J/AcA/72/267 Variable star population in NGC 6819 (Sanjayan+, 2022)
Variable star population in the open cluster NGC 6819 observed by the
Kepler spacecraft.
Sanjayan S., Baran A.S., Nemeth P., Kinemuchi K.
<Acta Astron., 72, 267-295 (2022)>
=2022AcA....72..267S 2022AcA....72..267S (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, open ; Stars, variable ; Photometry ; Optical ;
Radial velocities ; Effective temperatures ; Abundances, [Fe/H]
Keywords: open clusters and associations: individual: NGC 6819 -
stars: variables: general
Abstract:
We present the list of variable stars we found in the Kepler
superstamp data covering approximately nine arcminutes from the
central region of NGC 6819. This is a continuation of our work
presented by Sanjayan et al. (2022AcA....72...77S 2022AcA....72...77S, Cat. J/AcA/72/77).
We classified the variable stars based on the variability type and we
established their cluster membership based on the available Gaia Data
Release 3 astrometry. Our search revealed 385 variable stars but only
128 were found to be cluster members. In the case of eclipsing and
contact binaries we calculated the mid-times of eclipses and derived
ephemerides. We searched for eclipse timing variation using the
observed minus calculated diagrams. Only five objects show significant
orbital period variation. We used isochrones calculated within theMESA
Isochrones and Stellar Tracks project and derived the average age
(2.54 Gyr), average distance (2.3 kpc) and iron content
[Fe/H]=-0.01(2), of NGC 6819. We confirm this distance by the one
derived from Gaia astrometry of the cluster members with membership
probabilities greater than 0.9.
Description:
We presented a search for variable stars in the Kepler superstamp data
of NGC 6819.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 150 17 List of binary stars that are cluster members
table2.dat 106 24 List of cluster members showing pulsations
table3.dat 113 82 List of cluster members showing rotational
variability
table4.dat 113 5 List of cluster members with unclassified
variability
table5.dat 144 34 List of binary stars in the field that are
not cluster members or no memberships derived
table6.dat 100 45 List of pulsators in the field that are not
cluster members or no memberships derived
table7.dat 101 136 List of rotational variables that are not
cluster members or no memberships derived
table8.dat 44 18 List of unclassified variables that are not
identified as cluster members in our analysis
table9.dat 52 24 List of equatorial coordinates that are
associated with the superstamp pixels showing
signal in their amplitude spectra
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See also:
I/350 : Gaia EDR3 (Gaia Collaboration, 2020)
V/133 : Kepler Input Catalog (Kepler Mission Team, 2009)
J/AcA/72/77 : Variable star population in NGC 6791 (Sanjayan+, 2022)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1 A1 --- Type [eaco] Type (G1)
3- 21 I19 --- GaiaEDR3 Gaia EDR3 identifier
22 A1 --- n_GaiaEDR3 [*] * for newly detected variables
24- 30 I7 --- KIC KIC identifier
32- 37 A6 --- n_KIC Note on KIC (G2)
39- 51 F13.9 d Porb Orbital period
53- 63 F11.9 d e_Porb ? Orbital period error
65 A1 --- n_Porb [e] Note on Porb (G5)
67- 80 F14.6 d T0 ?=- Time of minimum brightness (BJD)
82- 89 F8.6 d e_T0 ? Time of minimum brightness error
92- 97 F6.3 mag Gmag Gaia G magnitude
99-100 A2 --- CMD Position in the CMD (G3)
102-103 A2 --- HRD Position in the Teff, logg diagram (G3)
