J/MNRAS/466/2983 Wide low very low-mass binary systems (Galvez-Ortiz+, 2017)
Discovery of wide low and very low-mass binary systems using
Virtual Observatory tools.
Galvez-Ortiz M.C., Solano E., Lodieu N., Aberasturi M.
<Mon. Not. R. Astron. Soc., 466, 2983-3006 (2017)>
=2017MNRAS.466.2983G 2017MNRAS.466.2983G (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple
Keywords: astronomical data bases: miscellaneous - virtual observatory tools -
binaries: general - brown dwarfs
Abstract:
The frequency of multiple systems and their properties are key
constraints of stellar formation and evolution. Formation mechanisms
of very low-mass (VLM) objects are still under considerable debate,
and an accurate assessment of their multiplicity and orbital
properties is essential for constraining current theoretical models.
Taking advantage of the virtual observatory capabilities, we looked
for comoving low and VLM binary (or multiple) systems using the Large
Area Survey of the UKIDSS LAS DR10, SDSS DR9 and the 2MASS Catalogues.
Other catalogues (WISE, GLIMPSE, SuperCosmos, etc.) were used to
derive the physical parameters of the systems. We report the
identification of 36 low and VLM (∼M0-L0 spectral types)
candidates to binary/multiple system (separations between 200 and
92000au), whose physical association is confirmed through common
proper motion, distance and low probability of chance alignment. This
new system list notably increases the previous sampling in their
mass-separation parameter space (∼100). We have also found 50
low-mass objects that we can classify as ∼L0-T2 according to
their photometric information. Only one of these objects presents a
common proper motion high-mass companion. Although we could not
constrain the age of the majority of the candidates, probably most of
them are still bound except four that may be under disruption
processes. We suggest that our sample could be divided in two
populations: one tightly bound wide VLM systems that are expected to
last more than 10 Gyr, and other formed by weak bound wide VLM systems
that will dissipate within a few Gyr.
Description:
Taking advantage of VO tools, we could identify 36 new low and VLM
systems (M0.5-L0 spectral types) with separations in the ∼200-92000au
range. We also provided distances and masses of 11 pairs previously
marked as binaries in the literature, giving spectral classification
for seven of them for the first time and improving the classification
for one of them using photometry and spectroscopy.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 105 84 Candidate position data for group A
(2MASS, SDSS and UKIDSS)
table2.dat 109 18 Candidate position data for group B
(2MASS, SDSS and WISE)
table3.dat 83 84 *Physical properties of newly identified
low-mass component systems: group A
table4.dat 84 18 *Physical properties of newly identified
low-mass component systems: group B
table5.dat 126 6 Physical properties of the identified higher
mass tertiaries to the M-M systems
table6.dat 85 2 Physical properties of the new L-F system
tablea1.dat 103 50 L-T candidates
tablea2.dat 91 73 *Wide low mass binaries from the literature: 2MASS
tablea3.dat 28 25 Wide low-mass binaries from the literature:
SLoWPoKES I
refs.dat 143 24 References
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Note on table3.dat, table4.dat: Components ordered by spectral type, assignating
primary position to the earliest type of the components.
Note on tablea2.dat: Separations over 200au and total system masses under
1M☉.
