J/AJ/117/17 Hubble Deep Field near-IR obs. (Thompson+, 1999)
Near-infrared camera and multi-object spectrometer observations of the
Hubble Deep Field: observations, data reduction, and galaxy photometry.
Thompson R.I., Storrie-Lombardi L.J., Weymann R.J., Rieke M.J.,
Schneider G., Stobie E., Lytle D.
<Astron. J. 117, 17 (1999)>
=1999AJ....117...17T 1999AJ....117...17T
ADC_Keywords: Galaxies, photometry ; Photometry, infrared
Mission_Name: HST
Keywords: cosmology: observations - galaxies: fundamental parameters
Abstract:
This paper presents data obtained during the NICMOS Guaranteed Time
Observations of a portion of the Hubble Deep Field. The data are in a
catalog format similar to the publication of the original WFPC2 Hubble
Deep Field program (Williams et al., 1996, Cat. J/AJ/112/1335). The
catalog contains 342 objects in a 49.1"x48.4" subfield of the total
observed field, 235 of which are considered coincident with objects in
the WFPC2 catalog. The 3σ signal-to-noise ratio level is at an
aperture AB magnitude of approximately 28.8 at 1.6µm. The catalog
sources, listed in order of right ascension, are selected to satisfy a
limiting signal-to-noise ratio criterion of greater than or equal to
2.5. This introduces a few false detections into the catalog, and
users should take careful note of the completeness and reliability
levels for the catalog discussed in sections 9 and 10. The catalog
also contains a test parameter indicating the results of half-catalog
tests and the degree of coincidence with the original WFPC2 catalog.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table4.dat 125 342 Catalogue of detected sources
table6.dat 125 205 Catalog of detected sources with signal-to-noise
ratio levels less than 2.5
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See also:
J/AJ/112/1335 : Hubble Deep Field observations (Williams+ 1996)
Byte-by-byte Description of file: table4.dat table6.dat
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Bytes Format Units Label Explanations
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1- 7 F7.3 --- [TSW99] ID Running number for each object (1)
9- 17 A9 --- WFPC Nearest WFPC2 source from the Williams et al.
(1996, Cat. J/AJ/112/1335) catalog (2)
19- 22 F4.2 arcsec Sep Separation between the NICMOS and the nearest
WFPC2 object (WFPC) (3)
24- 30 F7.3 pix Xpos X position (4)
32- 37 F6.2 pix Ypos Y position (4)
39- 40 I2 h RAh Source centroid right ascension (J2000) (5)
42- 43 I2 min RAm Source centroid right ascension (J2000)
45- 49 F5.2 s RAs Source centroid right ascension (J2000)
51 A1 --- DE- Source centroid declination sign (J2000)
52- 53 I2 deg DEd 62 Source centroid declination (J2000)
55- 56 I2 arcmin DEm Source centroid declination (J2000)
58- 63 F6.3 arcsec DEs Source centroid declination (J2000)
65- 69 F5.2 mag t160 ?=99.99 F160W image total magnitude (6)
71- 75 F5.2 mag i160 ?=99.99 F160W image isophotal magnitude (6)
77- 81 F5.2 mag a160 ?=99.99 F160W image aperture magnitude (6)
83- 87 F5.2 mag t110 ?=99.99 F110W image total magnitude (6)
89- 93 F5.2 mag i110 ?=99.99 F110W image isophotal magnitude (6)
95- 99 F5.2 mag a110 ?=99.99 F110W image total magnitude (6)
101-107 F7.3 --- S/N Signal-to-noise ratio value (7)
108-113 F6.3 arcsec+2 Area Isophotal area of the source as determined
from the value returned by KFOCAS.
115-119 F5.3 arcsec r1 Half-light radius returned by KFOCAS
121-125 I5 --- Tests Reliability test parameter (8)
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Note (1): The numbers after the decimal point indicate the level of splitting by
KFOCAS up to three levels of daughter objects. Since the list is
arranged by right ascension, daughter objects can appear separately
from the parent objects. No object is repeated. Numbers of 900 or
higher are split F110W objects that are not coincident with any
F160W split even though some of the components are in common.
Sources with signal-to-noise ratio levels less than 2.5 have ID
numbers of 500 or greater.
Note (2): This is not necessarily the same object, just the nearest.
Note (3): A large value of separation indicates that the NICMOS and WFPC2 object
are probably not associated.
Note (4): x- and y-values of the centroid of the source in the F160W or F110W
image. If the object is detected in both images, the x- and y-values
refer to the F160W image. Objects detected only by SExtractor have the
values determined by SExtractor. This order of precedence holds for
all of the subsequent values.
Note (5): The source positions assume that the central star, NICMOS 145, and the
WFPC2 object 4-454 have the same position and that the measured plate
scales of the NICMOS Camera 3 are correct. In this sense all
positions are relative to the position of the WFPC2 4-454 object.
Note (6): The aperture diameter for the aperture magnitudes is 0.6". The total
and isophotal magnitudes are as described in Williams et al. (1996,
Cat. J/AJ/112/1335).
A value of 99.99 indicates that the object was not detected in that
filter.
The F160W and F110W objects are considered to be in common if they
lie within 0.25" of each other. If the last digit in the test
parameter (see below) is 3, the magnitudes are from the SExtractor
procedure.
Note (7): S/N quoted in the catalog is calculated by the same technique used in
the optical HDF.
Note (8): This parameter indicates which of the various reliability tests the
source passed. A source that passed all tests has a value of 22111,
one that passed no tests has a value of 00000. The first number is
0, 1, or 2 if the source was detected in none, one, or both of the
F160W half-catalogs. For an explanation of the half-catalogs see
section 10.1. The second number is the same test in the F110W
catalog. The third number is 0 or 1 depending on whether the source
was found in both NICMOS bands of the full image extractions. The
fourth number is 0 or 1 depending on whether the source is detected
in the WFPC2 catalog. The last number is 0 or 1 depending on whether
the source was found in the independent Sextractor catalog. Note the
discussions in sections 10.2 and 10.3 on the differences in
half-catalog detection probabilities between KFOCAS and SExtractor.
In all cases a common detection means that the source centroids lie
within 0.25" of each other. No color or magnitude tests are applied
as part of the common object association.
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History: From AJ electronic version
(End) James Marcout, Patricia Bauer [CDS] 26-Feb-1999