J/AJ/126/539 The Chandra Deep Fields North and South (Alexander+, 2003)
The Chandra Deep Field North Survey. XIII. 2 Ms point-source catalogs.
Alexander D.M., Bauer F.E., Brandt W.N., Schneider D.P., Hornschemeier A.E.,
Vignali C., Barger A.J., Broos P.S., Cowie L.L., Garmire G.P.,
Townsley L.K., Bautz M.W., Chartas G., Sargent W.L.W.
<Astron. J. 126, 539 (2003)>
=2003AJ....126..539A 2003AJ....126..539A
ADC_Keywords: Surveys ; X-ray sources
Mission_Name: Chandra
Keywords: cosmology: observations - diffuse radiation - galaxies: active -
surveys - X-rays
Abstract:
We present point-source catalogs for the ∼2Ms exposure of the Chandra
Deep Field North, currently the deepest X-ray observation of the
universe in the 0.5-8.0keV band. Five hundred and three (503) X-ray
sources are detected over an ∼448arcmin2 area in up to seven X-ray
bands. Twenty (20) of these X-ray sources lie in the central 5.3
arcmin2 Hubble Deep Field North (13600+3800-3000sources/deg2).
The on-axis sensitivity limits are 2.5x10-17ergs/cm2/s
(0.5-2.0keV) and 1.4x10-16ergs/cm2/s (2-8keV). Source positions
are determined using matched-filter and centroiding techniques; the
median positional uncertainty is ∼0.3".
To allow consistent comparisons, the point-source catalogs for the 1Ms
Chandra Deep Field South (CDF-S; see Cat. J/ApJS/139/369) have also
been produced. Three hundred and twenty-six (326) X-ray sources are
included in the main Chandra South catalog, and an additional 42
optically bright X-ray sources are included in a lower significance
Chandra catalog. We find good agreement with the photometry of the
previously published CDF-S catalogs; however, we provide significantly
improved positional accuracy.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
cdfn-jnl.dat 75 20 *Journal of Chandra Deep Field North observations
cdfn.dat 346 503 CDF-N Main Chandra Catalog (Tables 3 of paper)
cdfn-sup.dat 230 79 CDF-N Supplementary Optically Bright Chandra
Catalog (Tables 7 of paper)
cdfs-jnl.dat 75 11 *Journal of Chandra Deep Field South observations
cdfs.dat 346 326 CDF-S Main Chandra Catalog (Tables A2 of paper)
cdfs-sup.dat 230 42 CDF-S Supplementary Optically Bright Chandra
Catalog (Tables A3 of paper)
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Note on cdfn-jnl.dat: Table 1 of paper.
The focal-plane temperature was -110°C during the first
three observations and -120°C during the others.
Note on cdfs-jnl.dat: Table A1 of paper.
The focal-plane temperature was -110°C during the first
two observations and -120°C during the others.
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See also:
B/chandra : The Chandra Archive Log (CXC, 2002)
J/ApJS/139/369 : Chandra Deep Field South. 1 Ms catalog (Giacconi+, 2002)
J/A+A/403/493 : H-band observation of Chandra Deep Field South (Moy+, 2003)
J/A+A/392/741 : Stellar Catalogue in the Chandra DFS (Groenewegen+ 2002)
J/A+A/375/1 : IR observations of CDF + HDF-South (Saracco+, 2001)
J/A+A/377/442 : Chandra Deep Field South: R-band photometry (Wolf+, 2001)
J/A+A/379/740 : ESO Imaging Survey (EIS) for CDFS (Arnouts+, 2001)
J/AJ/122/2810 : Chandra Deep Field North Survey. V. (Brandt+, 2001)
J/ApJ/554/742 : Chandra Deep Survey of the HDF-N (Hornschemeier+, 2001)
J/AJ/126/632 : 2Ms CDFN X-ray sources UBVRIz'HK' photometry (Barger+, 2003)
Byte-by-byte Description of file: cdfn-jnl.dat cdfs-jnl.dat
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Bytes Format Units Label Explanations
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1- 6 A6 --- ObsID Observation identification number
8- 11 I4 yr Obs.Y Date of the beginning of observation
12 A1 --- --- [/]
13- 14 I2 --- Obs.M Date of the beginning of observation
15 A1 --- --- [/]
16- 17 I2 d Obs.D Date of the beginning of observation
19- 20 I2 h Obs.h Time of the beginning of observation (UT)
22- 23 I2 min Obs.m Time of the beginning of observation (UT)
25- 29 F5.1 ks ExpTime Exposition time (1)
31- 32 I2 h RAh Aim point right ascension (J2000.0) (2)
34- 35 I2 min RAm Aim point right ascension (J2000.0) (2)
37- 41 F5.2 s RAs Aim point right ascension (J2000.0) (2)
43 A1 --- DE- Aim point declination sign (J2000.0) (2)
44- 45 I2 deg DEd Aim point declination (J2000.0) (2)
47- 48 I2 arcmin DEm Aim point declination (J2000.0) (2)
50- 53 F4.1 arcsec DEs Aim point declination (J2000.0) (2)
55- 59 F5.1 deg Roll Roll angle (3)
61- 62 A2 --- Mode Observation mode
(F = Faint mode ; VF = Very Faint mode)
64- 75 A12 --- Pipeline Version of the CXC pipeline software used
for basic processing of the data
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Note (1): All observations were continuous. These times have been
corrected for the lost exposure due to the readout time per CCD frame
and also reflect the total exposure after the data affected by high
background have been removed. The short time intervals with bad
satellite aspect are negligible and have not been removed.
