J/AJ/163/191 Photometry and astrometry in NGC 1664 and NGC 6939 (Koc+, 2022)
A Photometric and Astrometric Study of the Open Clusters NGC 1664 and NGC 6939.
Koc S., Yontan T., Bilir S., Canbay R., Ak T., Banks T., Ak S., Paunzen E.
<Astron. J., 163, 191 (2022)>
=2022AJ....163..191K 2022AJ....163..191K
ADC_Keywords: Clusters, open; Photometry, VRI; Colors; Proper motions;
Parallaxes, trigonometric
Keywords: Open star clusters ; Star clusters ; Galaxy kinematics ;
Stellar kinematics ; Hertzsprung Russell diagram
Abstract:
This study calculated astrophysical parameters, as well as kinematic
and galactic orbital parameters, of the open clusters NGC1664 and
NGC6939. The work is based on CCD ultraviolet, blue, and visual (UBV)
and Gaia photometric and astrometric data from ground- and space-based
observations. Considering Gaia Early Data Release 3 (EDR3) astrometric
data, we determined membership probabilities of stars located in both
of the clusters. We used two-color diagrams to determine the E(B-V)
color excesses for NGC1664 and NGC6939 as 0.190±0.018 and
0.380±0.025mag, respectively. Photometric metallicities for the
two clusters were estimated as [Fe/H]=-0.10±0.02dex for NGC1664
and as [Fe/H]=-0.06±0.01dex for NGC6939. Using the reddening and
metallicity calculated in the study, we obtained distance moduli and
ages of the clusters by fitting parsec isochrones to the
color-magnitude diagrams based on the most likely member stars.
Isochrone fitting distances are 1289±47pc and 1716±87pc, which
coincide with ages of 675±50Myr and 1.5±0.2Gyr for NGC1664 and
NGC6939, respectively. We also derived the distances to the clusters
using Gaia trigonometric parallaxes and compared these estimates with
the literature. We concluded that the results are in good agreement
with those given by the current study. Present-day mass function
slopes were calculated as Γ=-1.22±0.33 and
Γ=-1.18±0.21 for NGC1664 and NGC6939, respectively, which
are compatible with the Salpeter slope. Analyzes showed that both of
clusters are dynamically relaxed. The kinematic and dynamic orbital
parameters of the clusters were calculated, indicating that the
birthplaces of the clusters are outside the solar circle.
Description:
The ground-based CCD UBV observations of NGC1664 and NGC6939 were made
using the 100cm Ritchey-Chretien telescope (T100) of the TUBITAK
National Observatory (TUG) located in Turkey. The UBV images were
taken using a Spectral Instruments CCD camera operating at -100°C.
The CCD camera is equipped with a back illuminated 4kx4k pixel CCD,
with a scale of 0.31"/pixel. This results in an unvignetted field of
view of 21.5x21.5' on the telescope.
Objects:
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RA (2000) DE Designation(s)
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04 51 03 +43 40.6 NGC1664 = NGC 1664
20 31 40 +60 39.2 NGC6939 = NGC 6939
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table5.dat 152 5854 The catalogs for NGC 1664 and NGC 6939
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See also:
B/ocl : Optically visible open clusters and Candidates (Dias+ 2002-2015)
I/317 : The PPMXL Catalog (Roeser+ 2010)
I/352 : Distances to 1.47 billion stars in Gaia EDR3 (Bailer-Jones+, 2021)
J/A+AS/133/387 : NGC 1817 and NGC 1807 proper motions (Balaguer-Nunnez+ 1998)
J/A+AS/141/491 : Chemical composition of halo and disk stars (Nissen+, 2000)
J/A+A/438/1163 : Catalogue of Open Cluster Data (COCD) (Kharchenko+, 2005)
J/AJ/134/1216 : Abundance of NGC7142, 6939, & IC4756 stars (Jacobson+, 2007)
J/AJ/137/4186 : UBVRI standards around celestial equator (Landolt, 2009)
