J/A+A/445/493 UBV(RI)c photometry of NGC 2425 and NGC 2635 (Moitinho+, 2006)
Open clusters in the Third Galactic Quadrant.
II. The intermediate age open clusters NGC 2425 and NGC 2635.
Moitinho A., Carraro G., Baume G., Vazquez R.A.
<Astron. Astrophys. 445, 493 (2006)>
=2006A&A...445..493M 2006A&A...445..493M
ADC_Keywords: Clusters, open ; Photometry, UBVRI ; Photometry, CCD
Keywords: Galaxy: open clusters and associations: individual: NGC 2425, NGC 2635
Abstract:
We analyse CCD broad band (UBV(RI)c) photometric data obtained in the
fields of the poorly studied open clusters NGC 2425 and NGC 2635. Both
clusters are found to be of intermediate age thus increasing the
population of open clusters known to be of the age of, or older than,
the Hyades. More explicitly, we find that NGC 2425 is a 2.2Gyr old
cluster, probably of solar metallicity, located at 3.5kpc from the
Sun. NGC 2635 is a Hyades age (600Myr) cluster located at a distance
of 4.0kpc from the Sun. Its Colour Magnitude Diagram reveals that it
is extremely metal poor for its age and position, thus making it a
very interesting object in the context of Galactic Disk chemical
evolution models.
Description:
The data come from CCD photometric observations carried out at two
different telescopes:
- The Cerro Tololo Inter-American Observatory (CTIO): UBV(RI)c CCD
photometric data of the field of NGC 2425 and 2635 were acquired
with the 0.9m telescope on the nights of January 4, 6 and 7, 1998.
- The European Southern Observatory (ESO): CCD VI observations of the
fields of NGC 2425 using the new EMMI read arm camera at the NTT
on the photometric night of December 9, 2002.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 106 3304 Photometric catalogue of the NGC 2425 region
table3.dat 115 3113 Photometric catalogue of the NGC 2635 region
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See also:
J/A+A/417/961 : UBV(RI)c photometry of NGC 2580 and NGC 2588 (Baume+, 2004)
Byte-by-byte Description of file: table2.dat table3.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- Seq Sequential number (this work) in the region
6- 11 F6.1 pix Xpos X position in CCD pixels
13- 18 F6.1 pix Ypos Y position in CCD pixels
20- 21 I2 h RAh Right Ascension (J2000)
23- 24 I2 min RAm Right Ascension (J2000)
26- 29 F4.1 s RAs Right Ascension (J2000)
31 A1 --- DE- Declination sign (J2000)
32- 33 I2 deg DEd Declination (J2000)
35- 36 I2 arcmin DEm Declination (J2000)
38- 41 F4.1 arcsec DEs Declination (J2000)
43- 48 F6.3 mag Umag ? U magnitude
50- 54 F5.3 mag e_Umag ? Error in Umag
56- 61 F6.3 mag Bmag ? B magnitude
63- 67 F5.3 mag e_Bmag ? Error in Bmag
69- 74 F6.3 mag Vmag V magnitude
76- 80 F5.3 mag e_Vmag Error in Vmag
82- 87 F6.3 mag Rcmag ? Cousins R magnitude
89- 93 F5.3 mag e_Rcmag ? Error in Rcmag
95-100 F6.3 mag Icmag ? Cousins I magnitude
102-106 F5.3 mag e_Icmag ? Error in Icmag
114-115 A2 --- Memb ? Membership assignment, only table3 (1)
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Note (1): Membership assignment as follows:
lm = likely member
pm = probable member
nm = non-member
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Acknowledgements: Andre Moitinho, andre(at)astro.oal.ul.pt
References:
Moitinho, Paper I 2001A&A...370..436M 2001A&A...370..436M
(End) Patricia Vannier [CDS] 08-Sep-2005