For North Field, the total exposure time for the 20 observations is 1.945Ms.
For South Field, the total exposure time for the 11 observations is 939.4ks.
Note (2): In North Field, the average aim point, weighted by exposure time,
is RA(J2000.0) = 12h 36min 45.7s, DE(J2000.0) = +62° 13' 58".
In South Field, the average aim point, weighted by exposure time,
is RA(J2000.0) = 3h 32min 28.2s, DE(J2000.0) = -27° 48' 36";
individual aim points are offset by 5"-30" from the average aim point.
Note (3): Roll angle describes the orientation of the Chandra instruments
on the sky. The angle is between 0°-360°, and it increases to
the west of north (opposite to the sense of traditional position angle).
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Byte-by-byte Description of file: cdfn.dat cdfs.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- [ABB2003] Source number (G1)
5- 6 I2 h RAh X-ray hour of right ascension (J2000)
8- 9 I2 min RAm X-ray minute of right ascension (J2000)
11- 15 F5.2 s RAs X-ray second of right ascension (J2000)
17 A1 --- DE- Sign of the X-ray declination (J2000)
18- 19 I2 deg DEd X-ray degree of declination (J2000)
21- 22 I2 arcmin DEm X-ray arcminute of declination (J2000)
24- 27 F4.1 arcsec DEs X-ray arcsecond of declination (J2000)
29- 31 F3.1 arcsec PosErr Position error (80%-90% confidence level)
33- 37 F5.2 arcmin OAngle Off-axis angle
39 A1 --- l_C0.5-8 Limit flag on C0.5-8
40- 46 F7.1 ct C0.5-8 The 0.5-8.0 keV band counts
48- 52 F5.1 ct E_C0.5-8 ? The upper 1 σ error in C0.5-8
54- 58 F5.1 ct e_C0.5-8 ? The lower 1 σ error in C0.5-8
60- 61 A2 --- f_C0.5-8 Flag on C0.5-8 (2)
63 A1 --- l_C0.5-2 Limit flag on C0.5-2
64- 70 F7.1 ct C0.5-2 The 0.5-2 keV band counts
72- 76 F5.1 ct E_C0.5-2 ? The upper 1 σ error in C0.5-2
78- 82 F5.1 ct e_C0.5-2 ? The lower 1 σ error in C0.5-2
84- 85 A2 --- f_C0.5-2 Flag on C0.5-2 (2)
87 A1 --- l_C2-8 Limit flag on C2-8
88- 93 F6.1 ct C2-8 The 2-8 keV band counts
95- 98 F4.1 ct E_C2-8 ? The upper 1 σ error in C2-8
100-103 F4.1 ct e_C2-8 ? The lower 1 σ error in C2-8
105-106 A2 --- f_C2-8 ? Flag on C2-8 (2)
108 A1 --- l_C0.5-1 Limit flag on C0.5-1
109-114 F6.1 ct C0.5-1 The 0.5-1 keV band counts
116-119 F4.1 ct E_C0.5-1 ? The upper 1 σ error in C0.5-1
121-124 F4.1 ct e_C0.5-1 ? The lower 1 σ error in C0.5-1
126 A1 --- f_C0.5-1 Flag on C0.5-1R (2)
128 A1 --- l_C1-2 Limit flag on C1-2
129-135 F7.1 ct C1-2 The 1-2 keV band counts
137-141 F5.1 ct E_C1-2 ? The upper 1 σ error in C1-2
143-147 F5.1 ct e_C1-2 ? The lower 1 σ error in C1-2
149 A1 --- f_C1-2 Flag on C1-2 (2)
151 A1 --- l_C2-4 Limit flag on C2-4
152-157 F6.1 ct C2-4 The 2-4 keV band counts
