J/A+A/521/A39 Cordoba Carte du Ciel-Astrographic Catalog, CCAC (Orellana+, 2010)
A revisit to the region of Collinder 132 using CdC and AC plates.
Orellana R.B., De Biasi M.S., Bustos Fierro I.H., Calderon J.H.
<Astron. Astrophys. 521, A39 (2010)>
=2010A&A...521A..39O 2010A&A...521A..39O
ADC_Keywords: Clusters, open ; Proper motions
Keywords: open cluster and associations: general -
open cluster and associations: individual: Cr132 - astrometry
Abstract:
Based on stellar positions and proper motions, we aim to re-analyse
the region of the controversial open cluster Collinder 132. Methods.
We have developed a model which analyse the proper motion distribution
and the stellar density to find moving groups. The astrometric data
was obtained from four Carte du Ciel (CdC) and one Astrogaphic
Catalogue (AC) plates of the Cordoba Astronomical Observatory
collection (Argentina).
We detected an open cluster from the field stars and calculated the
mean proper motion and the membership probabilities of the stars of
the region. We report new coordinates of its centre RAc=108.347deg,
DEc=-31.011deg, the components of mean proper motion
muRAcosDE=-2.62±0.44mas/yr, muDE=4.79±0.88mas/yr. 11 stars are
astrometric members giving a value of 370 for the cluster angular
diameter. 6 stars fullfill astrometric and photometric analysis for
being cluster members and locate the cluster at 360pc from the Sun. An
over-density in the VPD was found after removing the cluster members,
consequently a simple model for the proper motion distribution of an
association and of the field was adopted.
We report the components of the association mean proper motion
muRAcosDE=-1.38±0.14mas/yr, muDE=2.26±0.16mas/yr. 174
astrometric members were found while 11 members have been located
between 417 and 660pc from the Sun by Tycho-2 photometry.
Description:
This is Cordoba Carte du Ciel-Astrographic Catalog (CCAC) constructed
from four Carte du Ciel and one Astrographic Catalog photographic
plates for first epoch positions in the region of the open cluster
Collinder 132. The plates were digitized using the MAMA measuring
machine from the Paris Observatory. Stars from Tycho-2 catalogue (Hog
et al., 2000, Cat. I/259) were used as reference stars. Every plate
was reduced independently from the others adopting a first order
polynomial in the measured coordinates. Proper motions were calculated
using the CCAC positions as first epoch, and as second epoch the
positions given by UCAC2 (Zacharias et al., 2004, Cat. I/289) and
USNO-B1.0 (Monet et al., 2003, Cat. I/284).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
ccac.dat 132 9055 Stellar positions and proper motions of all stars
table6.dat 89 149 Astrometric members of Collinder 132 association
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See also:
I/259 : The Tycho-2 Catalogue (Hog+ 2000)
I/284 : The USNO-B1.0 Catalog (Monet+ 2003)
I/289 : The UCAC2 Catalogue (Zacharias+ 2003)
Byte-by-byte Description of file: ccac.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- CCAC Star number in CCAC
7- 17 F11.7 deg RAdeg Right ascension at Epoch EpRA (ICRS)
20- 30 F11.7 deg DEdeg Declination at Epoch EpDE (ICRS)
33- 36 F4.2 arcsec e_RAdeg Mean error in right ascension at EpRA
39- 42 F4.2 arcsec e_DEdeg Mean error in declination at EpDE
44 I1 --- Npl Number of plates in the determination of
RA and DE
47- 53 F7.2 yr EpRA Mean epoch of the plates in RA
56- 62 F7.2 yr EpDE Mean epoch of the plates in DE
65 I1 --- Nep Number of epochs in the determination of
proper motion
68- 73 F6.1 mas/yr pmRA ? Proper motion in right ascension
76- 81 F6.1 mas/yr pmDE ? Proper motion in declination
85- 89 F5.1 mas/yr e_pmRA ? Error of proper motion in right ascension
93- 97 F5.1 mas/yr e_pmDE ? Error of proper motion in declination
99-109 A11 --- TYC Tycho-2 identifier (Cat. I/259)
113-120 I8 --- UCAC2 ? UCAC2 identifier (Cat. I/289)
123-132 A10 --- USNOB1 USNOB1.0 identifier (Cat. I/284)
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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- 4 I4 --- CCAC Star number in CCAC
6- 12 F7.4 arcsec r Distance to the association cluster center
14- 24 F11.7 deg RAdeg Right ascension (ICRS)
26- 36 F11.7 deg DEdeg Declination (ICRS)
38- 41 F4.1 mas/yr pmRA ? Proper motion in right ascension, pmRA*cosDE
43- 46 F4.1 mas/yr pmDE ? Proper motion in declination
48- 51 F4.2 --- Pa Probability of appartenance
53- 63 A11 --- TYC Tycho-2 identifier (Cat. I/259)
65- 70 F6.3 mag BTmag ? Tycho-2 BT magnitude
72- 76 F5.3 mag e_BTmag ? rms uncertainty on BTmag
78- 83 F6.3 mag VTmag ? Tycho-2 VT magnitude
85- 89 F5.3 mag e_VTmag ? rms uncertainty on VTmag
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Acknowledgements:
M.S. De Biasi, debiasi(at)fcaglp.unlp.edu.ar,
R.B. Orellana, rorellan(at)fcaglp.unlp.edu.ar
(End) R.B. Orellana [IALP,FCAG, UNLP Argentina], P. Vannier [CDS] 08-Jul-2010