J/ApJ/850/34 3000-25000Å spectroscopy of nearby M dwarfs (Bar+, 2017)
A spectroscopic search for white dwarf companions to 101 nearby M dwarfs.
Bar I., Vreeswijk P., Gal-Yam A., Ofek E.O., Nelemans G.
<Astrophys. J., 850, 34 (2017)>
=2017ApJ...850...34B 2017ApJ...850...34B
ADC_Keywords: Stars, M-type; Spectral types; Stars, double and multiple;
Spectra, optical; Spectra, infrared; Stars, distances
Keywords: binaries: general ; stars: late-type ; white dwarfs
Abstract:
Recent studies of the stellar population in the solar neighborhood
(<20pc) suggest that there are undetected white dwarfs (WDs) in
multiple systems with main-sequence companions. Detecting these hidden
stars and obtaining a more complete census of nearby WDs is important
for our understanding of stellar and galactic evolution, as well as
the study of explosive phenomena. In an attempt to uncover these
hidden WDs, we present intermediate resolution spectroscopy over the
wavelength range of 3000-25000Å of 101 nearby M dwarfs (dMs),
observed with the Very Large Telescope X-Shooter spectrograph. For
each star we search for a hot component superimposed on the dM
spectrum. X-Shooter has excellent blue sensitivity and thus can reveal
a faint hot WD despite the brightness of its red companion. Visual
examination shows no clear evidence of a WD in any of the spectra. We
place upper limits on the effective temperatures of WDs that may still
be hiding by fitting dM templates to the spectra and modeling the WD
spectra. On average our survey is sensitive to WDs hotter than about
5300K. This suggests that the frequency of WD companions of
Teff≳5300K with separation of the order of ≲50 au among the local dM
population is <3% at the 95% confidence level.
Description:
The observations were performed with the X-Shooter spectrograph
mounted at the Kueyen unit of the Very Large Telescope (UT2), operated
by the European Southern Observatory (ESO) on Cerro Paranal in Chile
(Program IDs 095_D-0949(A) --2015 Apr to Sept-- and
096_D-0963(A), PI: Paul Vreeswijk --2015 Oct to 2016 Feb).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 46 101 Obtained results of spectral analysis
table2.dat 98 101 Observed M dwarfs
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See also:
B/eso : ESO Science Archive Catalog (ESO, 1991-2018)
B/wds : The Washington Visual Double Star Catalog (Mason+ 2001-2014)
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
J/PASP/110/863 : A Stellar Spectral Flux Library: 1150 - 25000 A (Pickles 1998)
J/ApJS/133/413 : BVRIJHK photometry of cool white dwarfs (Bergeron+, 2001)
J/ApJ/571/512 : Distances of white dwarf stars (Holberg+, 2002)
J/AJ/128/426 : Subdwarfs in the SDSS (West+, 2004)
J/AJ/132/1221 : VJHK and SDSS photometry of DA white dwarfs (Holberg+, 2006)
J/AJ/135/1225 : Parameters of the local white dwarfs (Holberg+, 2008)
J/AJ/137/3358 : Speckle interferometry of massive stars (Mason+, 2009)
J/AJ/138/1681 : WD within 20pc of the Sun (Sion+, 2009)
J/ApJS/190/1 : A survey of stellar families (Raghavan+, 2010)
J/PASP/122/885 : Gliese cat. star/2MASS cross identifications (Stauffer+, 2010)
J/ApJ/730/128 : Spectroscopy of DA WD from the SDSS-DR4 (Tremblay+, 2011)
J/ApJS/204/5 : SDSS DR7 white dwarf catalog (Kleinman+, 2013)
J/A+A/565/A117 : X-Shooter Spectral Library (XSL). DR1 (Chen+, 2014)
J/MNRAS/437/1216 : VAST Survey. A-type stars multiplicity (De Rosa+, 2014)
J/A+A/568/A9 : 300-2500nm flux calibration reference spectra (Moehler+, 2014)
J/ApJ/817/1 : Palomar/MSU & SDSS-DR7 M dwarfs with GALEX obs. (Jones+, 2016)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Name Name
10- 17 A8 --- Temp Template Name
19- 23 I5 K RSS [3750/10500]? Template temperature limit
from Residual Sum of Squares (RSS) score
25- 28 I4 K Env [5000/9500]? Template temperature limit
from fit residuals envelope
30- 33 I4 K Blue [3750/8500] Template temperature limit from
total blue flux
35- 36 A2 --- Act Activity (1)
38- 46 A9 arcsec Sep Companion separation from WDS (2)
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Note (1): Activity -
B+Ca = Balmer and CaII emission lines;
Ca = CaII lines only;
D = Double emission lines (Balmer and CaII).
Note (2): Companion separations, in arcseconds, from the WDS catalog, listed
for targets where at least one companion is closer than 2.5 arcseconds.
Multiple companion separations delineate by "+". The separation of
NN3129 is given a value "?" as it was listed as binary in Shkolnik+
(2010ApJ...716.1522S 2010ApJ...716.1522S) but no separation was reported.
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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 --- Name Name
10- 11 I2 h RAh Hour of Right Ascension (J2000)
13- 14 I2 min RAm Minute of Right Ascension (J2000)
16- 20 F5.2 s RAs Second of Right Ascension (J2000)
22- 22 A1 --- DE- Sign of the Declination (J2000)
23- 24 I2 deg DEd Degree of Declination (J2000)
26- 27 I2 arcmin DEm Arcminute of Declination (J2000)
29- 32 F4.1 arcsec DEs Arcsecond of Declination (J2000)
34- 42 A9 --- SpT MK Spectral Type (M2 to M7) from SIMBAD
44- 48 F5.2 mag Vmag [10.4/16] Apparent V band magnitude
from Gliese+, 1991, V/70
50- 54 F5.2 pc Dist [2.9/20] Distance from Gliese+, 1991, V/70
56- 65 A10 "Y/M/D" Obs.date Observation date
67- 74 A8 "h:m:s" Obs.time Observation time, UTC
76- 80 F5.3 --- Airmass [1/2.3] Airmass
82- 84 F3.1 arcsec Seeing [0.3/1.6] Seeing
86- 88 I3 s UVB [60/360] UVB Exposure
90- 92 I3 s VIS [30/300] VIS Exposure
94- 94 I1 --- nNIR [4] NIR Exposure, coadds
96- 98 I3 s NIR [10/100] NIR Exposure
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 20-Jun-2018