J/PASP/130/H4203 Newly spectroscopically confirmed DB white dwarfs (Kong+, 2018)
Spectral feature extraction for DB white dwarfs through machine learning
applied to new discoveries in the SDSS DR12 and DR14.
Kong X., Luo A.-L., Li X.-R., Wang Y.-F., Li Y.-B., Zhao J.-K.
<Publ. Astron. Soc. Pac., 130, h4203 (2018)>
=2018PASP..130h4203K 2018PASP..130h4203K (SIMBAD/NED BibCode)
ADC_Keywords: Stars, white dwarf ; Radial velocities ; Effective temperatures ;
Photometry, ultraviolet
Keywords: catalogs - methods: data analysis - surveys - white dwarfs
Abstract:
Using a machine learning (ML) method, we mine DB white dwarfs (DBWDs)
from the Sloan Digital Sky Survey (SDSS) Data Release (DR) 12 and
DR14. The ML method consists of two parts: feature extraction and
classification. The least absolute shrinkage and selection operator
(LASSO) is used for the spectral feature extraction by comparing high
quality data of a positive sample group with negative sample groups.
In both the training and testing sets, the positive sample group is
composed of a selection of 300 known DBWDs, while the negative sample
groups are obtained from all types of SDSS spectra. In the space of
the LASSO detected features, a support vector machine is then employed
to build classifiers that are used to separate the DBWDs from the
non-DBWDs for each individual type. Depending on the classifiers, the
DBWD candidates are selected from the entire SDSS data set. After
visual inspection, 2808 spectra (2029 objects) are spectroscopically
confirmed. By checking the samples with the literature, there are 58
objects with 60 spectra that are newly identified, including a newly
discovered AM CVn. Finally, we measure their effective temperatures
(Teff), surface gravities (log g), and radial velocities, before
compiling them into a catalog.
Description:
We have spectroscopically identified 1999 DBWDs in the SDSS DR12 and
DR14, including 58 newly identified objects, using ML, i.e., LASSO and
SVM. A total of 176 DB objects from the literature are not included in
our catalog, Teff mostly varies around 11000K, and logg is fixed at
8.0.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table6.dat 155 2808 Newly spectroscopically confirmed DBWDs from
SDSS DR12 and DR14
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See also:
https://http://skyserver.sdss.org/DR12 : SDSS DR12 Home Page
https://http://skyserver.sdss.org/DR14 : SDSS DR14 Home Page
Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
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1- 19 A19 --- SDSS SDSS object name (JHHMMSS.ss+DDMMSS.s)
21- 35 A15 --- P-M-F SDSS Plate number-Modified Julian date-Fiber
37- 42 A6 --- Type Classification of objects derived from
ML method
44- 48 I5 km/s RVDB Radial velocity of each spectrum
50- 53 I4 km/s e_RVDB Radial velocity uncertainty of each spectrum
55- 59 I5 km/s RVM ?=-9999 Radial velocity of M companions
61- 65 I5 km/s e_RVM ?=-9999 Radial velocity uncertainty of
M companions
67- 71 I5 K Teff ?=-9999 Effective temperature
73- 77 I5 K e_Teff ?=-9999 Effective temperature
78- 82 F5.2 [cm/s2] logg ?=-9.99 Surface gravity
84- 89 F6.3 [cm/s2] e_logg ?=-9.999 Surface gravity
91- 95 F5.1 mag FUV ?=-99.9 Magnitude of FUV from GALEX