159-162 F4.1 ct E_C2-4 ? The upper 1 σ error in C2-4
164-167 F4.1 ct e_C2-4 ? The lower 1 σ error in C2-4
169 A1 --- f_C2-4 Flag on C2-4 (2)
171 A1 --- l_C4-8 Limit flag on C4-8
172-177 F6.1 ct C4-8 The 4-8 keV band counts
179-182 F4.1 ct E_C4-8 ? The upper 1 σ error in C4-8
184-187 F4.1 ct e_C4-8 ? The lower 1 σ error in C4-8
189 A1 --- f_C4-8 Flag on C4-8 (2)
191-197 A7 --- Notes Notes on the source (3)
199-204 F6.1 ks Exp Effective exposure (4)
206 A1 --- l_Ratio1 Limit flag on Ratio1
207-211 F5.2 --- Ratio1 ? F(2-8)/F(0.5-2) count-rate ratio (5)
213-217 F5.2 --- E_Ratio1 ? The upper 1 σ error in Ratio1 (6)
219-222 F4.2 --- e_Ratio1 ? The lower 1 σ error in Ratio1 (6)
224 A1 --- l_Sp+Index Limit flag on Sp+Index
225-229 F5.2 --- Sp+Index Power-law model effective photon index (7)
231 A1 --- f_Sp+Index Flag on Sp+Index (8)
233-236 F4.2 --- E_Sp+Index ? The upper 1 σ error in Sp+Index
238-241 F4.2 --- e_Sp+Index ? The lower 1 σ error in Sp+Index
243 A1 --- l_F0.5-8 Limit flag on F0.5-8
244-249 F6.2 10-18W/m2 F0.5-8 Flux in the 0.5-8.0 keV band (9)
251 A1 --- l_F0.5-2 Limit flag on F0.5-2
252-256 F5.2 10-18W/m2 F0.5-2 Flux in the 0.5-2 keV band (9)
258 A1 --- l_F2-8 Limit flag on F2-8
259-264 F6.2 10-18W/m2 F2-8 Flux in the 2-8 keV band (9)
266 A1 --- l_F0.5-1 Limit flag on F0.5-1
267-271 F5.2 10-18W/m2 F0.5-1 Flux in the 0.5-1 keV band (9)
273 A1 --- l_F1-2 Limit flag on F1-2
274-278 F5.2 10-18W/m2 F1-2 Flux in the 1-2 keV band (9)
280 A1 --- l_F2-4 Limit flag on F2-4
281-285 F5.2 10-18W/m2 F2-4 Flux in the 2-4 keV band (9)
287 A1 --- l_F4-8 Limit flag on F4-8
288-293 F6.2 10-18W/m2 F4-8 Flux in the 4-8 keV band (9)
295 A1 --- l_Ratio2 Limit flag on Ratio2
296-301 F6.2 --- Ratio2 ? F(1-2)/F(0.5-1) count-rate ratio (3)
303-307 F5.2 --- E_Ratio2 ? The upper 1 σ error in Ratio2 (4)
309-313 F5.2 --- e_Ratio2 ? The lower 1 σ error in Ratio2 (4)
315 A1 --- l_Ratio3 Limit flag on Ratio3
316-320 F5.2 --- Ratio3 ? F(4-8)/F(2-4) count-rate ratio (3)
322-325 F4.2 --- E_Ratio3 ? The upper 1 σ error in Ratio3 (4)
327-330 F4.2 --- e_Ratio3 ? The lower 1 σ error in Ratio3 (4)
332 A1 --- l_Ratio4 Limit flag on Ratio4
333-336 F4.2 --- Ratio4 ? F(2-4)/F(1-2) count-rate ratio (3)
338-341 F4.2 --- E_Ratio4 ? The upper 1 σ error in Ratio4 (4)
343-346 F4.2 --- e_Ratio4 ? The lower 1 σ error in Ratio4 (4)
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Note (2): Note on band counts:
a = Source was detected with the restricted ACIS grade set with a
probability threshold of 10-7;
b = Source was detected with the standard ASCA grade set with a
probability threshold of 10-5;
c = Source positional offset >2.5" from the primary source position.
