J/MNRAS/488/2892 Gaia DR2 extremely low-mass WD candidates (Pelisoli+, 2019)
Gaia Data Release 2 catalogue of extremely low-mass white dwarf candidates.
Pelisoli I., Vos J.
<Mon. Not. R. Astron. Soc., 488, 2892-2903 (2019)>
=2019MNRAS.488.2892P 2019MNRAS.488.2892P (SIMBAD/NED BibCode)
ADC_Keywords: Stars, white dwarf ; Stars, double and multiple ;
Positional data ; Effective temperatures ; Stars, masses ;
Magnitudes ; Parallaxes, trigonometric ; Proper motions ;
Optical ; Infrared
Keywords: catalogues - surveys - binaries: close - white dwarfs
Abstract:
Extremely low-mass white dwarf stars (ELMs) are M<0.3M☉
helium-core white dwarfs born either as a result of a common-envelope
phase or after a stable Roche lobe overflow episode in a multiple
system. The Universe is not old enough for ELMs to have formed through
single-star evolution channels. As remnants of binary evolution, ELMs
can shed light onto the poorly understood phase of common-envelope
evolution and provide constraints to the physics of mass accretion.
Most known ELMs will merge in less than a Hubble time, providing an
important contribution to the signal to be detected by upcoming
space-based gravitational wave detectors. There are currently less
than 150 known ELMs; most were selected by colour, focusing on hot
objects, in a magnitude-limited survey of the Northern hemisphere
only. Recent theoretical models have predicted a much larger space
density for ELMs than estimated observationally based on this limited
sample. In order to perform meaningful comparisons with theoretical
models and test their predictions, a larger well-defined sample is
required. In this work, we present a catalogue of ELM candidates
selected from the second data release of Gaia (DR2). We have used
predictions from theoretical models and analysed the properties of the
known sample to map the space spanned by ELMs in the Gaia
Hertzsprung-Russell diagram. Defining a set of colour cuts and quality
flags, we have obtained a final sample of 5762 ELM candidates down to
Teff∼5000K.
Description:
We have compiled a catalogue of known ELMs from multiple sources in
the literature (see Table 1), and studied their Gaia parameters to map
the space spanned by ELMs in the observational HR diagram. We selected
objects given a colour criterion defined based on the known ELMs
(M<0.3M☉) with parallax uncertainty smaller than 20 per cent and
on evolutionary models, as well as quality control parameters based on
Lindegren et al. (2018A&A...616A...2L 2018A&A...616A...2L, Cat. I/345). Following our
selection, we have cross-matched the initial candidate sample with
SDSS in order to study those with available spectra. This step
revealed a large contamination by main-sequence stars and quasars,
which we were able to considerably reduce by applying a stricter cut
on parallaxovererror. To further reduce contamination by faint red
main-sequence stars, we have also studied the Gx(G-GRP) diagram, and
defined a further selection to exclude objects apparently scattered
from the main sequence. Finally, to limit the number of CVs and WD+MS
in the sample, we have studied multiple colour-colour diagrams to
separate objects with red excess, as well as X-ray emission. These
objects are also of interest as candidate CVs and WD+MS, and are
listed in Table C1. After applying all of these selection criteria,
our resulting catalogue of ELM candidates has 5672 objects, listed in
Table 2.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 311 119 Compiled catalogue of known ELMs
table2.dat 710 5762 Catalogue of ELM candidates from Gaia DR2
tablea1.dat 121 16 ELM stars as companions to millisecond pulsars
tablec1.dat 710 3526 Objects that were separated from our ELM
candidate selection due to X-ray detection or
red excess
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See also:
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
J/ApJ/818/155 : The ELM survey. VII. 15 new ELM white dwarf cand.
