J/ApJS/249/18 The ZTF catalog of periodic variable stars (Chen+, 2020)
The Zwicky Transient Facility catalog of periodic variable stars.
Chen X., Wang S., Deng L., de Grijs R., Yang M., Tian H.
<Astrophys. J. Suppl. Ser., 249, 18 (2020)>
=2020ApJS..249...18C 2020ApJS..249...18C
ADC_Keywords: Stars, variable; Photometry; Optical
Keywords: Periodic variable stars ; Pulsating variable stars ;
Cepheid variable stars ; RR Lyrae variable stars ;
Delta Scuti variable stars ; Long period variable stars ;
Mira variable stars ; Eclipsing binary stars ; Galaxy structure ;
Distance indicators
Abstract:
The number of known periodic variables has grown rapidly in recent
years. Thanks to its large field of view and faint limiting magnitude,
the Zwicky Transient Facility (ZTF) offers a unique opportunity to
detect variable stars in the northern sky. Here, we exploit ZTF Data
Release 2 (DR2) to search for and classify variables down to
r∼20.6mag. We classify 781,602 periodic variables into 11 main types
using an improved classification method. Comparison with previously
published catalogs shows that 621,702 objects (79.5%) are newly
discovered or newly classified, including ∼700 Cepheids, ∼5000 RR
Lyrae stars, ∼15000 δ Scuti variables, ∼350,000 eclipsing
binaries, ∼100,000 long-period variables, and about 150,000 rotational
variables. The typical misclassification rate and period accuracy are
on the order of 2% and 99%, respectively. 74% of our variables are
located at Galactic latitudes, |b|<10°. This large sample of
Cepheids, RR Lyrae, δ Scuti stars, and contact (EW-type)
eclipsing binaries is helpful to investigate the Galaxy's disk
structure and evolution with an improved completeness, areal coverage,
and age resolution. Specifically, the northern warp and the disk's
edge at distances of 15-20kpc are significantly better covered than
previously. Among rotational variables, RS Canum Venaticorum and BY
Draconis-type variables can be separated easily. Our knowledge of
stellar chromospheric activity would benefit greatly from a
statistical analysis of these types of variables.
Description:
The Zwicky Transient Facility (ZTF) is a 48-inch Schmidt telescope
at the Palomar Observatory with a 47deg2 field of view.
ZTF DR2 contains data acquired between 2018 March and 2019 June,
covering a time span of around 470 days.
The photometry is provided in the g and r bands, with a uniform
exposure time of 30s per observation.
ZTF DR2 includes more than 1 billion stars, about half of which have
>20 epochs of observations. For the majority of stars located in the
northern Galactic plane, ZTF contains ∼150 epochs of observations.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 228 781602 ZTF variables catalog
table3.dat 120 1381527 ZTF suspected variables catalog
ztf2g.dat 75 89697393 g band single exposure photometry data
of variables from ZTF DR2
ztf2r.dat 75 89697393 r band single exposure photometry data
of variables from ZTF DR2
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Description of files:
ztf2g.csv = g band single exposure photometry data of variables from ZTF DR2
ztf2r.csv = r band single exposure photometry data of variables from ZTF DR2
Content: Seq, RAdeg, DEdeg, MJD, mag, e_mag, flag
See also:
II/351 : VISTA Magellanic Survey (VMC) catalog (Cioni+, 2011)
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
V/76 : Chromospherically Active Binaries (Strassmeier+ 1993)
V/128 : Chromospherically Active Binaries. Third version (Eker+, 2008)
