ADC/CDS Standard Document for Catalog:/external/photom/E2006/
ADC/CDS Standard Document for Catalog:
E/II/6 The DENIS database (Epchtein+, 1999)
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A preliminary database of DENIS (DEep Near-Infrared Survey) point sources.
Epchtein N., Deul E., Derriere S., Borsenberger J., Egret D., Simon G.,
Alard C., Balazs L.G., De Batz B., Cioni M.-R., Copet E., Dennefeld M.,
Forveille T., Fouque P., Garzon F., Habing H.J., Holl A., Hron J.,
Kimeswenger S., Lacombe F., Le Bertre T., Loup C., Mamon G.A., Omont A.,
Paturel G., Persi P., Robin A.C., Rouan D., Tiphene D., Vauglin I.,
Wagner S.J.
<Astron. Astrophys. 349, 236 (1999)>
=1999A&A...349..236E (SIMBAD/NED BibCode)
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ADC_Keywords: Infrared sources ; Photometry, infrared ; Surveys ;
External catalog
Mission_Name: DENIS
Keywords: infrared: stars - Galaxy: stellar content -
stars: low-mass, brown dwarfs -
astronomical data bases: miscellaneous - surveys
Location: http://cdsweb.u-strasbg.fr/denis.html
Abstract:
This paper announces the release at CDS of a substantial set of point
sources detected by the DENIS project. DENIS is the first astronomical
survey of the Southern sky in two near-infrared bands (J at 1.25{mu}m,
and K_s_ at 2.15{mu}m) and one optical band (Gunn-i at 0.82{mu}m),
conducted by a European consortium, using the 1m telescope at ESO, La
Silla (Chile). The first data release, described here, consists of a
preliminary set of about 17 million extracted point sources,
corresponding to 102 strips (2% of the Southern sky), and resulting
from observations performed in 1996.
Description:
DENIS is a project to survey the all-southern sky in three wavelength
bands (Gunn-i 0.82 {mu}m; J, 1.25 {mu}m; and K_s, 2.15 {mu}m) with
limiting magnitudes 18.5, 16.5 and 14.0, respectively. The observations
are performed with the 1m-ESO telescope at La Silla (Chile).
The DENIS instrument is made up of a 3-channel camera built of
commercially available detector arrays by the Observatoire de Paris
and with major contributions from other European Institutes, notably:
the IAS in Frascati, the Observatoire de Grenoble, the University of
Innsbruck, the Observatoire de Lyon, and the IAC in Tenerife. The
survey is carried out by observing strips of 30 {deg} in declination
and 12 arcminutes in Right Ascension with an overlap of 2 arcminutes
between consecutive strips. The survey started at the end of 1995 and
is expected to be completed in 2000. The data are reduced in two
consecutive steps, the first at the Institut d'Astrophysique de Paris
and the second at the Leiden Observatory. The position of a general
extracted point source is provided with an accuracy better than 1
arcsec and its magnitude to better than 0.1 mag. The data will be made
publicly available as soon as possible after completing the data
reduction. The Centre de Donnees Astronomiques de Strasbourg (CDS) is
implementing the final databases and is providing access of the
processed and calibrated data to the worldwide community.
The principal investigator of the DENIS project is N. Epchtein
(Observatoire de la Cote d'Azur); scientists and engineers from
seven European countries and from Brazil are involved.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . The present file
denis.sam 354 100 Sample of DENIS output (around NGC 4038)
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See also:
http://cdsweb.u-strasbg.fr/denis.html : DENIS documentation
J/A+AS/135/133 : First DENIS I-band extragalactic catalog (Vauglin+ 1999)
Nomenclature Notes:
The recommended way to designate the DENIS sources is JHHMMSS.s-DDMMSS
Byte-by-byte Description of output: denis.sam
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Bytes Format Units Label Explanations
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1- 16 A16 --- Name DENIS identifier: JHHMMSS.s-DDMMSS
18- 21 I4 --- Strip DENIS strip number
23- 29 I7 --- SeqNr Object sequence number (from make_ssc)
31- 40 F10.6 deg RAdeg Right ascension (J2000)
42- 51 F10.6 deg DEdeg Declination (J2000)
53- 60 F8.6 deg ErrPos Random Position Error
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62- 67 F6.3 mag Ap7mag_I ?Magnitude from FLUX_APER 7''
69- 74 F6.3 mag e_Ap7mag_I ?Magnitude error from FLUXERR_APER 7''
76- 81 F6.3 mag Ap15mag_I ?Magnitude from FLUX_APER 15''
83- 88 F6.3 mag e_Ap15mag_I ?Magnitude error from FLUXERR_APER 15''
90- 95 F6.3 mag Automag_I ?Magnitude from FLUX_AUTO
97-102 F6.3 mag e_Automag_I ?Magnitude error from FLUXERR_AUTO
104-111 F8.6 deg MajAxis_I ?Major axis object ellipse
113-120 F8.6 deg MinAxis_I ?Minor axis object ellipse
122-129 F8.6 --- ell_I [0,1]? Ellipticity of object (1)
131-136 F6.2 deg Theta_I [-90,+90]? Position angle of ellipse (2)
138-141 F4.2 --- Stellar_I [0,1]? "Stellarity" of object (3)
143-145 I3 --- Extr_I ?Extraction flags (4)
