J/AJ/153/259 The GAMBLES extension of the SLoWPoKES catalog (Oelkers+, 2017)
Gaia Assorted Mass Binaries Long Excluded from SLoWPoKES (GAMBLES): identifying
ultra-wide binary pairs with components of diverse mass.
Oelkers R.J., Stassun K.G., Dhital S.
<Astron. J., 153, 259-259 (2017)>
=2017AJ....153..259O 2017AJ....153..259O (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Cross identifications ;
Photometry, SDSS ; Proper motions ; Stars, distances ;
Stars, masses
Keywords: binaries: visual - catalogs - methods: statistical
Abstract:
The formation and evolution of binary star systems are some of the
remaining key questions in modern astronomy. Wide binary pairs
(separations >103au) are particularly intriguing because their low
binding energies make it difficult for the stars to stay
gravitationally bound over extended timescales, and thus to probe the
dynamics of binary formation and dissolution. Our previous SLoWPoKES
catalogs, I and II, provided the largest and most complete sample of
wide-binary pairs of low masses. Here we present an extension of these
catalogs to a broad range of stellar masses: the Gaia Assorted Mass
Binaries Long Excluded from SloWPoKES (GAMBLES), comprising 8660
statistically significant wide pairs that we make available in a
living online database. Within this catalog we identify a subset of
543 long-lived (dissipation timescale >1.5Gyr) candidate binary pairs,
of assorted mass, with typical separations between 103 and 105.5
au (0.002-1.5pc), using the published distances and proper motions
from the Tycho-Gaia Astrometric Solution and Sloan Digital Sky Survey
photometry. Each pair has at most a false positive probability of
0.05; the total expectation is 2.44 false binaries in our sample.
Among these, we find 22 systems with 3 components, 1 system with 4
components, and 15 pairs consisting of at least 1 possible red giant.
We find the largest long-lived binary separation to be nearly 3.2pc;
even so, >76% of GAMBLES long-lived binaries have large binding
energies and dissipation lifetimes longer than 1.5Gyr. Finally, we
find that the distribution of binary separations is clearly bimodal,
corroborating the findings from SloWPoKES and suggesting multiple
pathways for the formation and dissipation of the widest binaries in
the Galaxy.
Description:
We identify systems previously excluded in the Sloan Low-mass Pairs of
Kinematically Equivalent Stars (SLoWPoKES; Dhital et al. 2010, Cat.
J/AJ/139/2566; Dhital et al. 2015, Cat. J/AJ/150/57) sample: high- to
medium-mass wide-binary pairs. We use the proper motions, parallaxes,
and positions from the first Gaia data release, combined with the
photometry, astrometry, and proper motions from SDSS to identify
binary pairs between multiple Tycho-2 stars and between Tycho-2 and
SDSS point sources. We call this extension of the SLoWPoKES catalog
the Gaia Assorted Mass Binaries Long Excluded from SLoWPoKES
(GAMBLES).
Table1 provides the position and magnitude information for each
long-lived wide binary in the GAMBLES sample; Table2 provides the
proper motion, distance and Galactic model information for each
long-lived wide binary in the GAMBLES sample; and Table3 provides the
estimated physical quantities for each long-lived binary in the
GAMBLES sample. Quantities for GAMBLES binaries that are not in the
final sample can be found on the Filtergraph portal with the URL
https://filtergraph.com/gambles.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 180 543 Positions and magnitudes of Gaia Assorted Mass
Binaries Long Excluded from SloWPoKES (GAMBLES)
long-lived wide binaries
table2.dat 102 543 Astrometric information for Gaia Assorted Mass
Binaries Long Excluded from SloWPoKES (GAMBLES)
long-lived wide binaries
table3.dat 51 543 Calculated quantities for Gaia Assorted Mass
Binaries Long Excluded from SloWPoKES (GAMBLES)
long-lived wide binaries
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See also:
I/337 : Gaia DR1 (Gaia Collaboration, 2016)
