J/MNRAS/497/130 Gaia white dwarfs within 40pc. I (Tremblay+, 2020)
Gaia white dwarfs within 40 pc. I. Spectroscopic observations of new candidates.
Tremblay P.-E., Hollands M.A., Gentile Fusillo N.P., McCleery J.,
Izquierdo P., Gansicke B.T., Cukanovaite E., Koester D., Brown W.R.,
Charpinet S., Cunningham T., Farihi J., Giammichele N., Van Grootel V.,
Hermes J.J., Hoskin M.J., Jordan S., Kepler S.O., Kleinman S.J.,
Manser C.J., Marsh T.R., De Martino D., Nitta A., Parsons S.G.,
Pelisoli I., Raddi R., Rebassa-Mansergas A., Ren J.-J., Schreiber M.R.,
Silvotti R., Toloza O., Toonen S., Torres S.
<Mon. Not. R. Astron. Soc., 497, 130-145 (2020)>
=2020MNRAS.497..130T 2020MNRAS.497..130T (SIMBAD/NED BibCode)
ADC_Keywords: Stars, white dwarf ; Stars, nearby ; Spectroscopy ; Optical
Keywords: stars: statistics - white dwarfs - solar neighbourhood
Abstract:
We present a spectroscopic survey of 230 white dwarf candidates within
40pc of the Sun from the William Herschel Telescope and Gran
Telescopio Canarias. All candidates were selected from Gaia Data
Release 2 (DR2) and in almost all cases, had no prior spectroscopic
classifications. We find a total of 191 confirmed white dwarfs and 39
main-sequence star contaminants. The majority of stellar remnants in
the sample are relatively cool (<Teff≥6200K), showing either hydrogen
Balmer lines or a featureless spectrum, corresponding to 89 DA and 76
DC white dwarfs, respectively. We also recover two DBA white dwarfs
and 9-10 magnetic remnants. We find two carbon-bearing DQ stars and
14 new metal-rich white dwarfs. This includes the possible detection
of the first ultra-cool white dwarf with metal lines. We describe
three DZ stars for which we find at least four different metal
species, including one that is strongly Fe- and Ni-rich, indicative of
the accretion of a planetesimal with core-Earth composition. We find
one extremely massive (1.31±0.01M☉) DA white dwarf showing
weak Balmer lines, possibly indicating stellar magnetism. Another
white dwarf shows strong Balmer line emission but no infrared excess,
suggesting a low-mass sub-stellar companion. A high spectroscopic
completeness (>99 per cent) has now been reached for Gaia DR2 sources
within 40-pc sample, in the Northern hemisphere (δ>0° and
located on the white dwarf cooling track in the Hertzsprung-Russell
diagram. A statistical study of the full northern sample is presented
in a companion paper (McCleery et al., Paper II, 2020MNRAS.499.1890M 2020MNRAS.499.1890M,
Cat. J/MNRAS/499/1890).
Description:
We selected white dwarf candidates from the catalogue of Gentile
Fusillo et al. (2019MNRAS.482.4570G 2019MNRAS.482.4570G, cat. J/MNRAS/482/4570) with
Plx>25mas±1σ as the only requirement, resulting in 1233
sources, among which 184 are low probability candidates (PWD<0.75).
We observed a total of 230 white dwarf candidates at the Observatorio
del Roque de los Muchachos, both with the Intermediate-dispersion
Spectrograph and Imaging System (ISIS) on the WHT and the Optical
System for Imaging and low-Resolution Integrated Spectroscopy (OSIRIS)
on the GTC.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 89 191 Spectral types and parameters of the
white dwarf sample
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See also:
J/ApJS/219/19 : Nearby white dwarfs from SUPERBLINK (Limoges+, 2015)
J/MNRAS/482/4570 : Gaia DR2 white dwarf candidates (Gentile Fusillo+, 2019)
J/MNRAS/499/1890 : Gaia white dwarfs within 40pc. II. (McCleery+, 2020)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1 A1 --- n_WDJ [*] Note on WJD (1)
3- 21 A19 --- WDJ WDJ name, HHMMSS.ss+DDMMSS.s (J2000)
23- 27 A5 --- SpType Spectral type (2)
28- 32 I5 K Teff3D ?=- 3D spectro effective temperature
34- 36 I3 K e_Teff3D ? 3D spectro effective temperature error (3)
38- 41 F4.2 [cm/s2] logg3D ?=- 3D spectro surface gravity
43- 46 F4.2 [cm/s2] e_logg3D ? 3D spectro surface gravity error (3)
48- 52 I5 K TeffG ?=- Gaia DR2 effective temperature
54- 57 I4 K e_TeffG ? Gaia DR2 effective temperature error (3)
59- 62 F4.2 [cm/s2] loggG ?=- Gaia DR2 surface gravity
64- 67 F4.2 [cm/s2] e_loggG ? Gaia DR2 surface gravity error (3)
69- 73 I5 K TeffP ?=- Pan-STARRS effective temperature
75- 77 I3 K e_TeffP ? Pan-STARRS effective temperature error (3)
79- 82 F4.2 [cm/s2] loggP ?=- Pan-STARRS surface gravity
84- 87 F4.2 [cm/s2] e_loggP ? Pan-STARRS surface gravity error (3)
89 A1 --- Note Note (4)
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Note (1): * for objects where the parallax value is below 25mas but for
which 40-pc membership is still possible within 1σ.
Note (2): For all photometric fits, we have used either pure-H (DA, DAZ, DAH,
and DC cooler than 5000K), pure-He (He-rich DA and DC in the range
5000<Teff<7000K), or mixed log(H/He)=-5 model atmospheres
(DZ, DZH, DZA, DQ, DBA, and DC warmer than 7000K).
Note (3): All quoted uncertainties represent the intrinsic fitting errors.
Note (4): Note as follows:
a = also in Scholz et al. (2018A&A...619A..31S 2018A&A...619A..31S)
b = double degenerate candidate
c = also in Landstreet & Bagnulo (2020A&A...634L..10L 2020A&A...634L..10L)
d = wide double white dwarf
e = DAH: in Limoges et al. (2015ApJS..219...19L 2015ApJS..219...19L)
f = likely He-rich white dwarf
g = DA in Limoges et al. (2015ApJS..219...19L 2015ApJS..219...19L)
h = D: in Leggett et al. (2018ApJS..239...26L 2018ApJS..239...26L)
i = FAST spectrum has poor S/N, Balmer line fit uncertain
j = main-sequence star in Reid et al. (2004AJ....128..463R 2004AJ....128..463R)
k = WD in Greenstein (1984ApJ...276..602G 1984ApJ...276..602G)
l = DC in Oswalt & Strunk (1994, American Astronomical Society May Meeting
Abstracts, 28.09)
m = DA in Motch et al. (1998A&AS..132..341M 1998A&AS..132..341M)
n = also in Landstreet & Bagnulo (2019A&A...623A..46L 2019A&A...623A..46L)
o = DC: in Limoges et al. (2015ApJS..219...19L 2015ApJS..219...19L)
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History:
From electronic version of the journal
References:
McCleery et al., Paper II 2020MNRAS.499.1890M 2020MNRAS.499.1890M, Cat. J/MNRAS/499/1890
(End) Patricia Vannier [CDS] 09-Feb-2021