J/A+A/513/L7 Post common envelope binaries from SDSS. VIII (Schreiber+, 2010)
Post common envelope binaries from SDSS.
VIII: Evidence for disrupted magnetic braking.
Schreiber M.R., Gaensicke B.T., Rebassa-Mansergas A., Nebot Gomez-Moran A.,
Southworth J., Schwope A.D., Mueller M., Papadaki C., Pyrzas S., Rabitz A.,
Rodriguez-Gil P., Schmidtobreick L., Schwarz R., Tappert C., Toloza O.,
Vogel J., Zorotovic M.
<Astron. Astrophys. 513, L7 (2010)>
=2010A&A...513L...7S 2010A&A...513L...7S
ADC_Keywords: Stars, double and multiple ; Stars, white dwarf ; Stars, dwarfs ;
Radial velocities ; Stars, masses
Keywords: binaries: close - magnetic fields - stars: low mass - white dwarfs
Abstract:
We present the results of a large survey of post common envelope
binaries (PCEBs) among white dwarf/main sequence (WDMS) binaries from
the SDSS that allows to determine the fraction of PCEBs as a function
of secondary star mass and therewith to ultimately test the disrupted
magnetic braking hypothesis. We obtained multiple spectroscopic
observations spread over at least two nights of 589 WDMS binaries.
Using mostly the NaI 8183.27,8194.81 absorption doublet we determined
the corresponding radial velocities.
Description:
The file rv.dat contains the name of the WDMS binary, the time of the
spectroscopic observation and the corresponding radial velocity. Using
a spectral decomposition method we derived estimates of the stellar
parameters and the distance to the system listed in sy.dat. This file
also contains the statistical significance of the measured radial
velocity variations derived from the velocities given in rv.dat.
The stellar parameters have been taken from Rebassa-Mansergas et al.
(2010, Cat. J/MNRAS/402/620) and Nebot-Gomez Moran (2010, A&A in
prep.). The spectral decomposition method is described in
Rebassa-Mansergas et al. (2007, Cat. J/MNRAS/382/1377). Some radial
velocities have been published earlier in Schreiber et al.
(2008A&A...484..441S 2008A&A...484..441S)
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
sy.dat 111 670 Stellar parameters derived for the WDMS binaries
by spectral decomposition of the SDSS spectrum
and the statistical significance of radial
velocity variations
rv.dat 57 3306 Multiple radial velocities of the 670 WDMS
binaries derived from 3308 spectra
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See also:
J/MNRAS/382/1377 : SDSS WD main-sequence binaries (Rebassa-Mansergas+, 2007)
J/MNRAS/402/620 : SDSS WD main-sequence binaries (Rebassa-Mansergas+, 2010)
Byte-by-byte Description of file: sy.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Nsp Number of spectra available for this system
4- 7 A4 --- --- [SDSS]
8- 16 A9 --- Name Name of the WDMS binary (HHMM+DDMM)
18- 22 A5 --- Type Type of WDMS binary (1)
24- 27 F4.2 solMass Mwd ?=- Mass of the white dwarf (1)
29- 32 F4.2 solMass e_Mwd ?=- Uncertainty (1 sigma) of Mwd estimate
34- 37 I4 pc d ?=- Distance to the WDMS binary as measured to
the white dwarf
39- 42 I4 pc e_d ?=- Uncertainty of the distance estimate
44- 47 F4.2 --- SpT Spectral sub-type of the secondary star
49- 53 F5.3 solMass Msec Mass of the secondary (main sequence) star
55- 59 I5 K Twd ?=- White dwarf temperature
61- 66 F6.2 km/s RVvar Peak to peak radial velocity variation
68- 73 F6.2 km/s e_RVvar Error of peak to peak radial velocity
variation
74- 85 E12.9 --- Signi [0/1] Statistical significance of radial
velocity variation
87 I1 --- pc [0/4] PCEB (post common envelope binaries)
candidate (3 or >4σ) or wide WDMS
candidate (2)
89- 92 A4 --- --- [SDSS]
93-111 A19 --- SDSS SDSS designation (JHHMMSS.ss+DDMMSS.s)
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Note (1): type of binary, generally a denegerate (DA, DB, DC, WD) and
a low-mass (M) star. "LARP" stands for "Low Accretion Rate Polars",
i.e. pre-cataclysmic variables containing a magnetic white dwarf.
Note (2): In some cases the white dwarf type is DC, DB, or unknown and we
could not estimate the white dwarf mass and the distance to the system.
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Byte-by-byte Description of file: rv.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- --- [SDSS]
5- 13 A9 --- Name WDMS name (HHMM+DDMM)
15- 26 F12.4 d HJD ? Heliocentric Julian date (1)
28- 34 F7.2 km/s RV Radial velocity
36- 41 F6.2 km/s e_RV Radial velocity uncertainty (1 sigma)
43- 57 A15 --- Tel Telescope/Instrument (2)
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Note (1): In some cases the date at which an SDSS spectrum (i.e. the
combined SDSS spectrum from individual exposures) has been taken
could not be reconstructed. This is indicated by a 0.00000 in the
corresponding column.
Note (2): The abbreviations for the telescopes we used are the following:
CA3.5 = RV based on spectra taken with the Calar Alto 3.5m Telescope
SDSS = RV derived from an SDSS spectrum or directly from the
individual sub-exposures
WHT = RV based on spectra taken with the William Herschel Telescope
GS = RV based on spectra taken at Gemini South
ESO = RV based on spectra taken with ESO VLT/FORS2
NTT = RV based on spectra taken with ESO NTT
MAG = RV based on spectra taken with the Magellan Telescopes at LCO
* "Na" after the abbreviation indicates in all cases that the Rvels
were measured from the NaI doublet, Ha from the Halpha emission.
* If nothing is indicated it implies that the RV were measured also
from the NaI doublet.
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Acknowledgements:
Matthias Schreiber,
References:
Rebassa-Mansergas et al., Paper I 2007MNRAS.382.1377R 2007MNRAS.382.1377R (J/MNRAS/382/1377)
Schreiber et al, Paper II 2008A&A...484..441S 2008A&A...484..441S
Rebassa-Mansergas et al., Paper III 2008MNRAS.390.1635R 2008MNRAS.390.1635R
Nebot Gomez-Moran et al., Paper IV 2009A&A...495..561N 2009A&A...495..561N
Pyrzas et al., Paper V 2009MNRAS.394..978P 2009MNRAS.394..978P
Schwope et al., Paper VI 2009A&A...500..867S 2009A&A...500..867S
Rebassa-Mansergas et al., Paper VII 2010MNRAS.402..620R 2010MNRAS.402..620R (J/MNRAS/402/620)
(End) Patricia Vannier [CDS] 19-Mar-2010