Note (3): Notes:
H = Denotes objects lying in the HDF-N (see Fig. 2);
O = Refers to objects that have large cross-band positional offsets
(>2.5") - all but one of these sources lie at off-axis angles
of >6', and the flagged counterpart may not be associated with
the main counterpart in some cases;
M = Refers to sources where the photometry was performed manually;
S = Refers to close double sources where manual separation was required;
R = Refers to radio-detected sources that were used in determining
the astrometric accuracy (see section 3.3);
HB3 = Refers to a detection in the 6-8keV band.
Note (4): Derived from the full-band exposure map.
Note (5): Corrected for differential vignetting between the bands using
the appropriate exposure maps.
Note (6): Calculated following the "numerical method" described in
section 1.7.3 of Lyons (1991, Data Analysis for Physical Science
Students, Cambridge: Cambridge Univ. Press); this avoids the failure
of the standard approximate variance formula when the number of counts
is small (see section 2.4.5 of Eadie et al., 1971, Statistical Methods
in Experimental Physics, Amsterdam: North-Holland). Note that the
error distribution is not Gaussian when the number of counts is small.
Note (7): With the Galactic column density, taking into account the
continuous ACIS quantum efficiency degradation. The effective photon
index has been calculated based on Rat when the number of counts is
not low.
Note (8): Note on photon index:
a = Photon index set to given value because of low number of counts.
Note (9): In units of 10-15ergs/s/cm2. Not corrected for absorption
by the Galaxy or material intrinsic to the source; however, the fluxes
have been adjusted to take into account the continuous ACIS quantum
efficiency degradation.
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Byte-by-byte Description of file: cdfn-sup.dat cdfs-sup.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 A3 --- [ABB2003] Source number (G1)
5- 6 I2 h RAh X-ray hour of right ascension (J2000)
8- 9 I2 min RAm X-ray minute of right ascension (J2000)
11- 15 F5.2 s RAs X-ray second of right ascension (J2000)
17 A1 --- DE- Sign of the X-ray declination (J2000)
18- 19 I2 deg DEd X-ray degree of declination (J2000)
21- 22 I2 arcmin DEm X-ray arcminute of declination (J2000)
24- 27 F4.1 arcsec DEs X-ray arcsecond of declination (J2000)
29- 31 F3.1 arcsec PosErr Position error (90% confidence level)
33- 37 F5.2 arcmin OAngle Off-axis angle
39 A1 --- l_C0.5-8 Limit flag on C0.5-8
40- 44 F5.1 ct C0.5-8 The 0.5-8.0 keV band counts
46- 49 F4.1 ct e_C0.5-8 ? The 1 σ error in C0.5-8
51 A1 --- f_C0.5-8 Flag on C0.5-8 (2)
53 A1 --- l_C0.5-2 Limit flag on C0.5-2
54- 58 F5.1 ct C0.5-2 The 0.5-2 keV band counts
60- 62 F3.1 ct e_C0.5-2 ? The 1 σ error in C0.5-2
65 A1 --- f_C0.5-2 Flag on C0.5-2 (2)
67 A1 --- l_C2-8 Limit flag on C2-8
68- 72 F5.1 ct C2-8 The 2-8 keV band counts
74- 76 F3.1 ct E_C2-8 ? The 1 σ error in C2-8
78 A1 --- f_C2-8 Flag on C2-8 (2)
80 A1 --- l_C0.5-1 Limit flag on C0.5-1
81- 85 F5.1 ct C0.5-1 The 0.5-1 keV band counts
87- 89 F3.1 ct e_C0.5-1 ? The 1 σ error in C0.5-1
91 A1 --- f_C0.5-1 Flag on C0.5-1 (2)
93 A1 --- l_C1-2 Limit flag on C1-2
94- 98 F5.1 ct C1-2 The 1-2 keV band counts
100-102 F3.1 ct e_C1-2 ? The 1 σ error in C1-2
104 A1 --- f_C1-2 Flag on C1-2 (2)
106 A1 --- l_C2-4 Limit flag on C2-4
107-111 F5.1 ct C2-4 The 2-4 keV band counts
