J/MNRAS/462/2295 25 parsec local white dwarf population (Holberg+, 2016)
The 25 parsec local white dwarf population.
Holberg J.B., Oswalt T.D., Sion E.M., McCook G.P.
<Mon. Not. R. Astron. Soc., 462, 2295-2318 (2016)>
=2016MNRAS.462.2295H 2016MNRAS.462.2295H (SIMBAD/NED BibCode)
ADC_Keywords: Stars, white dwarf ; Stars, nearby ; Photometry, UBVRI ;
Photometry, infrared ; Stars, masses ; Stars, distances
Keywords: binaries: close - white dwarfs
Abstract:
We have extended our detailed survey of the local white dwarf
population from 20 to 25pc, effectively doubling the sample volume,
which now includes 232 stars. In the process, new stars within 20 pc
have been added, a more uniform set of distance estimates as well as
improved spectral and binary classifications are available. The
present 25pc sample is estimated to be about 68 per cent complete
(the corresponding 20pc sample is now 86 per cent complete). The
space density of white dwarfs is unchanged at 4.8±0.5x10-3pc-3.
This new study includes a white dwarf mass distribution and luminosity
function based on the 232 stars in the 25pc sample. We find a
significant excess of single stars over systems containing one or more
companions (74 per cent versus 26 per cent). This suggests
mechanisms that result in the loss of companions during binary system
evolution. In addition, this updated sample exhibits a pronounced
deficiency of nearby 'Sirius-like' systems. 11 such systems were
found within the 20pc volume versus only one additional system found
in the volume between 20 and 25pc. An estimate of white dwarf birth
rates during the last ∼8Gyr is derived from individual remnant
cooling ages. A discussion of likely ways new members of the local
sample may be found is provided.
Description:
Table 1 presents the basic properties of the 232 WDs in the LS25
identified by WD number and alternate name.
Existing multiband photometry for each star in our LS25 sample is
listed in Table 2.
Table 3 provides the adapted distances calculated from the
trigonometric parallaxes (see Table 1) or photometric distances
calculated from the adapted Teff and logg photometry in Table 2.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 92 226 25pc White Dwarf sample
table2.dat 120 228 UBVRI + JHK photometry and uncertainties
table3.dat 74 227 Physical properties
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See also:
B/wd : Spectroscopically identified white dwarfs (McCook+, 2014)
I/238 : Yale Trigonometric Parallaxes, Fourth Edition (van Altena+ 1995)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 2 A2 --- --- [WD]
3- 10 A8 --- WD The MS99 (Cat. B/wd) white dwarf number (G1)
11- 13 A3 --- m_WD Multiplicity index on WD
17- 30 A14 --- OName Alternate ID
33- 42 A10 --- SpType The WD spectral type (2)
44- 49 F6.3 mag Vmag Measured or computed V magnitude (3)
52- 57 F6.2 mas plx ? Observed trigonometric parallax (4)
60- 64 F5.2 mas e_plx ? rms uncertainty on plx
68- 69 I2 --- r_plx ? Parallax reference (5)
76- 77 A2 --- System [sbml dd] System (6)
84 I1 --- N Number of WDs in system.
92 A1 --- Note [a] a = stars discussed in the Appendix A
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Note (2): adopted spectral type for each star following the MS99 conventions and
adjusting the numerical temperature index in each spectral type to match our
adopted temperature.
Note (3): Where no V-band photometry exists, effective V magnitudes are
calculated from alternate photometric data and the spectroscopic Teff and logg
estimates.
Note (4): The measured trigonometric parallax and uncertainty are given for the
stars, if such measurements exist. The three primary sources for these
parallax data are the Yale Parallax Catalogue (van Altena, Lee & Hoffleit,
1994, Cat. I/238), the revised Hipparchos Catalogue (van Leeuwen, 2007,
Cat. I/311) and several publications of The Research Consortium on
Nearby Stars (RECONS, http://www.recons.org). Weighted mean parallaxes from
the webpage created by J.P. Subasavage (http://www.denseproject.com) are also
used. In some cases, the listed parallaxes are those of the common proper
motion companion star.
Note (5): References as follows:
1 = van Altena et al. (1994, Cat. I/238)
2 = van Leeuwen (2007, Cat. I/311)
3 = Subasavage et al. (2009AJ....137.4547S 2009AJ....137.4547S)
4 = Smart et al. (2003A&A...404..317S 2003A&A...404..317S)
5 = Gatewood & Coban (2009AJ....137..402G 2009AJ....137..402G)
6 = Lepine et al. (2009AJ....137.4109L 2009AJ....137.4109L)
7 = Jao et al. (2014AJ....147...21J 2014AJ....147...21J)
8 = Dahn et al. (1982AJ.....87..419D 1982AJ.....87..419D)
9 = Ducourant et al. (2007A&A...470..387D 2007A&A...470..387D)
Note (6): Systems as follows:
s = single
b = binary
m = multiple
dd = double degenerate
sl = Sirius-like systems
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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- 8 A8 --- WD The MS99 (Cat. B/wd) white dwarf number (G1)
9- 10 A2 --- m_WD Multiplicity index on WD
12- 17 F6.3 mag Umag ? U magnitude
19- 24 F6.4 mag e_Umag ? rms uncertainty on U magnitude
26- 31 F6.3 mag Bmag ? B magnitude
33- 38 F6.4 mag e_Bmag ? rms uncertainty on B magnitude
40- 46 F7.4 mag Vmag ? V magnitude
48- 53 F6.4 mag e_Vmag ? rms uncertainty on V magnitude
55- 60 F6.3 mag Rmag ? R magnitude
62- 67 F6.4 mag e_Rmag ? rms uncertainty on R magnitude
69- 74 F6.3 mag Imag ? I magnitude
76- 81 F6.4 mag e_Imag ? rms uncertainty on I magnitude
83- 88 F6.3 mag Jmag ? J magnitude
90- 94 F5.3 mag e_Jmag ? rms uncertainty on J magnitude
96-101 F6.3 mag Hmag ? H magnitude
103-107 F5.3 mag e_Hmag ? rms uncertainty on H magnitude
109-114 F6.3 mag Kmag ? K magnitude
116-120 F5.3 mag e_Kmag ? rms uncertainty on K magnitude
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- WD The MS99 (Cat. B/wd) white dwarf number (G1)
9- 11 A3 --- m_WD Multiplicity index on WD
12- 16 I5 K Teff Adopted effective temperature
18- 21 I4 K e_Teff rms uncertainty on Teff
23- 26 F4.2 [cm/s2] logg Adopted log surface gravity
28- 31 F4.2 [cm/s2] e_logg rms uncertainty on logg
33- 36 A4 --- Comp Photospheric composition
38- 42 F5.3 Msun Mass Estimated mass
44- 48 F5.3 Msun e_Mass rms uncertainty on Mass
50- 54 F5.2 pc Dist Distance
56- 60 F5.2 pc e_Dist rms uncertainty on Dist
62 A1 --- Meth [ps] Method by which distance was determined
(p = parallax and s = spectroscopic)
64- 68 F5.2 mag mbol Estimated bolometric magnitude
70- 74 F5.2 Gyr Age Estimated cooling age
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Global notes:
Note (G1): If the star is not in the current online version of the Villanova
Catalogue of Spectroscopically identified White Dwarfs (McCook & Sion,
1999ApJS..121....1M 1999ApJS..121....1M, Cat. B/wd, hereafter MS99) a preliminary WD number
is computed.
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 01-Feb-2018