J/AJ/165/79 Catalogs for Berkeley 68 and Stock 20 (Yontan, 2023)
An Investigation of Open Clusters Berkeley 68 and Stock 20 Using CCD.
Yontan T.
<Astron. J., 165, 79 (2023)>
=2023AJ....165...79Y 2023AJ....165...79Y
ADC_Keywords: Clusters, open; Photometry, UBV; Parallaxes, trigonometric;
Proper motions
Keywords: Open star clusters
Abstract:
We performed detailed photometric and astrometric analyses of the open
star clusters Berkeley68 and Stock20. This was based on ground-based
CCD UBV photometric data complemented by space-based Gaia Data Release
3 (DR3) photometry and astrometry. A total of 198 and 51 stars were
identified as likely cluster members for Berkeley68 and Stock20,
respectively. Two-color diagrams were used to derive the reddening and
photometric metallicity for each cluster. The reddening for Berkeley68
and Stock20 is E(B-V)=0.520±0.032mag and 0.400±0.048mag,
respectively. Photometric metallicity [Fe/H] is -0.13±0.08dex for
Berkeley68 and -0.01±0.06dex for Stock20. Keeping as constant
reddening and metallicity, we determined the distance moduli and ages
of the clusters through fitting isochrones to the UBV and Gaia-based
color-magnitude diagrams. Photometric distances are d=3003±165pc
for Berkeley68 and 2911±216pc for Stock20. The cluster ages are
2.4±0.2Gyr and 50±10Myr for Berkeley68 and Stock20,
respectively. Present-day mass function slopes were found to be
Γ=1.38±0.71 and Γ=1.53±0.39 for Berkeley68 and
Stock20, respectively. These values are compatible with the value of
Salpeter. The relaxation times were estimated as 32.55 and 23.17Myr
for Berkeley68 and Stock20, respectively. These times are less than
the estimated cluster ages, indicating that both clusters are
dynamically relaxed. Orbit integration was carried out only for
Berkeley68 since radial velocity data were not available for Stock20.
Analysis indicated that Berkeley68 was born outside the solar circle
and belongs to the thin-disk component of the Milky Way.
Description:
CCD UBV observations of stars located through the cluster regions of
Berkeley68 and Stock20 were made on 2018 November 6 and 2016 October
8, respectively. We used the T100 100cm//10 Ritchey-Chretien
telescope at the TUBITAK National Observatory (TUG) in Turkey.
Images were taken with a back-illuminated 4kx4k pixel CCD. The
image scale is 0.31"/pix, with a total field of view of21.5"x21.5".
Objects:
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RA (2000) DE Designation(s)
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04 44 12.72 +42 08 02.4 Berkeley 68 = C 0441+419
00 25 16.32 +62 37 26.4 Stock 20 = C 0022+623
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table5.dat 146 6414 The catalogs for Berkeley 68 and Stock 20
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See also:
I/337 : Gaia DR1 (Gaia Collaboration, 2016)
J/A+AS/133/387 : NGC 1817 and NGC 1807 proper motions (Balaguer-Nunnez+ 1998)
J/AJ/115/592 : VI photometry of NGC 2157 (Fischer+, 1998)
J/A+A/329/101 : Masses of Pleiades members (Raboud+ 1998)
J/A+AS/141/491 : Chemical composition of halo and disk stars (Nissen+, 2000)
J/AJ/137/4186 : UBVRI standards around celestial equator (Landolt, 2009)
J/AJ/141/92 : BVI photometry of 10 distant open clusters (Janes+, 2011)
J/A+A/543/A156 : Milky Way global survey of star clusters (Kharchenko+, 2012)
J/MNRAS/436/1465 : Star clusters distances and extinctions (Buckner+, 2013)
J/MNRAS/430/3350 : Proper motions and membership in NGC 3766 (Yadav+, 2013)
