J/MNRAS/343/293 ELAIS deep X-ray survey. I. (Manners+, 2003)
The ELAIS deep X-ray survey. I. Chandra source catalogue and first results.
Manners J.C., Johnson O., Almaini O., Willott C.J., Gonzalez-Solares E.,
Lawrence A., Mann R.G., Perez-Fournon I., Dunlop J.S., Mcmahon R.G.,
Oliver S.J., Rowan-Robinson M., Serjeant S.
<Mon. Not. R. Astron. Soc., 343, 293-305 (2003)>
=2003MNRAS.343..293M 2003MNRAS.343..293M
ADC_Keywords: Surveys ; X-ray sources
Mission_Name: Chandra
Keywords: catalogues - surveys - galaxies: active - X-rays: diffuse background -
X-rays: galaxies - X-rays: general
Abstract:
We present an analysis of two deep (75ks) Chandra observations of the
European Large Area Infrared Space Observatory (ISO) Survey (ELAIS)
fields N1 and N2 as the first results from the ELAIS deep X-ray
survey. This survey is being conducted in well-studied regions with
extensive multiwavelength coverage. Here we present the Chandra source
catalogues along with an analysis of source counts, hardness ratios
and optical classifications. A total of 233 X-ray point sources are
detected in addition to two soft extended sources, which are found to
be associated with galaxy clusters. An overdensity of sources is found
in N1 with 30 per cent more sources than N2, which we attribute to
large-scale structure. A similar variance is seen between other deep
Chandra surveys. The source count statistics reveal an increasing
fraction of hard sources at fainter fluxes. The number of galaxy-like
counterparts also increases dramatically towards fainter fluxes,
consistent with the emergence of a large population of obscured
sources.
Description:
The ELAIS Deep X-ray Survey (EDXS) is being conducted in the northern
ELAIS regions N1 and N2. The Chandra data consist of approximately 75
ks exposures in each field. Region N1 was observed on 2000 August 3-4
(OBS_ID 888) and N2 on 2000 August 2-3 (OBS_ID 887). The nominal
aimpoints were: N1, 16:10:20.11 +54:33:22.3; and
N2, 16:36:46.99 +41:01:33.7. The ACIS-I chips were used with the
addition of ACIS-S2 and ACIS-S4.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 113 130 Chandra sources in the ELAIS N1 field
table2.dat 113 103 Chandra sources in the ELAIS N2 field
list.dat 412 531 Sources detected in the 0.5-8keV, 0.5-2keV
and 2-8keV band images
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See also:
B/chandra : The Chandra Archive Log (CXC, 2002)
J/AJ/122/2810 : Chandra Deep Field North Survey. V. (Brandt+, 2001)
J/ApJS/139/369 : Chandra Deep Field South. 1 Ms catalog (Giacconi+, 2002)
J/AJ/126/632 : UBVRIz'HK' photometry of 2Ms CDFN X-ray sources
(Barger+, 2003)
J/A+A/329/482 : The ROSAT Deep Survey. I. (Hasinger+, 1998)
J/A+A/379/798 : ELAIS Hα emitting galaxies (Pascual+, 2001)
J/MNRAS/302/222 : ISO ELAIS 20cm VLA survey regions (Ciliegi+, 1999)
J/MNRAS/305/297 : ISO ELAIS 1.4GHz survey (Gruppioni+, 1999)
J/MNRAS/325/1173 : ISO ELAIS 15µm survey (Lari+, 2001)
Byte-by-byte Description of file: table1.dat table2.dat
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Bytes Format Units Label Explanations
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1- 6 A6 --- ID Identification number (N1_NNN or N2_NNN)
8- 23 A16 --- CXOEN CXOEN1 (table 1) or CXOEN2 (table2)
designation, JHHMMSS.s+DDMMSS
25- 26 I2 h RAh Right ascension (J2000)
28- 29 I2 min RAm Right ascension (J2000)
31- 35 F5.2 s RAs Right ascension (J2000)
37 A1 --- DE- Declination sign (J2000)
38- 39 I2 deg DEd Declination (J2000)
41- 42 I2 arcmin DEm Declination (J2000)
44- 47 F4.1 arcsec DEs Declination (J2000)
49- 52 F4.2 arcsec e_Pos Error in position
54- 59 F6.1 ct NCount Net counts
61- 65 F5.1 --- S/N Signal-to-noise ratio
67 A1 --- l_F0.5-8keV Limit flag on F0.5-2keV