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See also:
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
II/319 : UKIDSS-DR9 LAS, GCS and DXS Surveys (Lawrence+ 2012)
V/139 : The SDSS Photometric Catalog, Release 9 (Adelman-McCarthy+, 2012)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 16 A16 --- 2MASS 2MASS ID (HHMMSSss+DDMMSSs)
17 A1 --- n_2MASS [ab] Note on 2MASS (1)
19- 28 F10.6 deg RAdeg 2MASS right ascension (J2000)
30- 38 F9.6 deg DEdeg 2MASS declination (J2000)
40- 49 F10.6 deg RAsdeg SDSS right ascension (J2000)
51- 59 F9.6 deg DEsdeg SDSS declination (J2000)
61- 70 F10.6 deg RAudeg UKIDSS right ascension (J2000)
72- 80 F9.6 deg DEudeg UKIDSS declination (J2000)
82- 85 I4 mas/yr pmRA Proper motion along RA, pmRA*cosDE
87- 90 F4.1 mas/yr e_pmRA rms uncertainty on pmRA
92- 95 I4 mas/yr pmDE Proper motion along DE
97-101 F5.2 mas/yr e_pmDE rms uncertainty on pmDE
102-105 I4 mas/yr pm Total proper motion
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Note (1): Notes as follows:
a = previously found in WDS catalogue
b = previously found in SLoWPoKES II
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 16 A16 --- 2MASS 2MASS ID (HHMMSSss+DDMMSSs)
17 A1 --- n_2MASS [a] Note on 2MASS (1)
19- 28 F10.6 deg RAdeg 2MASS right ascension (J2000)
30- 39 F10.6 deg DEdeg 2MASS declination (J2000)
41- 50 F10.6 deg RAsdeg SDSS right ascension (J2000)
51 A1 --- n_RAsdeg [c] Note on RAsdeg (1)
53- 62 F10.6 deg DEsdeg SDSS declination (J2000)
63 A1 --- n_DEsdeg [c] Note on RAsdeg (1)
66- 75 F10.6 deg RAwdeg ? WISE right ascension (J2000)
76 A1 --- n_RAwdeg [bd] Note on n_RAwdeg (1)
79- 88 F10.6 deg DEwdeg ? WISE declination (J2000)
89 A1 --- n_DEwdeg [bd] Note on n_RAwdeg (1)
91- 94 I4 mas/yr pmRA Proper motion along RA, pmRA*cosDE
96- 97 I2 mas/yr e_pmRA rms uncertainty on pmRA
99-102 I4 mas/yr pmDE Proper motion along DE
104-105 I2 mas/yr e_pmDE rms uncertainty on pmDE
107-109 I3 mas/yr pm Total proper motion
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Note (1): Notes as follows:
a = previously found in WDS catalogue
b = Not seen in WISE
c = GLIPMSE data base coordinates
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Byte-by-byte Description of file: table3.dat table4.dat
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Bytes Format Units Label Explanations
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1- 16 A16 --- 2MASS 2MASS id (HHMMSSss+DDMMSSs)
18- 21 A4 --- SpType Spectral type from photometry (Section 4.2.4)
22 A1 --- n_SpType [f] Note on SpType (1)
23- 28 A6 --- SpType2 Spectral type from spectroscopy (Section 4.2.3)
31- 34 I4 K Teff Effective temperature from VOSA (Section 4.2.3)
35 A1 --- n_Teff [a] Note on Teff (1)
37- 39 F3.1 [cm/s2] logg ? Surface gravity from VOSA (Section 4.2.3)
41- 44 F4.2 Msun Mass1 ? Mass from VOSA (Section 4.2.3)
46- 49 F4.2 Msun Mass2 Mass from From Kraus & Hillenbrand (2007) (2)
50 A1 --- n_Mass2 [dg] Note on Mass (1)
52- 57 F6.2 pc Dist Distance
58 A1 --- n_Dist [beh] Note on Dist (1)
59- 60 I2 pc e_Dist ? Error on Dist (lower value) (only in table 3)
62- 63 I2 pc E_Dist ? Error on Dist (upper value) (only in table 3)
65- 70 F6.2 arcsec rho ? Angular separation
72- 76 I5 AU Sep ? Separation
78- 84 F7.2 10+33J U ? Binding (gravitational potential) energy (3)
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Note (1): Note as follows:
f = From (H-Ks) colour (Section 4.2.4).
a = No good fit of the SED was found, 3500-3600K was the best but we take his
value with caution, relying more in the temperature obtained by other
methods.
d = From Mi and Mr since z value is not reliable.
