J/AJ/160/252 ZZ Ceti white dwarfs and candidates in Gaia survey (Vincent+, 2020)
Searching for ZZ Ceti white dwarfs in the Gaia survey.
Vincent O., Bergeron P., Lafreniere D.
<Astron. J., 160, 252 (2020)>
=2020AJ....160..252V 2020AJ....160..252V
ADC_Keywords: Stars, white dwarf; Stars, variable; Photometry, ugriz;
Proper motions; Stars, masses; Effective temperatures
Keywords: White dwarf stars ; ZZ Ceti stars ; Pulsating variable stars ;
Fundamental parameters of stars
Abstract:
The Gaia satellite recently released parallax measurements for ∼260000
high-confidence white dwarf candidates, allowing for precise
measurements of their physical parameters. By combining these
parallaxes with Pan-STARRS and u-band photometry, we measured the
effective temperature and stellar mass for all white dwarfs in the
Northern Hemisphere within 100pc of the Sun, and identified a sample
of ZZ-Ceti white dwarf candidates within the so-called instability
strip. We acquired high-speed photometric observations for 90
candidates using the PESTO camera attached to the 1.6m telescope at
the Mont-Megantic Observatory. We report the discovery of 38 new
ZZ-Ceti stars, including two very rare ultramassive pulsators. We also
identified five possibly variable stars within the strip, in addition
to 47 objects that do not appear to show any photometric variability.
However, several of those could be variable with an amplitude below
our detection threshold, or could be located outside the instability
strip due to errors in their photometric parameters. In the light of
our results, we explore the trends of the dominant period and
amplitude in the M--Teff plane, and briefly discuss the question of
the purity of the ZZ-Ceti instability strip (i.e., a region devoid of
non-variable stars).
Description:
We obtained time series photometry using the PESTO camera on the 1.6m
telescope at the Mont-Megantic Observatory (Quebec). Our survey
spanned over 68 nights from 2018 July to 2020 August. We used a 10s
exposure time for most observations, occasionally increasing to 30s
for fainter objects. We initially used a g'-filter but eventually
switched to using no filter to maximize the target flux and
signal-to-noise ratio.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 193 191 The ZZ Ceti Candidates
table3.dat 117 43 New ZZ Ceti white dwarfs and properties of possible
pulsators
table4.dat 101 65 Non Observed to Vary (NOV) candidate properties
ref.dat 58 13 References used
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See also:
B/simbad : Simbad objects catalogue (M.Wenger 2000)
III/210 : Spectroscopically Identified White Dwarfs (McCook+, 1999)
III/235 : Spectroscopically Identified White Dwarfs (McCook+, 2008)
V/147 : The SDSS Photometric Catalogue, Release 12 (Alam+, 2015)
I/337 : Gaia DR1 (Gaia Collaboration, 2016)
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
J/ApJ/631/1100 : Atmospheric parameters of DA white dwarfs (Gianninas+, 2005)
J/ApJ/643/402 : Cool white dwarfs in the solar neighborhood (Kawka+, 2006)
J/A+A/447/173 : 3D-kinematics white dwarfs from SPY. II. (Pauli+, 2006)
J/A+A/505/441 : UVES/VLT spectra of white dwarfs (Koester+, 2009)
J/MNRAS/407/681 : Proper motions FBS blue stellar objects (Mickaelian+, 2010)
J/ApJ/743/138 : Spectroscopic survey bright white dwarfs (Gianninas+, 2011)
J/ApJS/204/5 : SDSS DR7 white dwarf catalog (Kleinman+, 2013)
J/AJ/146/34 : IR photometry of DA white dwarfs from LAMOST (Zhang+, 2013)
J/ApJ/794/35 : Binary white dwarfs atmospheric parameters (Gianninas+,2014)
J/ApJ/815/63 : SDSS wide double white dwarfs spectroscopy (Andrews+, 2015)
J/MNRAS/454/2787 : LAMOST DR2 white dwarfs (Guo+, 2015)
J/ApJS/219/19 : Census nearby white dwarfs from SUPERBLINK (Limoges+, 2015)
J/ApJS/232/23 : 27 pulsating DA WDs follow-up observations (Hermes+, 2017)
J/A+A/616/A10 : 46 open clusters GaiaDR2 diagrams (Gaia Collaboration, 2018)
J/A+A/623/A110 : Gaia DR2. Variable stars in CMD (Gaia Collaboration+, 2019)
J/MNRAS/482/4570 : Gaia DR2 white dwarf candidates (Gentile Fusillo+, 2019)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 19 I19 --- Gaia Gaia DR2 identifier
21- 28 F8.4 deg RAdeg [2.23/360] Right Ascension (J2015.5)
30- 37 F8.4 deg DEdeg [-19.4/87.3] Declination (J2015.5)
39- 44 F6.3 mas plx [10/35.4] Parallax
46- 50 F5.3 mas e_plx [0.02/0.5] Uncertainty in plx