V/147 : The SDSS Photometric Catalogue, Release 12 (Alam+, 2015)
I/259 : The Tycho-2 Catalogue (Hog+ 2000)
I/239 : The Hipparcos and Tycho Catalogues (ESA 1997)
J/AJ/153/257 : Comoving stars in Gaia DR1 (Oh+, 2017)
J/ApJ/831/L6 : Eclipsing binary parallaxes with Gaia data (Stassun+, 2016)
J/AJ/150/57 : SLoWPoKES-II catalog (Dhital+, 2015)
J/AJ/139/2566 : SLoWPoKES catalog (Dhital+, 2010)
https://filtergraph.com/gambles : GAMBLES catalog
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- --- [GBL]
4- 12 A9 --- GAMBLES GAMBLES identification (G1)
14- 25 A12 --- Tyc1 Tycho2 identifier for the primary
27- 32 I6 --- HIP1 [212/116068]? HIP identifier for the primary
34- 52 I19 --- objID ? SDSS identifier for the secondary
54- 65 A12 --- Tyc2 Tycho2 identifier for the secondary
67- 72 I6 --- HIP2 [8906/120404]? HIP identifier for the secondary
74- 75 I2 h RA1h Hour of Right Ascension primary (ICRS) at epoch
2015.0 (G2)
77- 78 I2 min RA1m Minute of Right Ascension primary (ICRS) at
epoch 2015.0 (G2)
80- 84 F5.2 s RA1s Second of Right Ascension primary (ICRS) at
epoch 2015.0 (G2)
86 A1 --- DE1- Sign of the Declination of the primary (G2)
87- 88 I2 deg DE1d Degree of Declination primary (ICRS) at epoch
2015.0 (G2)
90- 91 I2 arcmin DE1m Minute of Declination primary (ICRS) at epoch
2015.0 (G2)
93- 96 F4.1 arcsec DE1s Second of Declination primary (ICRS) at epoch
2015.0 (G2)
98- 99 I2 h RA2h Hour of Right Ascension secondary (ICRS) at
epoch 2015.0 (G2)
101-102 I2 min RA2m Minute of Right Ascension secondary (ICRS) at
epoch 2015.0 (G2)
104-108 F5.2 s RA2s Second of Right Ascension secondary (ICRS) at
epoch 2015.0 (G2)
110 A1 --- DE2- Sign of the Declination of the secondary (G2)
111-112 I2 deg DE2d Degree of Declination secondary (ICRS) at epoch
2015.0 (G2)
114-115 I2 arcmin DE2m Minute of Declination secondary (ICRS) at epoch
2015.0 (G2)
117-120 F4.1 arcsec DE2s Second of Declination secondary (ICRS) at epoch
2015.0 (G2)
122-126 F5.2 mag umag1 [6.25/15.5] SDSS u magnitude for the primary
128-132 F5.2 mag umag2 [7.74/26.06] SDSS u magnitude for the secondary
134-138 F5.2 mag gmag1 [5.22/12.89] SDSS g magnitude for the primary
140-144 F5.2 mag gmag2 [6.68/22.27] SDSS g magnitude for the secondary
146-150 F5.2 mag rmag1 [5.48/12.43] SDSS r magnitude for the primary
152-156 F5.2 mag rmag2 [6.61/20.86] SDSS r magnitude for the secondary
158-162 F5.2 mag imag1 [5.69/12.32] SDSS i magnitude for the primary
164-168 F5.2 mag imag2 [6.38/19.33] SDSS i magnitude for the secondary
170-174 F5.2 mag zmag1 [5.82/12.3] SDSS z magnitude for the primary
176-180 F5.2 mag zmag2 [6.27/18.51] SDSS z magnitude for the secondary
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 A3 --- --- [GBL]
4- 12 A9 --- GAMBLES GAMBLES identification (G1)
14- 20 F7.2 mas/yr pmRA1 [-139.3/95.46] Proper motion in Right
Ascension of the primary (G2)
22- 25 F4.2 mas/yr e_pmRA1 [0.02/5.31] Error in pmRA1 (G2)
27- 33 F7.2 mas/yr pmDE1 [-236.36/106.92] Proper motion in Declination
of the primary (G2)
35- 38 F4.2 mas/yr e_pmDE1 [0.02/3.03] Error in pmDE1 (G2)
40- 46 F7.2 mas/yr pmRA2 [-137.1/93.2] Proper motion in Right Ascension
of the secondary (G2)
48- 52 F5.2 mas/yr e_pmRA2 [0.03/56.5] Error in pmRA2 (G2)
54- 60 F7.2 mas/yr pmDE2 [-234.1/111.4] Proper motion in Declination of
the secondary (G2)
62- 66 F5.2 mas/yr e_pmDE2 [0.02/56.5] Error in pmDE2 (G2)
68- 71 F4.2 pc Seppc [0/3.3] Separation of the pair (in pc)
73- 80 F8.1 AU Sepau [811.9/674496] Separation of the pair (in AU)
82- 88 F7.2 arcsec Separc [3.5/3094.8] Separation of the pair
(in arcsecs)
90- 92 I3 pc Dist1 [53/780] Distance to the primary
94- 96 I3 pc Dist2 [52/781] Distance to the secondary
98-102 F5.3 --- V5 [0.001/0.05] The 5D Voxel statistic V5 (false
positive probability) (1)
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Note (1): Similar to previous Sloan Low-mass Pairs of Kinematically Equivalent
Stars (SLoWPoKES; Dhital et al. 2010, Cat. J/AJ/139/2566; Dhital et al.
