J/AJ/143/31 Properties of fragile binary candidates in SDSS DR8 (Zhao+, 2012)
Fragile binary candidates in the SDSS DR8 spectroscopic archive.
Zhao J.K., Oswalt T.D., Zhao G.
<Astron. J., 143, 31 (2012)>
=2012AJ....143...31Z 2012AJ....143...31Z
ADC_Keywords: Stars, double and multiple ; Proper motions ; Photometry, SDSS ;
Space velocities ; Stars, distances ; Radial velocities
Keywords: stars: activity - stars: chromospheres
Abstract:
We present a catalog of 80 very wide fragile binary candidates
(projected separations >10000AU) from the Sloan Digital Sky Survey
Data Release Eight spectral archive. The pairs were selected based on
proper motion, radial velocity, metallicity, and photometric parallax
criteria. The angular separations of these pairs range from 3" to
250". The peak in the metallicity distribution of these pairs is about
-0.5dex of solar metallicity. Space motions and reduced proper motion
diagrams indicate that all these pairs are members of the disk. The
chromospheric activity index SHK of each component in 38 binary
candidates having spectra of high signal-to-noise ratio and member
stars of three open clusters (NGC 2420, M67, and NGC 6791) were
measured. The SHK versus color relation for these binary candidates
is consistent with the trend seen in these open clusters. The ages
implied by this relation suggest that fragile wide pairs can survive
longer than 8Gyr.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 114 80 Properties of fragile binary candidates
(projected separations >104AU=0.0485pc)
table2.dat 78 80 Kinematical properties of fragile binary
candidates
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See also:
V/139 : The SDSS Photometric Catalog, Release 9 (Adelman-McCarthy+, 2012)
I/298 : LSPM-North Catalog (Lepine+, 2005)
I/121 : Common proper motions stars in AGK3 (Halbwachs, 1986)
J/AJ/139/2566 : SLoWPoKES catalog (Dhital+, 2010)
J/AJ/133/889 : Faint companions of Hipparcos stars (Lepine+, 2007)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Seq [1/80] Running sequence number
(<[ZOZ2012] NN> in Simbad)
4- 19 A16 --- SDSS1 SDSS primary ID (JHHMMSSS.s+DDMMSS)
21- 36 A16 --- SDSS2 SDSS secondary ID (JHHMMSSS.s+DDMMSS)
38- 40 I3 mas/yr pmRA1 Proper motion in Right Ascension for primary
42- 43 I2 mas/yr pmRA2 Proper motion in Right Ascension for secondary
45- 47 I3 mas/yr pmDE1 Proper motion in Declination for primary
49- 51 I3 mas/yr pmDE2 Proper motion in Declination for secondary
53- 56 I4 km/s RV1 [-102/82] Radial velocity of primary (1)
58- 61 I4 km/s RV2 [-115/87] Radial velocity of secondary (1)
63- 67 F5.2 [Sun] [Fe/H]1 Metallicity of primary
69- 73 F5.2 [Sun] [Fe/H]2 Metallicity of secondary
75- 79 F5.2 mag rmag1 [12.89/18.47] SDSS r magnitude of primary
81- 85 F5.2 mag rmag2 [13.4/18.81] SDSS r magnitude of secondary
87- 90 F4.2 mag (g-i)1 The SDSS (g-i) color index of primary
92- 95 F4.2 mag (g-i)2 The SDSS (g-i) color index of secondary
97- 98 A2 --- SpT1 MK spectral type of primary
100-101 A2 --- SpT2 MK spectral type of secondary
103-108 F6.2 arcsec Asep [8.41/188.62] Angular separation
110-114 F5.3 pc Psep [0.072/0.478] Projected separation
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Note (1): From ELODIE stellar library (Moultaka et al., 2004PASP..116..693M 2004PASP..116..693M).
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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- 2 I2 --- Seq [1/80] Running sequence number
4- 7 I4 km/s U1 U component of Galactic velocity for primary (2)
9- 10 I2 km/s e_U1 Uncertainty on U1
12- 14 I3 km/s V1 V component of Galactic velocity for primary (3)
16- 17 I2 km/s e_V1 Uncertainty on V1
19- 21 I3 km/s W1 W component of Galactic velocity for primary (4)
23- 24 I2 km/s e_W1 Uncertainty on W1
26- 29 I4 km/s U2 U component of Galactic velocity for secondary (2)
31- 32 I2 km/s e_U2 Uncertainty on U2
34- 37 I4 km/s V2 V component of Galactic velocity for secondary (3)
39- 40 I2 km/s e_V2 Uncertainty on V2
42- 44 I3 km/s W2 W component of Galactic velocity for secondary (4)
46- 47 I2 km/s e_W2 Uncertainty on W2
49- 52 I4 pc r1 [294/4319] Distance for primary
54- 57 I4 pc r2 [312/3973] Distance for secondary
59- 60 I2 km/s DU [0/70] U difference between the two components
62- 63 I2 km/s DV [0/56] V difference between the two components
65- 66 I2 km/s DW [0/95] W difference between the two components
68- 71 I4 pc Dr [10/1181] Difference in distances
73- 76 A4 --- Age Age consistency for the 38 binaries with S/N>40
(Y, N or NULL) (5)
78 A1 --- CL [A-E] Confidence level for being a physical
pair (A=candidate is very likely a physical
pair to E=lowest probability)
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Note (2): Positive in the direction radially outward from the Galactic center
Note (3): Positive in the direction of Galactic rotation
Note (4): Positive perpendicular to the plane of the Galaxy in the direction
of the north Galactic pole.
Note (5): Age consistency flag (details in section 4.3):
Y = consistent ages (for two components)
N = inconsistent ages
NULL = stars not in the sample of the 38 fragile binaries candidates
with S/N>40.
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History:
From electronic version of the journal
(End) Sylvain Guehenneux [CDS] 09-Apr-2013