52- 59 F8.3 mas/yr pmRA [-261/248] Proper motion in RA
61- 65 F5.3 mas/yr e_pmRA [0.04/0.6] Uncertainty in pmRA
67- 74 F8.3 mas/yr pmDE [-335/199] Proper motion in DE
76- 80 F5.3 mas/yr e_pmDE [0.04/0.5] Uncertainty in pmDE
82- 87 F6.3 mag Gmag [14.2/18.4] Gaia DR2 mean G band magnitude
89- 94 F6.3 mag Gbmag [14.1/18.3] Gaia DR2 blue passband magnitude
96-101 F6.3 mag Grmag [14.2/18.3] Gaia DR2 red passband magnitude
103-108 F6.3 mag gmag [14.1/18.3] Pan-STARRS g band magnitude
110-115 F6.3 mag e_gmag [0.003/18.3] Uncertainty in gmag
117-122 F6.3 mag rmag [14.3/18.4] Pan-STARRS r band magnitude
124-128 F5.3 mag e_rmag [0/0.02] Uncertainty in rmag
130-135 F6.3 mag imag [14.5/18.6] Pan-STARRS i band magnitude
137-141 F5.3 mag e_imag [0.001/0.07] Uncertainty in imag
143-148 F6.3 mag zmag [14.7/18.8] Pan-STARRS z band magnitude
150-154 F5.3 mag e_zmag [0.001/0.02] Uncertainty in zmag
156-161 F6.3 mag ymag [14.9/18.9] Pan-STARRS y band magnitude
163-167 F5.3 mag e_ymag [0/0.07] Uncertainty in ymag
169-174 F6.3 mag uCmag [0/17.8] Canada-France Imaging Survey u band
magnitude
176-180 F5.3 mag e_uCmag [0/0.003] Uncertainty in umag
182-187 F6.3 mag uSmag [0/18.1] SDSS u band magnitude
189-193 F5.3 mag e_uSmag [0/0.03] Uncertainty in uSmag
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- WD White dwarf identification
12 A1 --- f_WD [*] Indicate a possible pulsator (5 occurrences)
14- 32 I19 --- Gaia Gaia DR2 identification
34- 35 I2 h RAh [0/23] Hour of right ascension (J2015.5)
37- 38 I2 min RAm Minute of right ascension (J2015.5)
40- 44 F5.2 s RAs Second of right ascension (J2015.5)
46 A1 --- DE- [-/+] Sign of declination (J2015.5)
47- 48 I2 deg DEd Degree of declination (J2015.5)
50- 51 I2 arcmin DEm Arcminute of declination (J2015.5)
53- 57 F5.2 arcsec DEs Arcsecond of declination (J2015.5)
59- 62 I4 s Per [102/1579] Dominant period
64- 67 F4.1 % Ampl [0.2/38.5] Dominant amplitude
69- 72 F4.2 % e_Ampl [0.07/6.1] 5σ error on Ampl
74 A1 --- l_FAP [<] Limite flag on FAP
76- 79 F4.1 % FAP [0.1/42] False alarm probability
81- 85 I5 K Teff [10311/12513] Effective temperature
87- 89 I3 K e_Teff [39/206] Error in Teff
91- 95 F5.3 Msun Mass [0.5/1.2] Mass
97-101 F5.3 Msun e_Mass [0.005/0.02] Error on Mass
103-106 F4.1 mag Gmag [15/17.8] Gaia G magnitude
108-111 F4.1 mag umag [16.4/17.4]? SDSS or CFIS u magnitude
113 A1 --- r_umag [ab] Reference for umag (1)
115-117 A3 --- DAref Literature identifying the object as a DA
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Note (1): References as follows:
a = SDSS photometry; Alam+, 2015, V/147 (21 occurrences)
b = Canada-France Imaging Survey; Ibata+, 2017ApJ...848..128I 2017ApJ...848..128I
(1 occurrence)
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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 --- WD White dwarf identification
12- 30 I19 --- Gaia Gaia DR2 identification
32- 33 I2 h RAh [0/23] Hour of right ascension (J2015.5)
35- 36 I2 min RAm Minute of right ascension (J2015.5)
38- 42 F5.2 s RAs Second of right ascension (J2015.5)
44 A1 --- DE- [±] Sign of declination (J2015.5)
45- 46 I2 deg DEd Degree of declination (J2015.5)
48- 49 I2 arcmin DEm Arcminute of declination (J2015.5)
51- 55 F5.2 arcsec DEs Arcsecond of declination (J2015.5)
57- 59 A3 --- Pstrip Indicating whether or not the object is located
within the photometric instability strip
61- 65 I5 K Teff [10416/13313] Effective temperature
67- 69 I3 K e_Teff [29/249] Error in Teff
71- 75 F5.3 Msun Mass [0.45/1.21] Mass
77- 81 F5.3 Msun e_Mass [0.004/0.02] Error on Mass
83- 86 F4.1 mag Gmag [14.2/18.3] Gaia G magnitude
88- 91 F4.1 mag umag [15.7/18]? SDSS or CFIS u magnitude
93 A1 --- r_umag Reference used for umag (1)
95- 97 F3.1 % Prec [0.6/7.8] Prercision
99-101 A3 --- DAref Literature identifying the object as a DA
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Note (1): References as follows:
a = SDSS photometry; Alam+, 2015, V/147 (27 occurrences)
b = Canada-France Imaging Survey; Ibata+, 2017ApJ...848..128I 2017ApJ...848..128I
(2 occurrences)
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Byte-by-byte Description of file: ref.dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- Ref Reference code
5- 21 A17 --- Autor Main autor of the reference
23- 41 A19 --- BIB BIBcode
43- 58 A16 --- Cat. Vizier catalog
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 01-Feb-2021