97-100 F4.1 mag e_FUV ?=-9.9 Magnitude uncertainty of FUV from GALEX
103-107 F5.1 mag NUV ?=-99.9 Magnitude of NUV from GALEX
109-112 F4.1 mag e_NUV ?=-9.9 Magnitude uncertainty of NUV from GALEX
116-119 F4.1 --- S/N Median S/N from catalog of SDSS DR14
121-124 F4.2 Msun Mass ?=9.99 Obtained from Bergeron & Gilles
Fontaine (2016) (1)
127-132 F6.1 Myr Age ?=-99.9 Obtained from Bergeron & Gilles
Fontaine (2016) (1)
134-155 A22 --- Ref ID of the literature (2)
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Note (1): Bergeron & Gilles Fontaine (2016, Synthetic Colors and Evolutionary
Sequences of Hydrogen- and Helium-Atmosphere White Dwarfs
http://www.astro.umontreal.ca/~bergeron/CoolingModels/)
Note (2): References as follows:
0 = newly identified in this paper
1 = Kleinman et al. (2013ApJS..204....5K 2013ApJS..204....5K, Cat. J/ApJS/204/5)
2 = Koester & Kepler (2005A&A...432.1025K 2005A&A...432.1025K)
3 = Kepler et al. (2015MNRAS.446.3078V 2015MNRAS.446.3078V)
4 = Kepler et al. (2016MNRAS.455.3413K 2016MNRAS.455.3413K, Cat. J/MNRAS/455/3413)
5 = Atlee & Gould (2007ApJ...664...53A 2007ApJ...664...53A, Cat. J/ApJ/664/53)
6 = Eisenstein et al. (2006ApJS..167...40E 2006ApJS..167...40E, Cat. J/ApJS/167/40)
7 = Croom et al. (2004MNRAS.349.1397C 2004MNRAS.349.1397C, Cat. VII/241)
8 = Croom et al. (2001MNRAS.322L..29C 2001MNRAS.322L..29C, Cat. VII/223)
9 = Rebassa-Mansergas et al. (2010MNRAS.402..620R 2010MNRAS.402..620R, Cat. J/MNRAS/402/620)
10 = West et al. (2008AJ....135..785W 2008AJ....135..785W, Cat. J/AJ/135/785)
11 = Girven et al. (2011MNRAS.417.1210G 2011MNRAS.417.1210G, Cat. J/MNRAS/417/1210)
12 = Stepanian (2005RMxAA..41..155S 2005RMxAA..41..155S, Cat. VII/276)
13 = Bicay et al. (2000A&AS..147..169B 2000A&AS..147..169B, Cat. J/A+AS/147/169)
14 = Gentile Fusillo et al. (2015MNRAS.448.2260G 2015MNRAS.448.2260G, Cat. J/MNRAS/448/2260)
15 = Levitan et al. (2015MNRAS.446..391L 2015MNRAS.446..391L)
16 = Drake et al. (2014ApJS..213....9D 2014ApJS..213....9D, Cat. J/ApJS/213/9)
17 = Vennes et al. (2011MNRAS.410.2095V 2011MNRAS.410.2095V)
18 = Rau et al. (2010ApJ...708..456R 2010ApJ...708..456R)
19 = Carter et al. (2013MNRAS.429.2143C 2013MNRAS.429.2143C, Cat. J/MNRAS/429/2143)
20 = Jura & Xu (2012AJ....143....6J 2012AJ....143....6J)
21 = Girven et al. (2012ApJ...749..154G 2012ApJ...749..154G)
22 = Bergeron et al. (2011ApJ...737...28B 2011ApJ...737...28B)
23 = Zuckerman et al. (2010ApJ...722..725Z 2010ApJ...722..725Z)
24 = Voss et al. (2007A&A...470.1079V 2007A&A...470.1079V, Cat. J/A+A/470/1079)
25 = Koester et al. (2005A&A...432.1025K 2005A&A...432.1025K)
26 = McCook & Sion (1999ApJS..121....1M 1999ApJS..121....1M, Cat. B/wd )
27 = Bradley (2000BaltA...9..485B 2000BaltA...9..485B)
28 = Bradley (1998BaltA...7..355B 1998BaltA...7..355B)
29 = Lepine & Shara (2005AJ....129.1483L 2005AJ....129.1483L, Cat. I/298)
30 = Stepanian et al. (2005RMxAA..41..155S 2005RMxAA..41..155S, Cat. VII/276)
31 = Stark & Wade (2003AJ....126.1455S 2003AJ....126.1455S, Cat. J/AJ/126/1455)
32 = Calcaferro et al. (2017A&A...600A..73C 2017A&A...600A..73C)
33 = Kleinman et al. (2004ApJ...607..426K 2004ApJ...607..426K, Cat. J/ApJ/607/426)
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 09-Oct-2020