(Brown+, 2016)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 16 A16 --- ID Object identifier
18- 19 I2 h RAh Right ascension (J2000)
21- 22 I2 min RAm Right ascension (J2000)
24- 28 F5.2 s RAs Right ascension (J2000)
30 A1 --- DE- Declination (J2000)
31- 32 I2 deg DEd Declination (J2000)
34- 35 I2 arcmin DEm Declination (J2000)
37- 40 F4.1 arcsec DEs Declination (J2000)
42- 46 I5 K Teff ? Effective temperature
48- 51 I4 K e_Teff ? Error on Teff
53- 56 F4.2 [cm/s2] logg ? Surface gravity
58- 61 F4.2 [cm/s2] e_logg ? Error on logg
63- 67 F5.3 Msun M1 ? Estimated ELM white-dwarf mass
69- 73 F5.3 Msun E_M1 ? Error on M1
75- 82 F8.4 d Porb ? Orbital period
84- 89 F6.4 d e_Porb ? Error on Porb
91- 95 F5.1 km/s K ? Radial velocity semi-amplitude
97-100 F4.1 km/s e_K ? Error on K
102-105 F4.2 Msun M2min ? Minimum mass of the companion
107-114 F8.2 Gyr taumax ? Maximum gravitational wave merger time
116-136 A21 --- Ref Reference
138-156 A19 --- Bibcode Bibcode of the reference
158-176 I19 --- GaiaDR2 Gaia DR2 source identifier
178-185 F8.5 mas plx ? Parallax
187-193 F7.5 mas e_plx ? Error on plx
195-203 F9.5 mas/yr pmRA ? Proper motion on right ascension
205-211 F7.5 mas/yr e_pmRA ? Error on pmRA
213-222 F10.5 mas/yr pmDE ? Proper motion on declination
224-230 F7.5 mas/yr e_pmDE ? Error on pmDE
232-237 F6.3 mag Gmag Gaia DR2 G magnitude
239-243 F5.3 mag e_Gmag Error on Gmag
245-250 F6.3 mag BPmag Gaia DR2 BP magnitude
252-256 F5.3 mag e_BPmag Error on BPmag
258-263 F6.3 mag RPmag Gaia DR2 RP magnitude
265-269 F5.3 mag e_RPmag Error on RPmag
271-278 F8.5 mag BP-RP Gaia DR2 BP-RP colour
280-284 F5.3 mas epsi Gaia DR2 excess noise of the source
286-291 F6.2 --- Rplx ? Gaia DR2 parallax to parallax error ratio
293-297 F5.3 --- E(BP/RP) Gaia DR2 BP/RP excess factor
299-307 F9.3 --- chi2AL Gaia DR2 chi-square value
309-311 I3 --- NgAL Number of good observations from Gaia DR2
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Byte-by-byte Description of file: table2.dat tablec1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 I19 --- GaiaDR2 GaiaDR2 source identifier
21- 42 F22.18 deg RAdeg Right ascension (J2000)
44- 65 F22.18 deg DEdeg Declination (J2000)
67- 86 F20.17 mas plx Parallax
88-107 F20.18 mas e_plx Error on plx
109-132 F24.19 mas/yr pmRA Proper motion in right ascension
134-153 F20.18 mas/yr e_pmRA Error on pmRA
155-177 F23.18 mas/yr pmDE Proper motion in declination
179-198 F20.18 mas/yr e_pmDE Error on pmDE
200-209 F10.7 mag Gmag Gaia DR2 G magnitude
211-232 F22.20 mag e_Gmag Error on Gmag
234-243 F10.7 mag BPmag Gaia DR2 BP magnitude
245-265 F21.19 mag e_BPmag Error on BPmag
267-276 F10.7 mag RPmag Gaia DR2 RP magnitude
278-298 F21.19 mag e_RPmag Error on RPmag
300-313 F14.11 mag BP-RP Gaia DR2 BP-RP coulour
315-323 F9.7 --- E(BP/RP) Gaia DR2 BP/RP excess factor
325-336 F12.7 --- Rplx Gaia DR2 parallax to parallax error ratio
338-357 F20.18 --- epsi Gaia DR2 excess noise of the source
359-369 F11.6 --- chi2AL Gaia DR2 chi-square value
371-373 I3 --- NgAL Number of good observations from Gaia DR2
