J/ApJ/812/167 The ELM survey. VI. 11 new ELM WD binaries (Gianninas+, 2015)
The ELM survey.
VI. Eleven new double degenerates.
Gianninas A., Kilic M., Brown W.R., Canton P., Kenyon S.J.
<Astrophys. J., 812, 167 (2015)>
=2015ApJ...812..167G 2015ApJ...812..167G (SIMBAD/NED BibCode)
ADC_Keywords: Stars, white dwarf ; Stars, double and multiple ;
Radial velocities ; Stars, distances ; Stars, masses
Keywords: binaries: close; Galaxy: stellar content; gravitational waves;
supernovae: general; techniques: spectroscopic; white dwarfs
Abstract:
We present the discovery of 11 new double degenerate systems
containing extremely low-mass white dwarfs (ELM WDs). Our radial
velocity observations confirm that all of the targets have orbital
periods ≤1 day. We perform spectroscopic fits and provide a complete
set of physical and binary parameters. We review and compare recent
evolutionary calculations and estimate that the systematic uncertainty
in our mass determinations due to differences in the evolutionary
models is small (∼0.01M☉). Five of the new systems will merge
due to gravitational wave radiation within a Hubble time, bringing the
total number of merger systems found in the ELM Survey to 38. We
examine the ensemble properties of the current sample of ELM WD
binaries, including the period distribution as a function of effective
temperature, and the implications for the future evolution of these
systems. We also revisit the empirical boundaries of instability strip
of ELM WDs and identify new pulsating ELM WD candidates. Finally, we
consider the kinematic properties of our sample of ELM WDs and
estimate that a significant fraction of the WDs from the ELM Survey
are members of the Galactic halo.
Description:
We used the 6.5m MMT telescope equipped with the Blue Channel
spectrograph, the 200 inch Hale telescope equipped with the Double
spectrograph, the Kitt Peak National Observatory 4m telescope equipped
with the R-C spectrograph, and more recently with Kitt Peak Ohio State
Multi-Object Spectrograph (KOSMOS), to obtain spectroscopy of our 11
targets in several observing runs.
We have also been obtaining radial-velocity measurements for
candidates from other sources including the Large Sky Area
Multi-Object Spectroscopy Telescope (LAMOST).
Those 11 new Extremely low-mass white dwarf (ELM WD) binaries bring
the total of ELM WDs identified by the ELM Survey up to 73.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 131 11 New extremely low-mass white dwarf (ELM WD)
physical parameters
table4.dat 106 73 Extremely low-mass white dwarf (ELM WD)
physical parameters
table5.dat 100 73 Extremely low-mass white dwarf (ELM WD)
binary parameters
table6.dat 36 318 Radial velocity measurements for the new ELM WDs
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See also:
V/139 : The SDSS Photometric Catalog, Release 9 (Adelman-McCarthy+, 2012)
J/A+A/557/A19 : Mass & age of extreme low-mass white dwarfs (Althaus+, 2013)
J/ApJ/769/66 : The ELM survey. V. White dwarf binaries (Brown+, 2013)
J/MNRAS/413/1121 : SDSS WD-main sequence binaries. X (Rebassa-Mansergas+ 2011)
J/ApJ/743/138 : Spectroscopic survey of bright WDs (Gianninas+, 2011)
J/ApJ/731/17 : Low-mass stars in SDSS Stripe 82 (Becker+, 2011)
J/ApJ/730/67 : Radial velocities of low-mass white dwarfs (Brown+, 2011)
J/ApJ/723/1072 : The ELM survey. I. Low-mass white dwarfs (Brown+, 2010)
J/ApJS/156/47 : DA WDs from the Palomar Green Survey (Liebert+, 2005)
J/AJ/127/3034 : Proper-motion catalog combining USNO-B & SDSS (Munn+, 2004)
http://www.sdss.org/ : SDSS home page
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- Name SDSS abbreviated identifier (JHHMM+DDMM)
12- 13 I2 h RAh Hour of the Right Ascension (J2000)
15- 16 I2 min RAm Minute of the Right Ascension (J2000)
18- 22 F5.2 s RAs Second of the Right Ascension (J2000)
24 A1 --- DE- Sign of the Declination (J2000)
25- 26 I2 deg DEd Degree of Declination (J2000)
28- 29 I2 arcmin DEm Acrmin of Declination (J2000)
31- 35 F5.2 arcsec DEs Acrsec of Declination (J2000)
37- 41 I5 K Teff [8380/12300] Effective temperature (1)
43- 45 I3 K e_Teff [130/250] Uncertainty in Teff
47- 50 F4.2 [cm/s2] log(g) [4.9/7.2] Log surface gravity (1)
52- 55 F4.2 [cm/s2] e_log(g) [0.05/0.2] Uncertainty in log(g)
57- 61 F5.3 Msun Mass [0.15/0.29] Estimated mass
63- 67 F5.3 Msun e_Mass [0.01/0.03] Uncertainty in Mass
69- 74 F6.3 mag gmag [13.04/19.45] SDSS g band magnitude
76- 80 F5.3 mag e_gmag [0.01/0.03] Uncertainty in gmag
82- 86 F5.2 mag gMag [5.2/10.4] Absolute g band magnitude
88- 91 F4.2 mag e_gMag [0.2/0.6] Uncertainty in gMag
93- 97 F5.3 kpc Dist [0.1/1.7] Distance
99-103 F5.3 kpc e_Dist [0.02/0.4] Uncertainty in Dist
105-109 F5.3 Gyr tcool [0.1/3.7] Cooling time
111-115 F5.3 Gyr e_tcool [0.05/0.6] Uncertainty in tcool
117-123 F7.5 d Per [0.1/0.9] Period as in table 5;
column added by CDS
125-131 F7.5 d e_Per [0/0.009] Per uncertainty
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Note (1): Values are corrected for 3D effects according to
Tremblay et al. (2015ApJ...809..148T 2015ApJ...809..148T).