147-148 I2 --- Ima_I ?Image flags (5)
150-150 I1 --- Arti_I ?Image Artifact marker (6)
152-154 I3 --- Merged_I [0,127]? Merged objects indicator (7)
156-158 I3 --- Field_I ?Field position reference (8)
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160-165 F6.3 mag Ap7mag_J ?Magnitude from FLUX_APER 7''
167-172 F6.3 mag e_Ap7mag_J ?Magnitude error from FLUXERR_APER 7''
174-179 F6.3 mag Ap15mag_J ?Magnitude from FLUX_APER 15''
181-186 F6.3 mag e_Ap15mag_J ?Magnitude error from FLUXERR_APER 15''
188-193 F6.3 mag Automag_J ?Magnitude from FLUX_AUTO
195-200 F6.3 mag e_Automag_J ?Magnitude error from FLUXERR_AUTO
202-209 F8.6 deg MajAxis_J ?Major axis object ellipse
211-218 F8.6 deg MinAxis_J ?Minor axis object ellipse
220-227 F8.6 --- ell_J [0,1]? Ellipticity of object (1)
229-234 F6.2 deg Theta_J [-90,+90]? Position angle of ellipse (2)
236-239 F4.2 --- Stellar_J [0,1]? "Stellarity" of object (3)
241-243 I3 --- Extr_J ?Extraction flags (4)
245-246 I2 --- Ima_J ?Image flags (5)
248-248 I1 --- Arti_J ?Image Artifact marker (6)
250-252 I3 --- Merged_J [0,127]? Merged objects indicator (7)
254-256 I3 --- Field_J ?Field position reference (8)
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258-263 F6.3 mag Ap7mag_K ?Magnitude from FLUX_APER 7''
265-270 F6.3 mag e_Ap7mag_K ?Magnitude error from FLUXERR_APER 7''
272-277 F6.3 mag Ap15mag_K ?Magnitude from FLUX_APER 15''
279-284 F6.3 mag e_Ap15mag_K ?Magnitude error from FLUXERR_APER 15''
286-291 F6.3 mag Automag_K ?Magnitude from FLUX_AUTO
293-298 F6.3 mag e_Automag_K ?Magnitude error from FLUXERR_AUTO
300-307 F8.6 deg MajAxis_K ?Major axis object ellipse
309-316 F8.6 deg MinAxis_K ?Minor axis object ellipse
318-325 F8.6 --- ell_K [0,1]? Ellipticity of object (1)
327-332 F6.2 deg Theta_K [-90,+90]? Position angle of ellipse (2)
334-337 F4.2 --- Stellar_K [0,1]? "Stellarity" of object (3)
339-341 I3 --- Extr_K ?Extraction flags (4)
343-344 I2 --- Ima_K ?Image flags (5)nomenclature
346-346 I1 --- Arti_K ?Image Artifact marker (6)
348-350 I3 --- Merged_K [0,127]? Merged objects indicator (7)
352-354 I3 --- Field_K ?Field position reference (8)
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Note (1): the ellipticity is defined by:
e = (sqrt(a^2^-b^2^))/a
i.e. a value of zero means a circle,
a value close to one corresponds to a line.
Note (2): the angle theta is zero in the East and rotates anti-clockwise;
the "classical" position angle PA is therefore (90{deg}-theta)
Note (3): a value of 1 identifies the object as a star,
and a value 0f 0 indicates a galaxy.
Note (4): the extraction flag, defined by SExtractor:
1: the object has neighbours, bright and close enough to
significantly bias the MAG_AUTO photometry, or bad pixels;
2: the object was originally blended with another one;
4: at least one pixel of the object is saturated (or very close to);
8: the object is truncated (too close to an image boundary);
16: object's aperture data are incomplete or corrupted;
32: object's isophotal data are incomplete or corrupted;
64: a memory overflow occurred during deblending;
128: a memory overflow occurred during extraction.
Note (5): the image flag is defined according to the flag.fits file.
1: regression failed for this pixel;
2: flat derived is less than 0.01;
3: abnormally high flat;
4: abnormally high residual after adjustment;
5: bias away from mean by more than 5 sigmas;
9: insufficient pixels left after iterative clipping.
Caution: different values of these flags may occur in one stellar
image. Because these flags do not have binary exclusive values the
ORing of these flags causes loss of information! This ORing takes
place both inside an isophotal area and for merging of multiple
detections of the same source.
Note (6): the Artifact flag: it identifies detector/instrument specific
conditions. The flag can assume the following values:
1: Glitch;
2: Optical Ghost;
4: Saturation in I.
Note (7): the Merged objects indicator takes the values:
0 = no detection, 1 = good detection, 2(+?) = object merge
Note (8): the Field position reference refers back to the frame sequence
number (2MUFIELD) of the frame from which the particular source
was extracted. In case of a merge, one of the frame numbers in
the merge is given.
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Acknowledgements:
DENIS is the result of a joint effort involving human and financial
contributions of several Institutes mostly located in Europe. It has
been supported financially mainly by the French Institut National des
Sciences de l'Univers, CNRS, and French Education Ministry, the
European Southern Observatory, the State of Baden-Wuerttemberg, and
the European Commission under a network of the Human Capital and
Mobility program.
References:
The DENIS Consortium (December 1998)
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(End) Sebastien Derriere, Francois Ochsenbein [CDS] 06-Sep-1999