J/AJ/119/1901 : ROTSE all-sky surveys for variable stars (Akerlof+, 2000)
J/AcA/51/221 : OGLE-II. Cepheids in IC 1613 (Udalski+, 2001)
J/AJ/127/861 : RR Lyrae in Draco dSph (Bonanos+, 2004)
J/ApJ/629/1055 : Evolution of close binary systems (Yakut+, 2005)
J/MNRAS/371/1405 : Variables in M33 (Hartman+, 2006)
J/AcA/58/163 : VI light curves of LMC classical Cepheids (Soszynski+, 2008)
J/AJ/140/328 : LMC High-amplitude delta Scuti stars (Garg+, 2010)
J/AJ/141/166 : HATNet variability survey of K and M dwarfs (Hartman+, 2011)
J/ApJ/727/53 : Red supergiant stars in the LMC. I. (Yang+, 2011)
J/ApJ/754/35 : Red supergiant stars in the SMC. II. (Yang+, 2012)
J/ApJ/765/154 : RR Lyrae stars in the Catalina Sky Survey (Drake+, 2013)
J/AJ/146/101 : LINEAR. III. Cat. of periodic variables (Palaversa+, 2013)
J/AcA/63/379 : OGLE-III var. stars in Gal. disk area (Pietrukowicz+, 2013)
J/ApJS/213/9 : Catalina Surveys periodic variable stars (Drake+, 2014)
J/MNRAS/442/2620 : VRI light curve of 5 eclipsing binaries (Zhang+, 2014)
J/AJ/152/129 : VR photometry for 914 stars in NGC 188 (Chen+, 2016)
J/A+A/591/A145 : VVV Survey outer bulge RRab stars (Gran+, 2016)
J/ApJ/832/176 : Classical Cepheids in MCs. I. LMC disk (Inno+, 2016)
J/A+A/605/A100 : VVV survey Galactic Bulge Pop. II Cepheids (Bhardwaj+, 2017)
J/MNRAS/469/3688 : CSS Periodic Variable Star Catalogue (Drake+, 2017)
J/A+A/604/A29 : MC Type II & anomalous Cepheids PL & PR (Groenewegen+, 2017)
J/MNRAS/472/808 : YJKs light curves of SMC Classical Cepheids (Ripepi+, 2017)
J/ApJ/844/L4 : PS1 RRab stars for tracing Virgo overdensity (Sesar+, 2017)
J/AJ/154/149 : LMC NIR synoptic survey. V. NIR phot. of Miras (Yuan+, 2017)
J/A+A/619/A51 : Type II Cepheids in the Galactic bulge (Braga+, 2018)
J/AJ/155/137 : RRLs in globulars. V.ω Cen NIR phot. (Braga+, 2018)
J/ApJ/859/140 : Multi-band magnitudes for W UMa EB* candidates (Chen+, 2018)
J/ApJS/237/28 : WISE catalog of periodic variable stars (Chen+, 2018)
J/AJ/156/241 : Variable stars measured by ATLAS (Heinze+, 2018)
J/AJ/156/130 : Cepheids in M31 - PAndromeda Cepheid sample (Kodric+, 2018)
J/ApJ/855/43 : Distant RR Lyrae stars discovered with HiTS (Medina+, 2018)
J/AJ/155/45 : Metal-rich RRc stars (Sneden+, 2018)
J/AcA/68/315 : OGLE Galactic Cepheids (Udalski+, 2018)
J/ApJ/852/78 : JHKs, WISE & Spitzer data of Galactic Cepheids (Wang+, 2018)
J/A+A/616/A175 : Red supergiant stars in the LMC. II. (Yang+, 2018)
J/AJ/156/112 : NIR Mira period-luminosity relations in M33 (Yuan+, 2018)
J/ApJ/870/115 : Distance modulus & Fe/H of RRLs in w Cen (Bono+, 2019)
J/A+A/622/A60 : Gaia DR2 misclassified RR Lyrae list (Clementini+, 2019)
J/A+A/623/A110 : Gaia DR2. Variable stars in CMD (Gaia Collaboration+, 2019)
J/AJ/158/105 : IR phot. of field RR Lyrae variable stars (Layden+, 2019)
J/A+A/625/A14 : Reclassification of Cepheids in the Gaia DR2 (Ripepi+, 2019)
J/other/Sci/365.478 : Milky Way classical Cepheids sample (Skowron+, 2019)
J/AJ/158/16 : Identification of RR Lyrae from the DES (Stringer+, 2019)
http://irsa.ipac.caltech.edu/Missions/ztf.html : ZTF on IRSA
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 22 A22 --- ID ZTF variables catalog identifier
24- 29 I6 --- Seq [1/781604] Internal source identifier
31- 39 F9.5 deg RAdeg Right Ascension in decimal degrees (J2000)
41- 49 F9.5 deg DEdeg Declination in decimal degrees (J2000)
51- 61 F11.7 d Per [0.03/973.5] Period
63- 68 F6.3 --- R21 [0/71] Amplitude ratio (a2/a1)
70- 74 F5.3 --- phi21 [3.14/9.5] Phase difference
(φ2-2*φ1)
76- 88 F13.7 d T0 HJD of minimum; HJD-2400000.5