J/MNRAS/393/272 : Spectroscopy of red giants, 12 open clusters (Warren+, 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/AJ/145/107 : Zr, Ba, La, & Eu abund. in 19 open cluster (Jacobson+, 2013)
J/A+A/558/A53 : Milky Way global survey star clusters II (Kharchenko+, 2013)
J/MNRAS/430/3350 : Proper motions and membership in NGC 3766 (Yadav+, 2013)
J/A+A/564/A79 : Proper motions of open clusters from UCAC4 (Dias+, 2014)
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/A+A/593/A116 : Open clusters within 1.8 kpc of the Sun (Joshi+, 2016)
J/A+A/585/A101 : Milky Way global survey star clusters. V (Kharchenko+, 2016)
J/AJ/153/99 : Galactic outer disk; field toward Tombaugh1 (Carraro+, 2017)
J/A+A/600/A106 : RAVE open cluster pairs, groups & complexes (Conrad+, 2017)
J/MNRAS/470/3937 : 1876 open clusters multimembership catalog (Sampedro+, 2017)
J/AJ/153/57 : Shape parameters 154 Galactic open clusters (Zhai+, 2017)
J/A+A/618/A93 : Gaia DR2 open clusters in Milky Way (Cantat-Gaudin+, 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/623/A108 : Age of 269 GDR2 open clusters (Bossini+, 2019)
J/A+A/623/A80 : Open clusters in APOGEE and GALAH surveys (Carrera+, 2019)
J/MNRAS/490/1821 : Abundances stars in 18 open clusters (Casamiquela+, 2019)
J/ApJS/245/32 : Newly identified star clusters in Gaia DR2 (Liu+, 2019)
J/A+A/633/A99 : GaiaDR2 open clusters in Milky Way II (Cantat-Gaudin+, 2020)
J/A+A/640/A1 : Portrait Galactic disc (Cantat-Gaudin+, 2020)
J/A+A/635/A45 : 570 new open clusters in Galactic disc (Castro-Ginard+,2020)
J/AJ/159/199 : OCCAM. IV. Open cluster abundances APOGEE DR16 (Donor+,2020)
J/MNRAS/504/356 : Updated parameters of 1743 open clusters (Dias+, 2021)
J/A+A/654/A20 : Plx zero-point offset from Gaia EDR3 (Groenewegen, 2021)
J/A+A/652/A102 : 3794 open clusters parameters (Hao+, 2021)
J/MNRAS/507/1699 : Blue straggler stars open clusters with Gaia (Jadhav+, 2021)
J/A+A/647/A19 : 3D Kinematics and age of OCs (Tarricq+, 2021)
Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Cluster Cluster identifier
10- 13 I4 --- ID [1/3735] Sequential number within the cluster
15- 16 I2 h RAh [4/20] Hour of Right ascension (J2000)
18- 19 I2 min RAm Minute of Right ascension (J2000)
21- 25 F5.2 s RAs Second of Right ascension (J2000)
27 A1 --- DE- [+] Sign of the Declination sign (J2000)
28- 29 I2 deg DEd [43/60] Degree of Declination (J2000)
31- 32 I2 arcmin DEm Arcminute of Declination (J2000)
34- 38 F5.2 arcsec DEs Arcsecond of Declination (J2000)
40- 45 F6.3 mag Vmag [9.95/22.3] Apparent Johnson V magnitude
47- 51 F5.3 mag e_Vmag [0.001/0.6]? rms uncertainty on Vmag
53- 58 F6.3 mag U-B [-4.86/2.11]? Johnson U-B color index
60- 64 F5.3 mag e_U-B [0.001/0.3]? rms uncertainty on U-B
66- 71 F6.3 mag B-V [-1.19/4.41]? Johnson B-V color index
73- 77 F5.3 mag e_B-V [0.001/0.8]? rms uncertainty on B-V
79- 84 F6.3 mag Gmag [9.34/21.7]? Apparent Gaia EDR3 G magnitude
86- 90 F5.3 mag e_Gmag [0.003/0.09]? rms uncertainty on Gmag
92- 97 F6.3 mag BP-RP [-0.42/4.46]? Gaia EDR3 BP-RP color index
99-103 F5.3 mag e_BP-RP [0.005/0.8]? rms uncertainty on BP-RP
105-112 F8.3 mas/yr pmRA [-76.1/105]? Gaia EDR3 proper motion component;
pmRA*cosDE
114-118 F5.3 mas/yr e_pmRA [0.01/3]? rms uncertainty on pmRA
120-127 F8.3 mas/yr pmDE [-58.6/109]? Gaia EDR3 proper motion component
129-133 F5.3 mas/yr e_pmDE [0.01/2]? rms uncertainty on pmDE
135-141 F7.3 mas plx [-7.95/16.5]? Gaia EDR3 trigonometric parallax
143-147 F5.3 mas e_plx [0.009/2]? rms uncertainty on plx
149-152 F4.2 --- Pmemb [0/1]? Membership probability
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 04-May-2022