J/MNRAS/453/1095 : NGC 6866 UBVRI photometry (Bostanci+, 2015)
J/other/ApSS/355.267 : NGC 6811 CCD UBVRI photometry (Yontan+, 2015)
J/other/ApSS/361.126 : NGC 6819 CCD UBV photometry (Ak+, 2016)
J/other/ASpR/58.1900 : NGC 225 CCD UBV photometry (Bilir+, 2016)
J/AJ/153/99 : Galactic outer disk field toward Tombaugh 1 (Carraro+, 2017)
J/A+A/618/A93 : Gaia DR2 open clusters in Milky Way (Cantat-Gaudin+, 2018)
J/A+A/618/A59 : Gaia DR2 new nearby open clusters (Castro-Ginard+, 2018)
J/MNRAS/479/5491 : Absolute parameters of 509 main-sequence stars (Eker+, 2018)
J/A+A/619/A155 : Open cluster kinematics with Gaia DR2 (Soubiran+, 2018)
J/A+A/624/A126 : New open clusters Perseus direction (Cantat-Gaudin+, 2019)
J/A+A/627/A35 : New open clusters Galactic anticentre (Castro-Ginard+, 2019)
J/ApJS/245/32 : Newly identified star clusters in Gaia DR2 (Liu+, 2019)
J/MNRAS/487/2385 : Distances and ages of 150 open clusters (Monteiro+, 2019)
J/A+A/640/A1 : Portrait Galactic disc (Cantat-Gaudin+, 2020)
J/A+A/635/A45 : 570 new open cluster in Galactic disc (Castro-Ginard+, 2020)
J/A+A/640/A127 : Open cluster properties with Gaia and LAMOST (Zhong+, 2020)
J/other/ApSS/366.68 : Czernik 2 & NGC 7554 CCD UBV photometry (Akbulut+, 2021)
J/MNRAS/504/356 : Updated parameters of 1743 open clusters (Dias+, 2021)
J/A+A/652/A102 : 3794 open clusters parameters (Hao+, 2021)
J/other/RAA/21.93 : 74 new open clusters found in Gaia DR2 (He+, 2021)
J/A+A/651/A104 : Spiral arms Gaia EDR3 (Poggio+, 2021)
J/AJ/162/146 : Kinematic & photometry of King 11, Gaia EDR3 (Sariya+, 2021)
J/A+A/647/A19 : 3D Kinematics and age of OCs (Tarricq+, 2021)
J/AN/342/538 : Frolov 1 and NGC 7510 CCD UBV photometry (Yontan+, 2021)
J/AJ/163/191 : Photometry & astrometry in NGC1664 and NGC6939 (Koc+, 2022)
J/other/RMxAA/58.333 : NGC 1193 and NGC 1798 CCD UBV photometry (Yontan+, 2022)
Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- Cluster Cluster identifier Berkeley 68 (B68) or
Stock 20 (S20)
5- 8 I4 --- ID [1/3548] Stellare identifier within the cluster
10 I1 h RAh [0/4] Hour of Right Ascension (J2000)
12- 13 I2 min RAm Minute of Right Ascension (J2000)
15- 19 F5.2 s RAs Second of Right Ascension (J2000)
21 A1 --- DE- [+] Sign of the Declination (J2000)
22- 23 I2 deg DEd [41/62] Degree of Declination (J2000)
25- 26 I2 arcmin DEm Arcminute of Declination (J2000)
28- 32 F5.2 arcsec DEs Arcsecond of Declination (J2000)
34- 39 F6.3 mag Vmag [9.2/22.9] Apparent V band magnitude
41- 45 F5.3 mag e_Vmag [0.001/0.5] Uncertainty in Vmag
47- 52 F6.3 mag U-B [-3.42/2.05]? The (U-B) color
54- 58 F5.3 mag e_U-B [0.001/0.6]? Uncertainty in U-B
60- 65 F6.3 mag B-V [-1.38/3.97] The (B-V) color
67- 71 F5.3 mag e_B-V [0.001/0.8] Uncertainty in B-V
73- 78 F6.3 mag Gmag [9.07/21.7]? Gaia DR3 apparent G band color
80- 84 F5.3 mag e_Gmag [0.003/0.05]? Uncertainty in Gmag
86- 91 F6.3 mag BP-RP [-0.19/4.06]? Gaia DR3 Blue-Red passband color
93- 97 F5.3 mag e_BP-RP [0.005/0.74]? Uncertainty in BP-RP
99-106 F8.3 mas/yr pmRA [-85/218]? Gaia DR3 proper motion along RAcosDE
108-112 F5.3 mas/yr e_pmRA [0.008/2]? Uncertainty in pmRA
114-121 F8.3 mas/yr pmDE [-174/37.3]? Gaia DR3 proper motion along DE
123-127 F5.3 mas/yr e_pmDE [0.009/2]? Uncertainty in pmDE
129-135 F7.3 mas plx [-3.52/24.1]? Gaia DR3 parallax
137-141 F5.3 mas e_plx [0.009/2]? Uncertainty in plx
143-146 F4.2 --- Prob [0/1]? Membership probability
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 01-Jun-2023