105-108 I4 K Teff ? Effective temperature
110-112 I3 K e_Teff ? Effective temperature error
115-119 F5.3 [cm/s2] logg ? Surface gravity
121-125 F5.3 [cm/s2] e_logg ? Surface gravity error
128-129 I2 km/s RV ? Radial velocity
131-132 I2 km/s e_RV ? Radial velocity error
135-140 F6.3 [-] [Fe/H] ? Metallicity
142-146 F5.3 [-] e_[Fe/H] ? Metallicity error
149-150 A2 -- Ref Source of the spectra (G4)
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1 A1 --- Type [1245] Type (G1)
3- 21 I19 --- GaiaEDR3 Gaia EDR3 identifier
22 A1 --- n_GaiaEDR3 [*] * for newly detected variables
24- 30 I7 --- KIC KIC identifier
32- 37 A6 --- n_KIC Note on KIC (G2)
39- 44 F6.3 mag Gmag Gaia G magnitude
46- 48 A3 --- CMD Position in the CMD (G3)
50- 52 A3 --- HRD Position in the Teff, logg diagram (G3)
54- 57 I4 K Teff ? Effective temperature
59- 60 I2 K e_Teff ? Effective temperature error
63- 66 F4.2 [cm/s2] logg ? Surface gravity
68- 71 F4.2 [cm/s2] e_logg ? Surface gravity error
74- 81 F8.4 km/s RV ? Radial velocity
83- 88 F6.4 km/s e_RV ? Radial velocity error
91- 96 F6.3 [-] [Fe/H] ? Metallicity
98-102 F5.3 [-] e_[Fe/H] ? Metallicity error
105-106 A2 --- Ref Source of the spectra (G4)
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Byte-by-byte Description of file:table[34].dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 I19 --- GaiaEDR3 Gaia EDR3 identifier
20 A1 --- n_GaiaEDR3 [*] * for newly detected variables
22- 28 I7 --- KIC ?=- KIC identifier
30- 36 A7 --- n_KIC Note on KIC (G2)
38- 44 F7.4 d Per Period
46- 51 F6.3 mag Gmag Gaia G magnitude
53- 56 A4 --- CMD Position in the CMD (G3)
58- 60 A3 --- HRD Position in the Teff, logg diagram (G3)
62- 65 I4 K Teff ? Effective temperature
67- 69 I3 K e_Teff ? Effective temperature error
72- 75 F4.2 [cm/s] logg ? Surface gravity
77- 80 F4.2 [cm/s] e_logg ? Surface gravity error
83- 89 F7.3 km/s RV ? Radial velocity
91- 95 F5.3 km/s e_RV ? Radial velocity error
98-103 F6.3 [-] [Fe/H] ? Metallicity
105-109 F5.3 [-] e_[Fe/H] ? Metallicity error
112-113 A2 --- Ref Source of the spectra (G4)
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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 A1 --- Type [eaco] Type (G1)
3- 21 I19 --- GaiaEDR3 Gaia EDR3 identifier
22 A1 --- n_GaiaEDR3 [*I] * for newly detected variables
24- 30 I7 --- KIC ?=- KIC identifier
32- 36 A5 --- n_KIC Note on KIC (G2)
37- 49 F13.9 d Porb ?=- Orbital period
52- 62 F11.9 d e_Porb ?=- Orbital period error
64 A1 --- n_Porb [es] Note on Porb (G5)
66- 79 F14.6 d T0 ?=- Time of minimum brightness
81- 89 F9.6 d e_T0 ? Time of minimum brightness error
92- 97 F6.3 mag Gmag Gaia G magnitude
99-103 I5 K Teff ? Effective temperature
105-107 I3 K e_Teff ? Effective temperature error
110-114 F5.3 [cm/s] logg ? Surface gravity
116-120 F5.3 [cm/s] e_logg ? Surface gravity error
123-125 I3 km/s RV ? Radial velocity
127-128 I2 km/s e_RV ? Radial velocity error
131-135 F5.2 [-] [Fe/H] ? Metallicity
137-140 F4.2 [-] e_[Fe/H] ? Metallicity
143-144 A2 --- Ref Source of the spectra (G4)
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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 A1 --- Type [123456] Type (G1)
3- 21 I19 --- GaiaEDR3 Gaia EDR3 identifier
22 A1 --- n_GaiaEDR3 [*] * for newly detected variables
24- 30 I7 --- KIC KIC identifier
32- 38 A7 --- n_KIC Note on KIC (G2)
39- 44 F6.3 mag Gmag Gaia G magnitude
46- 49 I4 K Teff ? Effective temperature
51- 53 I3 K e_Teff ? Effective temperature error
56- 60 F5.3 [cm/s2] logg ? Surface gravity
