J/ApJ/790/158 Candidate halo wide binaries (Allen+, 2014)
An improved catalog of halo wide binary candidates.
Allen C., Monroy-Rodriguez M.A.
<Astrophys. J., 790, 158 (2014)>
=2014ApJ...790..158A 2014ApJ...790..158A (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Stars, population II ;
Stars, subdwarf ; Stars, halo
Keywords: binaries: visual - catalogs - Galaxy: halo - stars: Population II -
subdwarfs
Abstract:
We present an improved catalog of halo wide binaries compiled from an
extensive literature search. Most of our binaries stem from the common
proper motion binary catalogs by Allen et al. (2000, J/A+A/356/529)
and Chaname & Gould (2004ApJ...601..289C 2004ApJ...601..289C), but we have also included
binaries from the lists of Ryan (1992AJ....104.1144R 1992AJ....104.1144R) and
Zapatero-Osorio & Martin (2004, J/A+A/419/167). All binaries were
carefully checked and their distances and systemic radial velocities
are included when available. Probable membership to the halo
population was tested by means of reduced proper motion diagrams for
251 candidate halo binaries. After eliminating obvious disk binaries,
we ended up with 211 probable halo binaries, 150 of which have radial
velocities available. We compute galactic orbits for these 150
binaries and calculate the time they spend within the galactic disk.
Considering the full sample of 251 candidate halo binaries as well as
several subsamples, we find that the distribution of angular
separations (or expected major semiaxes) follows a power law
f(a) ∼ a.-1 (Oepik's relation) up to different limits. For the 50 most
disk-like binaries, those that spend their entire lives within
z = ±500 pc, this limit is found to be 19,000 AU (0.09 pc), while for
the 50 most halo-like binaries, those that spend on average only 18%
of their lives within z = ±500 pc, the limit is 63,000 AU (0.31 pc).
In a companion paper, we employ this catalog to establish limits on
the masses of the halo massive perturbers (massive compact halo objects).
Description:
A search of the literature was conducted, looking for high-velocity,
metal-poor wide binaries, since such samples are likely to be rich in
halo stars. Most of the binaries in the new catalog stem from the
lists of Ryan (1992AJ....104.1144R 1992AJ....104.1144R), Allen et al. (2000,
J/A+A/356/529), Chaname & Gould (2004ApJ...601..289C 2004ApJ...601..289C), and
Zapatero-Osorio & Martin (2004, J/A+A/419/167). All listed data were
checked and updated when necessary. We selected the most reliable data
for the distances, metallicities, and radial velocities. All proper
motions were checked in the Simbad database and non-common proper
motion companions were eliminated (i.e., we omitted pairs with proper
motions differing by more than the published values). The catalog
includes 111 halo binaries from Allen et al. (2000, J/A+A/356/529),
110 halo binaries from Chaname & Gould (2004ApJ...601..289C 2004ApJ...601..289C), 23 from
Zapatero-Osorio & Martin (2004, J/A+A/419/167) and 7 from Ryan
(1992AJ....104.1144R 1992AJ....104.1144R), to give a total of 251 halo binary candidates.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 100 251 Improved Catalog of Candidate Halo Wide Binaries
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See also:
I/79 : Lowell Proper Motion Survey 8991 Northern Stars (Giclas 1971)
I/98 : NLTT Catalogue (Luyten, 1979)
J/A+A/356/529 : Catalogue of wide binaries (Allen+ 2000)
J/A+AS/141/491 : Chemical composition of halo and disk stars (Nissen+, 2000)
J/MNRAS/325/931 : Metal-poor subdwarfs in the Hipparcos catalog (Reid+, 2001)
J/A+A/419/167 : BVRI photometry in metal-poor binaries
(Zapatero Osorio+, 2004)
J/ApJ/762/26 : Most metal-poor stars. II. 190 Galactic halo stars
(Yong+, 2013)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- Primary NLTT number of the primary NLTT NNNNN
12- 22 A11 --- AID Alternative identification of the primary
24- 36 A13 --- Secondary Identification of the secondary
38- 41 I4 pc d Distance to the primary
43- 46 F4.1 mag VMagp V-band Absolute magnitude of the primary
48- 51 F4.1 mag VMags ? V-band Absolute magnitude of the secondary
53- 59 F7.2 arcsec s Projected angular separation (1)
61- 66 I6 AU Projected angular separation (1)
68- 72 F5.1 km/s Vpec ? Peculiar velocity of the binary (2)
74- 78 F5.1 kpc Rmax ? Apocentric distance
80- 85 I6 pc zmax ? Maximum distance from the galactic plane
87- 90 F4.2 --- e ? 3D eccentricity of the galactic orbit
92- 96 F5.3 --- td/t ? Fraction spent by the binary within the
galactic disk
98-100 A3 --- Cat Provenance of the binary (3)
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Note (1): Between the components and the expected value for the major semiaxis.
Note (2): This velocity is computed assuming a solar motion of (9, 12, 7) km/s.
The radial velocity used to compute the peculiar velocity is taken from
various sources, listed mostly in the Simbad database.
Note (3): References as follows :
A = Allen et al. 2000, J/A+A/356/529;
CG = Chaname & Gould, 2004ApJ...601..289C 2004ApJ...601..289C;
Z = Zapatero-Osorio & Martin 2004, J/A+A/419/167;
R = Ryan, 1992AJ....104.1144R 1992AJ....104.1144R
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History:
From electronic version of the journal
(End) Prepared by Tiphaine Pouvreau [CDS] 22-Mar-2017