J/A+A/409/361 Extension of ICRF for selected areas down to V=16 (Camargo+, 2003)
Extension of the ICRF for selected areas down to the 16th magnitude - II.
Camargo J.I.B., Ducourant C., Teixeira R., Le Campion J.-F., Rapaport M.,
Benevides-Soares P.
<Astron. Astrophys. 409, 361 (2003)>
=2003A&A...409..361C 2003A&A...409..361C
ADC_Keywords: Positional data ; Proper motions ; Photometry
Keywords: astrometry - reference systems
Description:
A catalogue of accurate positions and proper motions for 678,828
objects is provided. Objects are within areas of special astronomical
interest, containing extragalactic radio sources, mostly from ICRF
(see Cat. I/251), and pre-main-sequence (PMS) stars in Southern
star-forming regions (Chamaeleon, Lupus and Upper Scorpius-Ophiuchus).
This work represents a major upgrade of that presented in Camargo et
al., 2001, Cat. J/A+A/375/308, aiming at the extension of the ICRF
at optical wavelengths in regions of special astronomical interest,
using observations from the Bordeaux and Valinhos meridian circles.
Along with the new fields, the main differences, when compared to the
first release, are: a much larger sky coverage, the replacement of the
AC2000 by its upgraded version AC2000.2 (I/275) as one of the first
epoch astrometrical sources, inclusion of Tycho-2 (I/259) and 2MASS
(2nd Incremental Data Release, See Cat II/246) photometry when
available, and the correction for a magnitude equation on the Valinhos
right ascension system as well. Positional external precisions, on
both coordinates, range from 50-60mas (V≤13.5) to 70-140mas
(13.5<V≤16.0). For the proper motions, precisions range from
3mas/year to about 15mas/year, depending on magnitude and declination.
The strips scanned by the meridian circles are described in Table 1
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
catalog.dat 172 546459 Bordeaux and Valinhos meridian circle catalogue
table1.dat 81 242 Approximate central coordinates of the meridian
strips
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See also:
J/A+A/375/308 : Extension of ICRF for selected areas for V≤15 (Camargo+ 2001)
I/251 : VLBI International Celestial Reference Frame (ICRF) (Ma+, 1997)
I/239 : The Hipparcos and Tycho Catalogues (ESA 1997)
I/259 : The Tycho-2 Catalogue (Hog+ 2000)
I/275 : The AC 2000.2 Catalogue (Urban+ 2001)
I/252 : The USNO-A2.0 Catalogue (Monet+ 1998)
I/146 : Positions and Proper Motions - North (Roeser+, 1988)
I/193 : Positions and Proper Motions - South (Bastian+ 1993)
I/265 : Second Cape Photographic Catalogue (CPC2) (Zacharias+, 1999)
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
http://ad.usno.navy.mil/tac/ : Twin Astrographic Catalog Version 2 Home Page
Byte-by-byte Description of file: catalog.dat
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Bytes Format Units Label Explanations
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1- 2 I2 h RAh Right Ascension (hours) ICRS, epoch EpRA-1900
4- 5 I2 min RAm Right Ascension (minutes) ICRS
7- 12 F6.3 s RAs Right Ascension (seconds) ICRS
14 A1 --- DE- Declination (sign) ICRS, epoch EpDE-1900
15- 16 I2 deg DEd Declination (degrees) ICRS, epoch EpDE-1900
18- 19 I2 arcmin DEm Declination (minutes) ICRS
21- 25 F5.2 arcsec DEs Declination (seconds) ICRS
27- 30 I4 mas/yr pmRA Proper motion mu_alpha*cos(dec) ICRS
32- 35 I4 mas/yr pmDE Proper motion mu_delta ICRS
38- 42 F5.2 mag VmagC V magnitude as obtained from BMC (Bordeaux)
or VMC (Valinhos)
45- 51 F7.3 mag BTmag ? B magnitude as obtained from the Tycho-2