62- 66 F5.3 [cm/s2] e_logg ? Surface gravity error
68- 75 F8.4 km/s RV ? Radial velocity
77- 82 F6.4 km/s e_RV ? Radial velocity error
84- 90 F7.3 [-] [Fe/H] ? Metallicity
92- 96 F5.3 [-] e_[Fe/H] ? Metallicity error
99-100 A2 --- Ref Source of the spectra (G4)
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Byte-by-byte Description of file: table7.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 I19 --- GaiaEDR3 Gaia EDR3 identifier
20 A1 --- n_GaiaEDR3 [*iI] * for newly detected variables
22- 28 I7 --- KIC ?=- KIC identifier
30- 32 A3 --- n_KIC Note on KIC (G2)
34- 40 F7.4 d Per Period
42- 47 F6.3 mag Gmag ?=- Gaia G magnitude
49- 52 I4 K Teff ? Effective temperature
54- 56 I3 K e_Teff ? Effective temperature error
59- 63 F5.3 [cm/s2] logg ? Surface gravity
65- 69 F5.3 [cm/s2] e_logg ? Surface gravity error
71- 77 F7.3 km/s RV ? Radial velocity
79- 83 F5.3 km/s e_RV ? Radial velocity error
86- 91 F6.3 [-] [Fe/H] ? Metallicity
93- 97 F5.3 [-] e_[Fe/H] ? Metallicity error
100-101 A2 --- Ref Source of the spectra (G4)
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Byte-by-byte Description of file: table8.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 I19 --- GaiaEDR3 Gaia EDR3 identifier
20 A1 --- n_GaiaEDR3 [*i] * for newly detected variables
22- 28 I7 --- KIC ?=- KIC identifier
30 A1 --- n_KIC Note on KIC (G2)
32- 37 F6.4 d Per Period
39- 44 F6.3 mag Gmag Gaia G magnitude
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Byte-by-byte Description of file: table9.dat
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Bytes Format Units Label Explanations
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1 A1 --- New [*] * for new variable
2- 3 I2 h RAh Right ascension (J2000)
5- 6 I2 min RAm Right ascension (J2000)
8- 12 F5.2 s RAs Right ascension (J2000)
14 A1 --- DE- Declination sign (J2000)
15- 16 I2 deg DEd Declination (J2000)
18- 19 I2 arcmin DEm Declination (J2000)
21- 25 F5.2 arcsec DEs Declination (J2000)
27- 33 F7.4 d Per Period
35- 50 A16 --- Type Type
52 A1 --- Note [*] Note (1)
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Note (1): Note as follows:
* = associated with a variable star NGC 6819 SHLP 25645 and
reported by Street et al. (2002MNRAS.330..737S 2002MNRAS.330..737S)
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Global notes:
Note (G1): Type as follows:
e = eclipsing
a = active eclipsing
c = contact
o = outbursting
1 = gamma Dor
2 = solar-like
3 = sdBV
4 = semi-regular
5 = delta Scuti
6 = RRLyr/BLBoo
Note (G2): Note for data are available on the MAST as follows:
X = for no data,
L = for the LC data, numbers represent a total number of quarters
the date were taken in
S = for the SC data, numbers represent a total number of quarters
the date were taken in
Note (G3): Codes as follows:
MS = main sequence
RGB = red giant branch
BS = blue straggler
AGB = asymptotic giant branch
RC = red clump
HB = horizontal branch
EHB = extreme horizontal branch
MSTO = main sequence turn off
The + symbol indicates that not all five astrometric parameters
were used in the membership analysis.
Note (G4): Source of the spectra as follows:
1 = HECTOSPEC (https://oirsa.cfa.harvard.edu)
2 = NOT
3 = LAMOST (http://dr6.lamost.org)
4 = APO35 (https://www.apo.nmsu.edu)
5 = APOGEE (https://www.sdss.org/dr16/irspec)
* = indicates that the atmospheric parameters are derived
in this work
Note (G5): Note as follows:
e = significantly eccentric orbit
s = single-eclipse
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 13-Jun-2023