J/MNRAS/435/2077 Properties of Sirius-like binary systems (Holberg+, 2013)
Where are all the Sirius-like binary systems ?
Holberg J.B., Oswalt T.D., Sion E.M., Barstow M.A., Burleigh M.R.
<Mon. Not. R. Astron. Soc., 435, 2077-2091 (2013)>
=2013MNRAS.435.2077H 2013MNRAS.435.2077H
ADC_Keywords: Stars, double and multiple ; Stars, white dwarf ;
Stars, distances ; Binaries, orbits
Keywords: binaries: general - stars: distances - white dwarfs
Abstract:
Approximately 70% of the nearby white dwarfs appear to be single
stars, with the remainder being members of binary or multiple star
systems. The most numerous and most easily identifiable systems are
those in which the main-sequence companion is an M star, since even if
the systems are unresolved the white dwarf either dominates or is at
least competitive with the luminosity of the companion at optical
wavelengths. Harder to identify are systems where the non-degenerate
component has a spectral type earlier than M0 and the white dwarf
becomes the less luminous component. Taking Sirius as the prototype,
these latter systems are referred to here as 'Sirius like'. There are
currently 98 known Sirius-like systems. Studies of the local white
dwarf population within 20pc indicate that approximately 8 percent of
all white dwarfs are members of Sirius-like systems, yet beyond 20pc
the frequency of known Sirius-like systems declines to between 1 and 2
percent, indicating that many more of these systems remain to be
found. Estimates are provided for the local space density of
Sirius-like systems and their relative frequency among both the local
white dwarf population and the local population of A to K
main-sequence stars. The great majority of currently unidentified
Sirius-like systems will likely turn out to be closely separated and
unresolved binaries. Ways to observationally detect and study these
systems are discussed.
Description:
The properties of known resolved and unresolved 'Sirius-like system'
(SLSs) are presented.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 111 98 Known Sirius-Like System (SLSs)
table2.dat 93 98 Orbital properties
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See also:
J/A+A/299/621 : Is Sirius a triple star? (Benest+, 1995)
J/A+AS/136/293 : Sirius photographic observations (Jasinta+, 1999)
J/ApJS/126/461 : Equivalent Widths in the Spectrum of Sirius (Zhao+, 2000)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- WD White dwarf designation (HHMM+DDd)
10- 25 A16 --- Name Alternative name of the white dwarf
27- 40 A14 --- Name1 Luminous companion name (primary)
42- 47 A6 --- SpT WD spectral type
50- 57 A8 --- SpT1 MK spectral type of the companion
59 A1 --- l_Teff [~>] Limit flag on Teff
60- 64 I5 K Teff ?=- Effective temperature of the WD
66- 71 F6.3 mag Vmag ?=- V magnitude of the WD
73- 78 F6.3 mag Vmag1 ?=- V magnitude of the companion
79 A1 --- l_rho Limit flag on rho
80- 86 F7.3 arcsec rho [0.03/870]? Separation angle ρ
87 A1 --- n_rho [OU] U for unresolved, O for orbit
89- 95 F7.3 deg theta [0/360]?=- Position angle θ
97-103 F7.3 pc Dist [2.6/800]?=- Heliocentric distance
105-109 F5.2 pc e_Dist ?=- rms uncertainty on Dist
111 I1 --- Nc [2/5] Number of known components in the system
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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 White dwarf designation (HHMM+DDd)
10- 14 F5.3 Msun M [0.3/1.7]?=- Mass of the white dwarf
16- 21 F6.2 Msun M1 [0.5/700]?=- Mass of the companion
23 A1 --- l_ap Limit flag on ap
24- 31 F8.2 AU ap ?=- Projected physical separation
32 A1 --- l_a Limit flag on a
33- 42 F10.4 AU a ?=- Estimated semimajor axis
44 A1 --- l_P Limit flag on Per
45- 52 E8.3 yr P ?=- Estimated orbital period
54- 61 E8.3 uas/yr Dtheta ?=- Estimated orbital motion for resolved
WD-luminous star pairs (arcsec/Myr)
63 A1 --- l_dmu/dt Limit flag on dmu/dt
64- 71 E8.3 uas/yr2 dmu/dt ?=- Expected annual acceleration in angular
velocity of the luminous component
73 A1 --- l_dV/dt Limit flag on dV/dt
74- 81 E8.3 m/s/yr dV/dt ?=- Expected annual acceleration in radial
velocity of the luminous component
83- 93 A11 --- Com Comments
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 29-Sep-2014