g = From MJ relations in Kraus & Hillenbrand (2007AJ....134.2340K 2007AJ....134.2340K,
Cat. J/AJ/134/2340). See Section 4.2.3.
b = From Mr-(i-z) relation in Bochanski et al. (2010AJ....139.2679B 2010AJ....139.2679B; Table 4),
since the (r-z) colour is outside the allowed range for the Mr-(r-z)
calibration. See Section 4.2.1.
e = From Mr-(r-i) relation in Bochanski et al. (2010AJ....139.2679B 2010AJ....139.2679B; Table 4),
since z value is not reliable. See Section 4.2.1.
h = From MJ-spectral type relation in Hawley et al. (2002AJ....123.3409H 2002AJ....123.3409H,
J/AJ/123/3409) (Section 4.2.4).
Note (2): From Kraus & Hillenbrand (2007AJ....134.2340K 2007AJ....134.2340K, Cat. J/AJ/134/2340)
Table 5 colour-mass relations (Section 4.2.3).
Note (3): Low mass and VLM wide binary systems are expected to have very low
(absolute values of) gravitational potential (binding) energies, Ug=-GM1M2/r
(with M1 and M2 the masses of each component and r the distance between them).
We have calculated the binding energies for our systems using the value of
masses obtained by VOSA, and the projected physical separation (instead of the
true separation), and compare them with those of other low and VLM wide
separation binaries from the literature. We consider a physically bound system
when binding energy is over 1033J (Dhital et al. 2010AJ....139.2566D 2010AJ....139.2566D,
J/AJ/139/2566). Nine of the system show energies under this limit though.
We discuss if these candidates are bound or not in Section 7.
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 16 A16 --- ID1 System Id, 2MASS (first source)
18- 33 A16 --- ID2 System Id, 2MASS (second source)
35- 53 I19 --- PPMXL PPMXL Id
55- 64 F10.6 deg RAdeg Right ascension (J2000)
66- 74 F9.6 deg DEdeg Declination (J2000)
76- 78 I3 mas/yr pmRA Proper motion along RA, pmRA*cosDE
80- 82 F3.1 mas/yr e_pmRA rms uncertainty on pmRA
84- 87 I4 mas/yr pmDE Proper motion along DE
89- 91 F3.1 mas/yr e_pmDE rms uncertainty on pmDE
93- 94 A2 --- SpType Spectral type
96- 99 I4 K Teff Effective temperature
101-104 F4.2 Msun Mass Mass
106-111 F6.2 pc Dist Distance
113-121 F9.2 AU Sep Separation
123-126 F4.1 10+33J U Binding (gravitational potential) energy
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Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
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1- 26 A26 --- Name 2MASS object Id
27- 30 I4 mas/yr pmRA Proper motion along RA, pmRA*cosDE
32- 34 F3.1 mas/yr e_pmRA rms uncertainty on pmRA
36- 39 I4 mas/yr pmDE Proper motion along DE
41- 43 F3.1 mas/yr e_pmDE rms uncertainty on pmDE
45- 47 I3 mas/yr pm Total proper motion
49- 52 A4 --- SpType Spectral type
53 A1 --- n_SpType [ac] Note on SpType (1)
55- 60 F6.1 K Teff Effective temperature from VOSA (Section 4.2.3)
62- 64 F3.1 [cm/s1] logg ? Surface gravity
66- 70 F5.3 Msun Mass Mass
71 A1 --- n_Mass [bc] Note on Mass (1)
73- 74 I2 pc Dist Distance
76- 81 I6 AU Sep ? Separation
83- 85 F3.1 10+33J U ? Binding (gravitational potential) energy
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Note (1): Notes as follows:
a = From photometry (Section 4.2.4).
b = Value state by default for an L dwarf. See Section 6.
c = From temperature and spectral types in Gray (1992, The Observation and
Analysis of Stellar Photospheres. Cambridge Univ. Press., Cambridge).
