
115-119 F5.1 km/s K2 ?=- Secondary radial velocity semi-amplitude
121-124 F4.1 km/s e_K2 ?=- Secondary radial velocity semi-amplitude
126-129 F4.2 --- q ?=- Mass ratio secondary to primary
131-134 F4.2 --- e_q ?=- Mass ratio secondary to primary error
137-139 I3 % P(BH|co) ?=- Black hole probability assuming
companion is compact
140 A1 --- u_P(BH|co) [)] Uncertainty flag on P(BH|co) for values
for uncertain SB2 systems (SB2:)
142-145 F4.1 Msun M2 ?=- Secondary mass
147-150 F4.1 Msun e_M2 ?=- Secondary mass error
152-169 A18 --- Com Comments
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Byte-by-byte Description of file: tabled1.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- VFTS VFTS identifier
4 A1 --- m_VFTS [AB] Multiplicity index on VFTS (G1)
6- 36 A31 --- SpType New spectral type (this work)
38- 40 I3 km/s vsini1 ?=- Primary projected rotational velocity
42- 44 I3 km/s vsini2 ?=- Secondary projected rotational velocity
46- 47 I2 deg icrit ?=- Minimum inclination
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Byte-by-byte Description of file: list.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- --- [VFTS]
5- 7 I3 --- VFTS VFTS identifier
9 A1 --- m_VFTS [ABCD] Multiplicity index on VFTS (G1)
11- 14 F4.2 % l2 ? Secondary light contribution
16- 29 F14.10 km/s K1 ? Primary radial velocity semi-amplitude
31- 49 F19.15 km/s K2 Secondary radial velocity semi-amplitude
50- 62 F13.9 km/s K3 ? Third radial velocity semi-amplitude
64- 76 F13.9 km/s K4 ? Fourth radial velocity semi-amplitude
78-165 A88 --- FileName Name of the spectrum file in subdirectory sp
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Byte-by-byte Description of file: sp/*
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Bytes Format Units Label Explanations
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1- 24 E24.19 0.1nm lambda Wavelength
26- 50 E25.19 --- NFlux Normalised flux
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Global notes:
Note (G1): Note on triples and quaduples.
For 64, A is the tertiary (identified as primary originally), and C + D are
the components of the inner binary.
For 120, A + B are the components of one binary, and C + D are the
components of the other binary.
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Acknowledgements:
Tomer Shenar, T.Shenar(at)uva.nl
References:
Almeida et al., Paper I 2017A&A...598A..84A 2017A&A...598A..84A, Cat. J/A+A/596/A84
Shenar et al., Paper II 2017A&A...598A..85S 2017A&A...598A..85S, Cat. J/A+A/598/A85
Mahy et al., Paper III 2020A&A...634A.118M 2020A&A...634A.118M
Mahy et al., Paper IV 2020A&A...634A.119M 2020A&A...634A.119M
Shenar et al., Paper V 2021A&A...650A.147S 2021A&A...650A.147S
(End) Patricia Vannier [CDS] 28-Jul-2022