113-115 F3.1 ct e_C2-4 ? The 1 σ error in C2-4
117 A1 --- f_C2-4 Flag on C2-4 (2)
119 A1 --- l_C4-8 Limit flag on C4-8
120-124 F5.1 ct C4-8 The 4-8 keV band counts
126-128 F3.1 ct e_C4-8 ? The 1 σ error in C4-8
130 A1 --- f_C4-8 Flag on C4-8 (2)
132-133 I2 h RAo.h Optical hour of right ascension (J2000)
135-136 I2 min RAo.m Optical minute of right ascension (J2000)
138-142 F5.2 s RAo.s Optical second of right ascension (J2000)
144 A1 --- DEo.- Sign of the optical declination (J2000)
145-146 I2 deg DEo.d Optical degree of declination (J2000)
148-149 I2 arcmin DEo.m Optical arcminute of declination (J2000)
151-154 F4.1 arcsec DEo.s Optical arcsecond of declination (J2000)
156-158 F3.1 arcsec O-X The optical and X-ray source offset
160-163 F4.1 mag Rmag The Vega-based R-band magnitude
165-171 F7.5 --- FProb ? The false-match probability (3)
173 A1 --- Notes Notes on the source (4)
176-181 F6.1 ks Exp Effective exposure (5)
183 A1 --- l_F0.5-8 Limit flag on F0.5-8
184-188 F5.2 10-18W/m2 F0.5-8 Flux in the 0.5-8.0 keV band (6)
190 A1 --- l_F0.5-2 Limit flag on F0.5-2
191-195 F5.2 10-18W/m2 F0.5-2 Flux in the 0.5-2 keV band (6)
197 A1 --- l_F2-8 Limit flag on F2-8
198-202 F5.2 10-18W/m2 F2-8 Flux in the 2-8 keV band (6)
204 A1 --- l_F0.5-1 Limit flag on F0.5-1
205-209 F5.2 10-18W/m2 F0.5-1 Flux in the 0.5-1 keV band (6)
211 A1 --- l_F1-2 Limit flag on F1-2
212-216 F5.2 10-18W/m2 F1-2 Flux in the 1-2 keV band (6)
218 A1 --- l_F2-4 Limit flag on F2-4
219-223 F5.2 10-18W/m2 F2-4 Flux in the 2-4 keV band (6)
225 A1 --- l_F4-8 Limit flag on F4-8
226-230 F5.2 10-18W/m2 F4-8 Flux in the 4-8 keV band (6)
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Note (2): Note on band counts:
a = Source was detected with the restricted ACIS grade set with a
probability threshold of 10-5.
b = Source positional offset >2.5" from the primary source position.
Note (3): This should be multiplied by 10-5 to calculate the boosted
X-ray significance.
Note (4): Notes:
L = Refers to objects where the X-ray source lies >1.5" from the
centroid of the optical source but is still within the extent of
the optical emission (see section 3.4.2);
H = Denotes objects lying in the HDF-N (see Fig. 2).
O = Refers to objects that have large cross-band positional offsets
(>2.5") - all but one of these sources lie at off-axis angles
of >6', and the flagged counterpart may not be associated with
the main counterpart in some cases.
Note (5): Derived from the full-band exposure map.
Note (6): In units of 10-15ergs/s/cm2. Fluxes have been calculated
assuming a photon index = 2.0. The fluxes have not been corrected for
absorption by the Galaxy or material intrinsic to the source; however,
the fluxes have been adjusted to take into account the continuous ACIS
quantum efficiency degradation.
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Global notes:
Note (G1): Sources are listed in order of increasing right ascension.
table3[ab].dat table7[ab].dat: [ABB2003] CDFN NNN in Simbad
tablea2[ab].dat tablea3[ab].dat: [ABB2003] CDFS NNN in Simbad
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Nomenclature Notes:
Tables 3: <[ABB2003] CDFN NNN> (Nos 1-503) =
Tables 7: <[ABB2003] CDFN SNN> (Nos S1-S79) =
Tables A2: <[ABB2003] CDFS NNN> (Nos 1-326) =
Tables A3: <[ABB2003] CDFS SNN> (Nos S1-S42) =
History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Bauer [CDS] 26-Sep-2003