68- 72 F5.2 10-17W/m2 F0.5-8keV Flux at (0.5-8keV) (in 10-17erg/cm2/s)
74- 77 F4.2 10-17W/m2 e_F0.5-8keV ? rms uncertainty on F0.5-8keV
79 A1 --- l_F0.5-2keV Limit flag on F0.5-2keV
80- 84 F5.2 10-17W/m2 F0.5-2keV ? Flux at (0.5-2keV) (in 10-17erg/cm2/s)
86- 89 F4.2 10-17W/m2 e_F0.5-2keV ? rms uncertainty on F0.5-2keV
91 A1 --- l_F2-8keV Limit flag on F2-8keV
92- 96 F5.2 10-17W/m2 F2-8keV ? Flux at (2-8keV) (in 10-17erg/cm2/s)
98-101 F4.2 10-17W/m2 e_F2-8keV ? rms uncertainty on F2-8keV
103-107 F5.2 --- HR Hardness ratio
109-112 F4.2 --- e_HR rms uncertainty on HR
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Byte-by-byte Description of file: list.dat
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Bytes Format Units Label Explanations
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1- 6 A6 --- ID Identification number (N1_NNN or N2_NNN)
8- 12 A5 keV Det Detection interval (0.5-2, 0.5-8 or 2-8keV)
14- 15 I2 h RAh Right ascension (J2000) (1)
16 A1 --- --- [:]
17- 18 I2 min RAm Right ascension (J2000) (1)
19 A1 --- --- [:]
20- 26 F7.4 s RAs Right ascension (J2000) (1)
28 A1 --- DE- Declination sign (J2000)(1)
29- 30 I2 deg DEd Declination (J2000)(1)
31 A1 --- --- [:]
32- 33 I2 arcmin DEm Declination (J2000)(1)
34 A1 --- --- [:]
35- 40 F6.3 arcsec DEs Declination (J2000)(1)
42- 44 I3 --- Rank Rank, in order of decreasing S/N
46- 56 E11.5 deg e_RAs Error on right ascension of X-ray centroid
(does not include astrometric error)
58- 68 E11.5 deg e_DEs Error on declination of X-ray centroid
(does not include astrometric error)
70- 84 F15.10 pix Xpos X-ray centroid position of unbinned Chandra
image
86-100 F15.10 pix Ypos X-ray centroid position of unbinned Chandra
image
102-117 F16.14 pix e_Xpos Error on centroid position
119-134 F16.14 pix e_Ypos Error on centroid position
136-139 I4 --- Npix2 Number of 0.984" (i.e. 2x2 binned image)
pixels in WAVDETECT 'source cell'
141-155 F15.10 ct Nct Background subtracted source counts within
the 'source cell'
157-169 F13.10 ct e_Nct Error on source counts
171-188 F18.14 ct BKGct Background counts within the 'source cell'
190-205 F16.14 ct e_BKGct Error on background counts
207-217 E11.5 ct/cm2/s CRate Source count rate in 'source cell'
219-229 E11.5 ct/cm2/s e_CRate Error on source count rate
231-241 E11.5 ct/cm2/s BKGrate Background count rate in 'source cell'
243-253 E11.5 ct/cm2/s e_BKGrate Error on background count rate
255-268 F14.10 cm+2 EffArea Effective area of detector at source
position
270-286 F17.14 cm+2 e_EffArea Error on effective area
288-301 F14.10 --- S/N Signal-to-noise as defined in paper I (2)
303-319 F17.14 arcsec PSFSize Estimated size of detector PSF at source
location: radius (in arcseconds) of the
circle which encompasses 39.3% of the total
counts of an unresolved source
321-336 F16.14 --- PSFRatio Approximate ratio of source size to
detector PSF size
338-350 F13.10 arcsec MajAxis Approximate 3 sigma size of
source major axis
353-369 F17.14 arcsec MinAxis Approximate 3 sigma size of
source minor axis
371-384 E14.10 deg PA Rotation angle of estimated source ellipse
386-388 I3 --- Comp Component number
390-400 E11.5 mW/m2 Flux Background subtracted source flux in
erg/cm2/s, calculated for the relevant
band assuming a photon index of =1.7, (2)
402-412 E11.5 mW/m2 e_Flux Error on Flux
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Note (1): Astrometrically corrected source coordinates (J2000 Equinox,
See paper I, Gonzalez-Solares et al., in preparation, section 4)
Note (2): See paper I, Gonzalez-Solares et al., in preparation, section 4
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History:
Copied at http://www.roe.ac.uk/~jcm/edxs/
(End) Patricia Bauer [CDS] 08-Jan-2004