52- 58 F7.3 mag VTmag ? V magnitude as obtained from the Tycho-2
60- 66 F7.3 mag Jmag ?=-99.999 J magnitude from the 2MASS (1)
68- 74 F7.3 mag Hmag ?=-99.999 H magnitude from the 2MASS (1)
76- 82 F7.3 mag Kmag ?=-99.999 K magnitude from the 2MASS (1)
87- 92 F6.3 yr EpRA-1900 RA epoch minus 1900
96-101 F6.3 yr EpDE-1900 DE epoch minus 1900
104-110 F7.3 yr DT Largest time interval for proper motion
determination
114-115 I2 mas e_RAs Standard error in RA*cos(dec) for EpRA
118-119 I2 mas e_DEs Standard error in DE for EpDE
121-122 I2 mas/yr e_pmRA Standard error in pmRA
124-125 I2 mas/yr e_pmDE Standard error in pmDE
130-131 I2 --- Nobs Number of meridian observations
134-139 I6 --- HIP ? HIPPARCOS (Cat. I/239) Catalogue number
141-152 A12 --- TYC ? Tycho-2 number (see Note (1) in I/259)
153 A1 --- f_TYC [*] Presence in Tycho-1 catalogue (2)
158-164 I7 --- AC2000.2 ? AC2000.2 (Cat. I/275) number
166 A1 --- C1 [BV] Current epoch catalogue:
[B]ordeaux or [V]alinhos (3)
167 A1 --- C2 [A] A: use of AC2000.2 data, Cat. I/275
168 A1 --- C3 [U] U: use of USNO-A2.0 data, Cat. I/252
169 A1 --- C4 [P] P: use of PPM data,
PPM North I/146, PPN South I/1993
170 A1 --- C5 [T] T: use of TAC-2 data, Zacharias &
Zacharias, 1999AJ....118.2503Z 1999AJ....118.2503Z
171 A1 --- C6 [C] C: use of CPC-2 data, Cat. I/265
172 A1 --- C7 [E] ESO plate measurements (4)
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Note (1): 2MASS 2nd Incremental Data Release
Note (2): Presence in Tycho-1 catalogue:
'*' = Object not present in Tycho-1 catalogue (Cat. I/239)
' ' = Object present in Tycho-1 catalogue
Note (3): Example:
The character sequence "V U E" indicates that proper motion and mean
position for a given star was obtained from the Valinhos meridian
circle, USNO-A2.0 and ESO plates
Note (4): Measured with the MAMA measuring machine
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Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1 A1 --- Zone [VB] V: Valinhos zones, B: Bordeaux zones
3- 23 A21 --- TARG ICRF name or other identifier of the target object
28- 32 I5 --- Nobj Total number of selected objects in the region: 3 or
more observations in each coordinate with
σRA*cos(DE) and σDE≤250mas
36- 38 I3 mas DaCd Mean, in units of milliarcseconds in RA*cos(DE),
for the positional precision in RA of the objects
computed in the column (Nobj)
40- 42 I3 mas Dd Mean, in units of milliarcseconds, for the
positional precision in DE for the objects computed
in the column (Nobj)
46- 47 I2 h RAh Approximate strip central right ascension (J2000) (5)
49- 50 I2 min RAm Approximate strip central right ascension (J2000) (5)
52- 55 F4.1 s RAs Approximate strip central right ascension (J2000) (5)
57 A1 --- DE- Approximate strip central declination (J2000) (5)
58- 59 I2 deg DEd Approximate strip central declination (J2000) (5)
61- 62 I2 arcmin DEm Approximate strip central declination (J2000) (5)
64- 65 I2 arcsec DEs Approximate strip central declination (J2000) (5)
72- 75 F4.1 mag Vmag ? V magnitude as given in the ICRF (Cat. I/251)
79- 80 I2 --- Nobs ? Number of observations of the target region
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Note (5): Zones dimensions are typically 28' in declination and 80min in
right ascension to the Bordeaux meridian circle strips and 13' in
declination and 40min in right ascension to the Valinhos meridian
circle strips.
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Acknowledgements: Julio Camargo
(End) Patricia Bauer [CDS] 13-Oct-2003