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- Name SDSS abbreviated identifier (JHHMM+DDMM)
12- 12 A1 --- f_Name [abc] Flag on SDSS (1)
14- 18 I5 K Teff [7890/34270] Effective temperature
20- 22 I3 K e_Teff Uncertainty in Teff
24- 27 F4.2 [cm/s2] log(g) [4.8/7.8] Log surface gravity
29- 32 F4.2 [cm/s2] e_log(g) Uncertainty in log(g)
34- 38 F5.3 Msun Mass [0.15/1.16] Estimated mass
40- 44 F5.3 Msun e_Mass [0.009/0.03] Uncertainty in Mass
46- 51 F6.4 Rsun Rad [0.01/0.28] Estimated radius
53- 58 F6.4 Rsun e_Rad [0.001/0.06] Uncertainty in Rad
60- 65 F6.3 mag gmag [13/20.6] SDSS g band magnitude
67- 71 F5.3 mag e_gmag [0.008/0.7] Uncertainty in gmag
73- 77 F5.2 mag gMag [4.5/11.3] Absolute g band magnitude
79- 82 F4.2 mag e_gMag [0.1/0.6] Uncertainty in gMag
84- 88 F5.3 kpc Dist [0.1/9.2] Distance
90- 94 F5.3 kpc e_Dist [0.01/1.9] Uncertainty in Dist
96-100 F5.3 Gyr tcool [0.001/7.7] Cooling time
102-106 F5.3 Gyr e_tcool [0.001/2.4] Uncertainty in tcool
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Note (1): Flag as follows:
a = NLTT 11748;
b = WD 0931+444.
c = LP 400-22.
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- Name SDSS abbreviated identifier (JHHMM+DDMM)
12- 18 F7.5 d Per [0.008/1.1]? Period
20- 26 F7.5 d e_Per [0/0.2]? Uncertainty in Per
28- 29 A2 --- l_K [≤] Limit flag on K
30- 34 F5.1 km/s K [24/617] Radial velocity amplitude
36- 38 F3.1 km/s e_K [0.5/9]? Uncertainty in K
40- 44 F5.3 Msun MF [0.005/1]? Mass function
46- 50 F5.3 Msun e_MF [0.001/0.09]? Uncertainty in MF
52- 53 A2 --- l_M2 [~≤>] Limit flag on M2
54- 57 F4.2 Msun M2 [0.07/1.3]? Secondary mass
59- 62 F4.2 Msun e_M2 [0.01/0.2]? Uncertainty in M2
64- 67 F4.2 Msun M2i60 [0.09/1.8]? Secondary mass assuming i=60 deg
69- 72 F4.2 Msun e_M2i60 [0.01/0.2]? Uncertainty in M2i60
74 A1 --- f_M2i60 [a] Flag on M2i60 (1)
76- 77 A2 --- l_tau [≤] Limit flag on tau
78- 83 F6.3 Gyr tau [0.001/13.3]? Merge time scale
85- 88 F4.2 Rsun Sep [0.1/4.2]? Binary separation
90- 93 F4.2 Rsun e_Sep [0.01/0.5]? Uncertainty in Sep
95-100 F6.2 [-] log(h) [-24.2/-21.5]? Log gravitational wave strain
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Note (1):
a = Eclipsing systems where we adopt M2 and inclination as determined from
eclipse modeling instead of assuming i=60 deg.
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Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- Name SDSS abbreviated identifier (JHHMM+DDMM)
12- 23 F12.7 d HJD Heliocentric Julian Date; HJD-2455000
25- 31 F7.2 km/s HRV [-324/403] Heliocentric radial velocity
33- 36 F4.1 km/s e_HRV [4/83] Uncertainty in HRV
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History:
From electronic version of the journal
References:
Brown et al. Paper I. 2010ApJ...723.1072B 2010ApJ...723.1072B Cat. J/ApJ/723/1072
Kilic et al. Paper II. 2011ApJ...727....3K 2011ApJ...727....3K
Brown et al. Paper III. 2012ApJ...744..142B 2012ApJ...744..142B
Kilic et al. Paper IV. 2012ApJ...751..141K 2012ApJ...751..141K
Brown et al. Paper V. 2013ApJ...769...66B 2013ApJ...769...66B Cat. J/ApJ/769/66
Brown et al. Paper VII. 2016ApJ...818..155B 2016ApJ...818..155B Cat. J/ApJ/818/155
Brown et al. Paper VIII. 2020ApJ...889...49B 2020ApJ...889...49B Cat. J/ApJ/889/49
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 09-Feb-2016