2015, Cat. J/AJ/150/57) work, we employ a five-dimensional model to
recreate the stellar populations along a given line of sight and calculate
the probability of a chance alignment. We stress that this metric is not a
formal probability, but instead is an estimate of the number density of
stars with similar characteristics in a given 5D Voxel. Stars that returned
a value of V5=0 (i.e., <1 in 1000 stars) were assigned V5=0.001 because
their true V5 was below the resolution of our Monte-Carlo procedure. We
selected candidate pairs which return a value of V5≤0.05 as bona fide
wide-binary pairs following previous SLoWPoKES work (Dhital et al. 2010,
Cat. J/AJ/139/2566; Dhital et al. 2015, Cat. J/AJ/150/57). Please refer to
Section 3.2 in the paper for further details.
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 A3 --- --- [GBL]
4- 12 A9 --- GAMBLES GAMBLES identification (G1)
14- 15 A2 --- SpT1 Spectral type of the primary (SpT1)
17- 18 A2 --- SpT2 Spectral type of the secondary (SpT2)
20- 22 F3.1 Msun Mass1 [0.7/2.1] Mass of the primary (M1)
24- 26 F3.1 Msun Mass2 [0.2/2] Mass of the secondary (M2)
28- 32 F5.2 mag Hg1 [1.5/13.5] Reduced proper motion of the primary
in g (Hg1)
34- 38 F5.2 mag Hg2 [2.7/21.1] Reduced proper motion of the
secondary in g (Hg2)
40- 44 F5.2 [10-7W] logBE [40.5/43.4] Log of the binding energy
(in erg/s) (2)
46- 51 F6.2 Gyr DL [1.5/659.4] Dissipation lifetime (3)
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Note (2):
We calculated the binding energies of the Gaia Assorted Mass Binaries Long
Excluded from SLoWPoKES (GAMBLES) sample to quantify the physicality of
many of the widest pairs. We define the binding energy of a pair, measured
in erg, as the gravitational potential energy between the two objects:
U=(GM1M2)/a, where:
G = The gravitational constant;
M1 = Mass of the primary component;
M2 = Mass of the secondary component;
a = The distance between the two stars.
Please see Section 4.4.1 for additional details.
Note (3):
Even if a binary pair possesses the requisite binding energy to remain
stable, the large separation coupled with the local Galactic environment
could cause the pair to dissipate over time. Encounters with other stars,
molecular clouds, or even subtle changes in the overall Galactic potential
can combine to disrupt the system's stability and cause it to break apart
(Weinberg et al. 1987ApJ...312..367W 1987ApJ...312..367W). We calculated the average
dissipation lifetime of a given binary to aid in our interpretation of the
possible stability of each system. We followed the logic of Weinberg et al.
(1987ApJ...312..367W 1987ApJ...312..367W), Close et al. (2007ApJ...660.1492C 2007ApJ...660.1492C), and Dhital et
al. 2010 (Cat. J/AJ/139/2566) and used the below approximation, based on
the advection and diffusion of orbital binding energy due to small
encounters, to calculate the expected dissipation lifetimes:
a≃1.212(Mtot/t*), where:
a = The separation in pc;
Mtot = The total mass of the system in solar masses;
t* = The lifetime of the binary in Gyr.
Please see Section 4.4.2 for more details.
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Global Notes:
Note (G1): The Gaia Assorted Mass Binaries Long Excluded from SLoWPoKES
(GAMBLES) identifier is created using the mean position of the pair, rather
than the position of the primary, to avoid confusion between pairs where
the primary is linked to more than 1 secondary.
Note (G2): We use the proper motions, parallaxes, and positions from the first
Gaia data release (see Gaia Collaboration 2016, Cat. I/337), combined with
the photometry, astrometry, and proper motions from SDSS to identify
binary pairs between multiple Tycho-2 stars and between Tycho-2 and SDSS
point sources.
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History:
From electronic version of the journal
(End) Prepared by [AAS]; Sylvain Guehenneux [CDS] 22-Aug-2017