90- 95 F6.3 mag gmag [11.7/22]?=0 Mean Palomar/ZTF g band magnitude
97-102 F6.3 mag rmag [11.2/21.4]?=0 Mean Palomar/ZTF r band
magnitude
104-116 F13.7 d Per-g [0.02/18340]?=0 Period determined in g band
118-130 F13.7 d Per-r [0.02/13242]?=0 Period determined in r band
132-135 I4 --- Ng [0/2084] Number of detections in g band
137-140 I4 --- Nr [0/3300] Number of detections in r band
142-147 F6.3 --- R21-g [0/96] Ratio of a2/a1 in g band
149-154 F6.3 --- R21-r [0/71] Ratio of a2/a1 in r band
156-160 F5.3 --- phi21-g [0/9.5] The φ2-2*φ1 in g band
162-166 F5.3 --- phi21-r [0/9.5] The φ2-2*φ1 in r band
168-173 F6.3 --- R2-g [-0.96/1] R-square in g band
175-180 F6.3 --- R2-r [-0.05/1] R-square in r band
182-186 F5.3 mag gAmp [0.006/8.11]?=0 Amplitude in g band
188-192 F5.3 mag rAmp [0.01/7]?=0 Amplitude in r band
194-201 F8.3 [-] log(FAP-g) [-226.2/0] False alarm probability in g band
203-210 F8.3 [-] log(FAP-r) [-223.2/0] False alarm probability in r band
212-216 A5 --- Type Variable type (1)
218-222 F5.3 mag Dmin-g [0/2.5] Minimum difference in g band
224-228 F5.3 mag Dmin-r [0/2.6] Minimum difference in r band
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Note (1): Variable type as follows:
BYDra = BY Draconis rotational variable (84697 occurrences)
CEP = Classical Cepheid (1262 occurrences)
CEPII = Type II Cepheid (358 occurrences)
DSCT = Low-amplitude δ Scuti star (16709 occurrences)
EA = EA-type eclipsing binary ( 49943 occurrences)
EW = EW-type eclipsing binary (369707 occurrences)
Mira = Mira variable (11879 occurrences)
RR = RRab Lyrae (32518 occurrences)
RRc = RRc Lyrae (13875 occurrences)
RSCVN = RS CVn (Canum Venaticorum) rotational variable (81393 occurrences)
SR = Semiregular variable (119261 occurrences)
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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- 22 A22 --- ID ZTF variables catalog identifier
24- 32 F9.5 deg RAdeg Right Ascension in decimal degrees (J2000)
34- 42 F9.5 deg DEdeg Declination in decimal degrees (J2000)
44- 49 F6.3 mag gmag [11.1/22.1]?=0 Mean Palomar/ZTF g band
magnitude
51- 56 F6.3 mag rmag [11.2/21.6]?=0 Mean Palomar/ZTF r band
magnitude
58- 68 F11.7 d Per-g [0.02/969]?=0 Period determined in g band
70- 80 F11.7 d Per-r [0.02/956]?=0 Period determined in r band
82- 86 F5.3 mag gAmp [0.01/6]?=0 Amplitude in g band
88- 92 F5.3 mag rAmp [0.008/5.7]?=0 Amplitude in r band
94- 97 I4 --- Ng [0/1220] Number of detections in g band
99-102 I4 --- Nr [0/1668] Number of detections in r band
104-111 F8.3 [-] log(FAP-g) [-124.4/0] False alarm probability in g band
113-120 F8.3 [-] log(FAP-r) [-115.5/0] False alarm probability in r band
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Byte-by-byte Description of file: ztf2[gr].dat
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Bytes Format Units Label Explanations
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1- 6 I6 --- Seq [1/781604] Running sequence number
8-18 E11.7 deg RAdeg Right ascension in decimal degrees (J2000)
20-30 E11.7 deg DEdeg [-20.8/80.3] Declination (J2000)
32-44 F13.7 d MJD [58197.15/58725.2] Modified Julian Date
46-55 F10.7 mag mag [9.97/22.63] Magnitude in g or r-band
57-70 E14.7 mag e_mag [-0.005/0.4] Uncertainty on the mag
72-75 I4 --- Flag [0/4628] Flag
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History:
From electronic version of the journal for tables
Light curves downloaded from doi:10.5281/zenodo.3886372 (csv files)
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 18-Sep-2020