II/208 BVRI CCD photometry in the field of M 31 (Magnier+ 1992)
BVRI CCD photometry of 361281 objects in the field of M 31
Magnier E.A., Lewin W.H.G., van Paradijs J., Hasinger G.,
Jain A., Pietsch W., Truemper J.
<Astron. Astrophys. Suppl. Ser. 96, 379 (1992)>
=1992A&AS...96..379M 1992A&AS...96..379M
Astrometry in the field of M 31.
Magnier E.A., Lewin W.H.G., van Paradijs J., Hasinger G.,
Pietsch W., Truemper J.
<Astron. Astrophys., 272, 695 (1993)>
=1993A&A...272..695M 1993A&A...272..695M
Extension of the Magnier et al. catalogue of objects in the field of M31.
Haiman Z., Magnier E., Lewin W.H.G., Lester R.R., van Paradijs J.,
Hasinger G., Pietsch W., Supper R., Truemper J.
<Astron. Astrophys., 286, 725 (1994)>
=1994A&A...286..725H 1994A&A...286..725H
ADC_Keywords: Photometry, CCD ; Regional catalog ; Stars, faint ;
Keywords: Galaxies: M31 - photometry - spiral - stellar content
Description:
Deep BVRI CCD photometry was performed on a 1 square degree region of
M31. The observations were made between September 12 and September 27,
1990, using the McGraw-Hill 1.3m telescope at the
Michigan-Dartmouth-MIT (MDM) observatory at Kitt Peak.
The catalogue has typical completion limits of 22.3Bmag, 22.2Vmag,
22.2Rmag and 20.9Imag. Photometric accuracy is about 2% at Vmag=19.
The final astrometric calibrations take into account the systematic
error discovered in the Berkhuijsen etal (1987) catalog (Magnier etal
1993). They are in the J2000 system and are eventually tied to the HST
Guide Star Catalog. The final photometric calibrations are tied via
the NGC 206 region to photometry taken at the Michigan-Dartmouth-MIT
(MDM) 1.3m in September and October 1993. These are tied to the
Landolt (1992) system of standard stars, and are in the
Johnson-Kron-Cousins system (BVRcIc).
Caveats:
There are several known problems with the catalog. First, there are
likely to be some repeated detections of certain sources (i.e.,
multiple entries for the same object). Second, the wings of bright
sources in some cases may be included as distinct sources. Third, the
completeness limits are a strong function of position, and a much
lower near the core and the core of M32. Fourth, variable stars,
blended star, and stars with cosmic ray hits, cosmetic problems or
other failures may have highly abnormal colors and magnitudes. In
general, we expect these problems to be small, but the user is
cautioned to watch for these possible problems.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
bv.dat 143 47776 Stars with both B and V photometry
bvi.dat 143 30177 Stars with all B, V and I photometry
catalog.dat 143 485388 The catalogue of M31 stars.
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Byte-by-byte Description of file: *.dat
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Bytes Format Units Label Explanations
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2- 7 I6 --- Seq [1,485425]+ Sequence number
9- 17 F9.6 deg RAdeg Right ascension (J2000)
19- 27 F9.6 deg e_RAdeg Scatter for the star, if multiple measurements
29- 37 F9.6 deg DEdeg Declination (J2000)
39- 47 F9.6 deg e_DEdeg Scatter if multiple measurements
49- 55 F7.3 mag Bmag ?=-9.999 B magnitude
57- 61 F5.3 mag e_Bmag ?=0.000 Mean error on Bmag
63- 64 I2 --- o_Bmag [-5,7] Number of detection in B images (2)
66- 71 A6 --- tBmag [0-57] DoPHOT type for each detection (1)
73- 79 F7.3 mag Vmag ?=-9.999 V magnitude
81- 85 F5.3 mag e_Vmag ?=0.000 Mean error on Vmag
87- 88 I2 --- o_Vmag [-6,7] Number of detection in V images (2)
90- 95 A6 --- tVmag [0-57] DoPHOT type for each detection (1)
97-103 F7.3 mag Rmag ?=-9.999 R magnitude (Cousins)
105-109 F5.3 mag e_Rmag ?=0.000 Mean error on Rmag
111-112 I2 --- o_Rmag [-5,6] Number of detection in R images (2)
114-119 A6 --- tRmag [0-57] DoPHOT type for each detection (1)
121-127 F7.3 mag Imag ?=-9.999 I magnitude (Cousins)
129-133 F5.3 mag e_Imag ?=0.000 Mean error on Imag
135-136 I2 --- o_Imag [-5,6] Number of detection in I images (2)
138-143 A6 --- tImag [0-57] DoPHOT type for each detection (1)
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Note (1): See Schechter et al. (1993) for a description of DoPHOT;
the "DoPHOT types" assign numbers depending of the similarity
of the objects profile to the PSF. The definitions are:
1 = star
2 = extended profile (ie, galaxy)
3 = double profile (pair of stars)
4 = failed to converge in 4 parameter fit
5 = large number of bad pixels (ie, near the edge of CCD)
7 = failed to converge in 7 parameter fit.
Note (2): negative numbers indicate that the object lies in a crowded
area, and is likely to be either a blended image of two stars,
or may be mismatched in the other filters.
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Acknowledgements:
It is a pleasure to thank Eugene Magnier
for providing the catalogue.
References:
Berkhuijsen E.M., Humphreys R.M., Ghigo F.D., Zumach W.
=1988A&AS...76...65B 1988A&AS...76...65B, Cats. II/144 and II/145
Haiman Z., Magnier E.A., Lewin W.H.G., Lester R.R., van Paradijs J.,
Hasinger G., Pietsch W., Supper R., Truemper J.
=1994A&A...286..725H 1994A&A...286..725H
Landolt A.U. =1992AJ....104..340L 1992AJ....104..340L, =Cat. II/183
Magnier E.A., Lewin W.H.G., van Paradijs J., Hasinger G., Jain A.,
Pietsch W., Truemper J. =1992A&AS...96..379M 1992A&AS...96..379M
Magnier E.A., Lewin W.H.G., van Paradijs J., Hasinger G., Pietsch W.,
Truemper J. =1993A&A...272..695M 1993A&A...272..695M
Schechter P.L., Mateo M., Saha A., =1993PASP..105..134S 1993PASP..105..134S
(End) Francois Ochsenbein [CDS] 06-Sep-1996