See Section 6.
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Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 16 A16 --- 2MASS 2MASS ID (HHMMSSss+DDMMSSs)
17- 18 A2 --- n_2MASS [* a] Note on 2MASS (1)
20- 29 F10.6 deg RAdeg 2MASS right ascension (J2000)
31- 39 F9.6 deg DEdeg 2MASS declination (J2000)
41- 50 F10.6 deg RAsdeg SDSS right ascension (J2000)
52- 60 F9.6 deg DEsdeg SDSS declination (J2000)
62- 66 F5.2 mag Jmag 2MASS J magnitude
68- 71 I4 mas/yr pmRA ? Proper motion along RA, pmRA*cosDE
73- 76 I4 mas/yr pmDE ? Proper motion along DE
78- 80 I3 mas/yr pm ? Total proper motion
82- 86 A5 --- SpType Spectral type from photometry (Section 4.2.4)
87 A1 --- n_SpType [abc] note on SpType (1)
90- 95 F6.1 K Teff Effevctive temperature from VOSA
(Section 4.2.3)
97- 99 F3.1 [cm/s2] logg Surface gravity from VOSA (Section 4.2.3).
101-102 I2 pc Dist ? Distance
103 A1 --- n_Dist [ac] Note on Dist (1)
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Note (1): Notes as follows:
* = These objects may correspond to low metallicity Ls, or L subdwarfs,
due to their proper motion and colours characteristics, see Section 5
** = Spectrum of the target is available and discussed in Section 5
a = from (i-J) colour-spectral type relation of Schmidt et al.
(2010AJ....139.1808S 2010AJ....139.1808S, Cat. J/AJ/139/1808) only since (i-z) criterion is
not fulfilled
b = Classified as L dwarf by SDSS pipeline
c = Since (i-z) and (i-J) criteria of Schmidt et al. (2010AJ....139.1808S 2010AJ....139.1808S,
Cat. J/AJ/139/1808) are not fulfilled, the spectral type is calculated
from the rest of the colours in Table 3 of Schmidt et al.
(2010AJ....139.1808S 2010AJ....139.1808S, Cat. J/AJ/139/1808)
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Byte-by-byte Description of file: tablea2.dat
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Bytes Format Units Label Explanations
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1- 50 A50 --- System System name, as appeared in reference paper
51 A1 --- n_System [a] Note on System (1)
53- 57 I5 AU Sep Separation
59- 63 F5.3 Msun MassP Mass of the primary
65- 69 F5.3 Msun MassS ? Mass of the secondary
71- 74 A4 --- n_MassS Spectral type for star without secondary mass (2)
77- 82 F6.1 10+33J U ? Binding (gravitational potential) energy
84- 91 A8 --- Ref Reference code, in refs.dat file
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Note (1): a: component is a binary M8+L0. Its total mass is larger than
primary M6.4 mass.
Note (2): For spectral types later than L0 without mass determination in the
literature, no mass has been assigned, an we list the spectral type.
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Byte-by-byte Description of file: tablea3.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- Name Name (SLWHHMM+DD, SLW JHHMM+DD in Simbad)
12- 16 I5 AU Sep Separation
18- 21 F4.2 Msun MassT Total mass (1)
23- 28 F6.1 10+33J U Binding energy (1)
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Note (1): Binding energies are calculated using estimated masses as a function
of spectral type (Kraus & Hillenbrand, 2007AJ....134.2340K 2007AJ....134.2340K,
Cat. J/AJ/134/2340). When spectral type not available, it was assumed to be
an equal-mass binary, Dhital et al. (2010AJ....139.2566D 2010AJ....139.2566D,).
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Byte-by-byte Description of file: refs.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Ref Reference code
4- 22 A19 --- BibCode BibCode
24- 40 A17 --- Aut Author's name
42-191 A150 --- Com Comments
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 21-Oct-2019