J/MNRAS/480/4884 Gaia wide binaries (El-Badry+, 2018)
Imprints of white dwarf recoil in the separation distribution of
Gaia wide binaries.
El-Badry K., Rix H.-W.
<Mon. Not. R. Astron. Soc., 480, 4884-4902 (2018)>
=2018MNRAS.480.4884E 2018MNRAS.480.4884E (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Optical
Keywords: binaries: visual - stars: mass-loss - white dwarfs -
Galaxy: stellar content
Abstract:
We construct from Gaia DR2 an extensive and very pure (≲0.2 per cent
contamination) catalogue of wide binaries containing main-sequence
(MS) and white dwarf (WD) components within 200 pc of the Sun. The
public catalogue contains, after removal of clusters and resolved
higher order multiples, >50000MS/MS, >3000WD/MS, and nearly 400WD/WD
binaries with projected separations of 50≲s/au<50000. Accounting for
incompleteness and selection effects, we model the separation
distribution of each class of binaries as a broken power law,
revealing marked differences between the three populations. The
separation distribution of MS/MS systems is nearly consistent with a
single power law of slope -1.6 over at least 500<s/au<50000, with
marginal steepening at s>10000au. In contrast, the separation
distributions of WD/MS and WD/WD binaries show distinct breaks at
∼3000 and ∼1500au, respectively: they are flatter than the MS/MS
distribution at small separations and steeper at large separations.
Using binary population synthesis models, we show that these breaks
are unlikely to be caused by external factors but can be explained if
the WDs incur a kick of ∼0.75km/s during their formation, presumably
due to asymmetric mass-loss. The data rule out typical kick velocities
above 2km/s. Our results imply that most wide binaries with
separations exceeding a few thousand au become unbound during post-MS
evolution.
Description:
We have constructed a catalogue of high-confidence wide binaries using
astrometric data from Gaia DR2. We determined with high fidelity the
physical separation distributions of MS/MS, WD/MS, and WD/WD binaries
over the separation range 1.5≲log(a/au)≲4.7.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablee1.dat 742 55128 Catalogue of wide binaries within 200 pc
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See also:
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
Byte-by-byte Description of file: tablee1.dat
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Bytes Format Units Label Explanations
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1- 19 I19 --- ID2 Star 2 Gaia DR2 source id (source_id2)
21- 42 F22.18 deg RA2deg Star 2 right ascension (ICRS) at Ep=2015.5
(ra2)
44- 66 F23.19 deg DE2deg Star 2 declination (ICRS) at Ep=2015.5
(dec2)
68- 80 F13.6 --- chi2AL2 Star 2 astrometric goodness-of-fit in the
along-scan direction
(astrometricchi2al_2)
82- 85 I4 --- NgAL2 Star 2 astrometric goodness-of-fit in the
along-scan direction
(astrometricngoodobsal2)
87- 97 F11.6 --- RFG2 Star 2 G-band mean flux divided by its error
(photgmeanfluxover_error2)
99-111 F13.7 --- RFRP2 Star 2 RP-band mean flux divided by its
error (photrpmeanfluxover_error2)
113-125 F13.7 --- RFBP2 Star 2 BP-band mean flux divided by its
error (photbpmeanfluxover_error2)
127-135 F9.7 --- E(BR/RP)2 Star 2 BP/RP excess factor
(photbprpexcessfactor2)
137-161 F25.19 mas/yr pmRA2 Star 2 proper motion along RA (pmra2)
163-182 F20.18 mas/yr e_pmRA2 Star 2 proper motion along RA error
(pmra_error2)
184-208 F25.19 mas/yr pmDE2 Star 2 proper motion along DE(pmdec2)
210-229 F20.18 mas/yr e_pmDE2 Star 2 proper motion along DE error
(pmdec_error2)
231-240 F10.7 mag Gmag2 Star 2 G magnitude (photgmean_mag2)
242-251 F10.7 mag BPmag2 Star 2 BP magnitude (photbpmean_mag2)
253-262 F10.7 mag RPmag2 Star 2 RP magnitude (photrpmean_mag2)
264-283 F20.16 mas plx2 Star 2 parallax (parallax2)
285-296 F12.7 mas e_plx2 Star 2 parallax error (parallaxovererror2)
298-322 F25.20 km/s RV2 ? Star 2 radial velocity (radial_velocity2
324-343 F20.17 km/s e_RV2 ? Star 2 radial velocity
(radialvelocityerror2)
345-346 I2 --- o_RV2 Star 2 number of transits used to compute
radial velocity (rvnbtransits2)
348-366 I19 --- ID1 Star 1 Gaia DR3 source id (source_id)
368-389 F22.18 deg RAdeg Star 1 right ascension (ICRS) at Ep=2015.5)
(ra)
391-413 F23.19 deg DEdeg Star 1 declination (ICRS) at Ep=2015.5 (dec)
415-439 F25.19 mas/yr pmRA Star 1 proper motion along RA (pmra)
441-460 F20.18 mas/yr e_pmRA Star 1 proper motion along RA error
(pmra_error)
462-486 F25.19 mas/yr pmDE Star 1 proper motion along DE (pmdec)
488-507 F20.18 mas/yr e_pmDE Star 1 proper motion along DE error
(pmdec_error)
509-518 F10.7 mag Gmag Star 1 G magnitude (photgmean_mag)
520-529 F10.7 mag BPmag Star 1 BP magnitude (photbpmean_mag)
531-540 F10.7 mag RPmag Star 1 RP magnitude (photrpmean_mag)
542-561 F20.16 mas plx Star 1 parallax (parallax)
563-573 F11.6 mas e_plx Star 1 parallax error (parallaxovererror)
575-587 F13.6 --- chi2AL Star 1 astrometric goodness-of-fit in the
along-scan direction (astrometricchi2al)
589-592 I4 --- NgAL Star 1 astrometric goodness-of-fit in the
along-scan direction
(astrometricngoodobsal)
594-605 F12.6 --- RFG Star 1 G-band mean flux divided by its error
(photgmeanfluxover_error)
607-618 F12.6 --- RFRP Star 1 RP-band mean flux divided by its
error (photrpmeanfluxover_error)
620-632 F13.6 --- RFBP Star 1 BP-band mean flux divided by its
error (photbpmeanfluxover_error)
634-642 F9.7 --- E(BR/RP) Star 1 BP/RP excess factor
(photbprpexcessfactor)
644-667 F24.19 km/s RV ? Star 1 radial velocity (radial_velocity
669-688 F20.17 km/s e_RV ? Star 1 radial velocity error
(radialvelocityerror)
690-692 I3 --- o_RV Star 1 number of transits used to compute
radial velocity (rvnbtransits)
694-715 F22.20 deg Dist Angular separation between star 1 and star 2
(pairdistance)
717-720 A4 --- Class Type of binary; MSMS, WDMS, or WDWD
(binary_class)
722-742 F21.15 AU sAU Projected physical separation between two
stars (s_AU)
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 23-Sep-2023