375-380 F6.3 mag W1mag ? WISE W1 (3.4um) band magnitude
382-386 F5.3 mag e_W1mag ? Error on W1mag
388-393 F6.3 mag W2mag ? WISE W2 (4.6um) band magnitude
395-399 F5.3 mag e_W2mag ? Error on W2mag
401-406 F6.3 mag W3mag ? WISE W3 (12um) band magnitude
408-412 F5.3 mag e_W3mag ? Error on W3mag
414-419 F6.3 mag W4mag ? WISE W4 (22um) band magnitude
421-425 F5.3 mag e_W4mag ? Error on W4mag
427-432 F6.3 mag Jmag ? 2MASS J-band magnitude
434-438 F5.3 mag e_Jmag ? Error on Jmag
440-445 F6.3 mag Hmag ? 2MASS H-band magnitude
447-451 F5.3 mag e_Hmag ? Error on Hmag
453-458 F6.3 mag Kmag ? 2MASS K-band magnitude
460-464 F5.3 mag e_Kmag ? Error on Kmag
466-471 F6.3 mag usdssmag ? SDSS u-band magnitude
473-478 F6.4 mag e_usdssmag ? Error on usdssmag
480-485 F6.3 mag gsdssmag ? SDSS g-band magnitude
487-492 F6.4 mag e_gsdssmag ? Error on gsdssmag
494-499 F6.3 mag rsdssmag ? SDSS r-band magnitude
501-506 F6.4 mag e_rsdssmag ? Error on rsdssmag
508-513 F6.3 mag isdssmag ? SDSS i-band magnitude
515-520 F6.4 mag e_isdssmag ? Error on isdssmag
522-527 F6.3 mag zsdssmag ? SDSS z-band magnitude
529-534 F6.4 mag e_zsdssmag ? Error on zsdssmag
536-542 F7.4 mag gPSmag ? PanSTARRS g-band magnitude
544-549 F6.4 mag e_gPSmag ? Error on gPSmag
551-557 F7.4 mag rPSmag ? PanSTARRS r-band magnitude
559-564 F6.4 mag e_rPSmag ? Error on rPSmag
566-572 F7.4 mag iPSmag ? PanSTARRS i-band magnitude
574-579 F6.4 mag e_iPSmag ? Error on iPSmag
581-587 F7.4 mag zPSmag ? PanSTARRS z-band magnitude
589-594 F6.4 mag e_zPSmag ? Error on zPSmag
596-602 F7.4 mag yPSmag ? PanSTARRS y-band magnitude
604-609 F6.4 mag e_yPSmag ? Error on yPSmag
611-616 F6.3 mag uSMmag ? SkyMapper u-band magnitude
618-623 F6.4 mag e_uSMmag ? Error on uSMmag
625-630 F6.3 mag vSMmag ? SkyMapper v-band magnitude
632-637 F6.4 mag e_vSMmag ? Error on vSMmag
639-644 F6.3 mag gSMmag ? SkyMapper g-band magnitude
646-651 F6.4 mag e_gSMmag ? Error on gSMmag
653-658 F6.3 mag rSMmag ? SkyMapper r-band magnitude
660-665 F6.4 mag e_rSMmag ? Error on rSMmag
667-672 F6.3 mag iSMmag ? SkyMapper i-band magnitude
674-679 F6.4 mag e_iSMmag ? Error on iSMmag
681-686 F6.3 mag zSMmag ? SkyMapper z-band magnitude
688-693 F6.4 mag e_zSMmag ? Error on zSMmag
695-701 F7.4 --- E(B-V)SandF B-V colour excess
703-710 F8.4 mag AvSandF Extinction
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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- 11 A11 --- Name Pulsar name (JHHMM+DDMMA)
13- 14 I2 h RAh Right ascension (J2000)
16- 17 I2 min RAm Right ascension (J2000)
19- 23 F5.2 s RAs Right ascension (J2000)
25 A1 --- DE- Declination sign (J2000)
26- 27 I2 deg DEd Declination (J2000)
29- 30 I2 arcmin DEm Declination (J2000)
32- 35 F4.1 arcsec DEs Declination (J2000)
37- 41 F5.3 Msun MWD White dwarf mass
43- 47 F5.3 Msun e_MWD ? Error on MWD
49- 53 F5.3 Msun MPSR ? Pulsar mass
55- 59 F5.3 Msun e_MPSR ? Error on MPSR
61- 68 F8.4 d Porb Orbital period
70-121 A52 --- Ref References
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History:
From electronic version of the journal
(End) Ana Fiallos [CDS] 09-Dec-2022