J/ApJS/238/23 Chandra X-ray point sources in Abell 133 (Shin+, 2018)
A catalog of X-ray point sources in the Abell 133 region.
Shin J., Plotkin R.M., Woo J.-H., Gallo E., Mulchaey J.S.
<Astrophys. J. Suppl. Ser., 238, 23 (2018)>
=2018ApJS..238...23S 2018ApJS..238...23S
ADC_Keywords: Clusters, galaxy; X-ray sources; Photometry, UBV
Keywords: galaxies: active ; galaxies: clusters: individual (Abell 133) ;
X-rays: galaxies ; X-rays: galaxies: clusters
Abstract:
As an evolutionary phase of galaxies, active galactic nuclei (AGNs)
over a large range of redshifts have been utilized for understanding
cosmic evolution. In particular, the population and evolution of AGNs
have been investigated through the study of the cosmic X-ray
background in various fields. As one of the deep fields observed by
Chandra, with a total of 2.8Ms exposures, Abell 133 is a special
region for investigating AGNs, providing a testbed for probing the
environmental effects on AGN triggers, since cluster environments can
be different from field environments. The achieved flux limits of data
at the 50% completeness levels of 6.95x10-16, 1.43x10-16, and
1.57x10-15erg/s/cm2 are 0.5-8, 0.5-2, and 2-8keV. Using the
wavdetect and no-source binomial probability (i.e., p<0.007), we
analyze the combined Chandra image, detecting 1617 (in 0.5-8keV), 1324
(in 0.5-2keV), and 1028 (in 2-8keV) X-ray point sources in the Abell
133 region. Here, we present the X-ray point source catalog with the
source fluxes, which can be combined with multiwavelength data for
future works. We find that the number count distribution of the X-ray
point sources is well reproduced with a broken power-law model, while
the best-fit model parameters are sensitive to the fitting range of
the number count distribution. Finally, we find an excess of number
density (a decrease of AGN fraction) at the central region of the
cluster, which reflects the effect of dense environments on AGN
triggers, a finding similar to those of other studies of galaxy
clusters.
Description:
We searched the Chandra archive for observations covering Abell 133
cluster of galaxies at z=0.0566, and found a total of 2.8Ms exposures
split over 33 separate observations (see Table 1). All observations
were taken with the Advanced CCD Imaging Spectrometer (ACIS). To cover
the large extent of the Abell 133 cluster, which has R200=26.6', the
majority of Chandra observations were taken as a mosaic (for
reference, the ACIS-I field of view is 16.9'x16.9').
We detect 1617, 1324, and 1028 X-ray point sources in the full, soft,
and hard bands.
To improve the accuracy of the positions of the detected X-ray point
sources, we applied an astrometry correction by searching for optical
counterparts, using archival images from the Canada-France-Hawaii
telescope (CFHT). Eleven g-band images were taken as a mosaic to cover
1 square degree, with a total exposure time of 1320s and 5σ
limiting magnitude of 26.5.
To identify optical counterparts, we consider 15093 optical points
sources with rmag<22.5 in our CFHT images. Out of 1951 X-ray
detections, we found optical counterparts for 310 sources by adopting
a matching radius of 1.5"; see section 3.4.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 44 33 Chandra observing log for Abell 133
table2.dat 280 1951 Main Chandra source catalog
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See also:
B/cfht : Log of CFHT Exposures (CADC, 1979-)
B/chandra : The Chandra Archive Log (CXC, 1999-2014)
J/AJ/126/539 : The Chandra Deep Fields North and South (Alexander+, 2003)
J/ApJ/591/53 : I photometry of Cl 0024+16 (Treu+, 2003)
J/ApJ/634/977 : Redshifts in Cl 0024+16 members (Moran+, 2005)
J/ApJS/179/19 : CDFS survey: 2 Ms source catalogs (Luo+, 2008)
J/ApJS/184/158 : Chandra COSMOS survey I. (Elvis+, 2009)
J/MNRAS/392/1509 : Distribution of AGNs in galaxy clusters (Gilmour+, 2009)
J/ApJ/704/1586 : BCGs with radio AGN (Sun, 2009)
J/ApJS/195/10 : The CDF-S survey: 4Ms source catalogs (Xue+, 2011)
J/MNRAS/419/2095 : HMXBs in nearby galaxies (Mineo+, 2012)
J/ApJS/224/40 : Catalog of Chandra ACIS point like sources (Wang+, 2016)
J/ApJS/228/2 : Chandra Deep Field-South survey: 7Ms sources (Luo+, 2017)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 5 I5 --- ObsID [2203/14354] Chandra observation ID
7-17 A11 "Y/M/D" Date UT date of observation start
19-24 F6.2 ks Exp [33/177] Exposure time
26-31 F6.3 deg RAdeg [15.3/16.1] Right ascension (J2000) (1)
33-39 F7.3 deg DEdeg [-22.3/-21.5] Declination (J2000) (1)
41-42 I2 --- Cycle [2/12] Observation cycle
44-44 I1 --- Ref [1/4] References (2)
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Note (1): The pointing centers of each Chandra observation.
Note (2): Reference where data were first published as follows:
1 = Fujita et al. (2002ApJ...575..764F 2002ApJ...575..764F),
2 = Vikhlinin et al. (2005ApJ...628..655V 2005ApJ...628..655V),
3 = Sun (2009, J/ApJ/704/1586),
4 = Morandi & Cui (2014MNRAS.437.1909M 2014MNRAS.437.1909M).
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 5 I5 --- Seq [1/1951] Sequence number
7- 16 F10.5 deg RAdeg [15.1/16.2] Right ascension of
X-ray point source (J2000)
18- 27 F10.5 deg DEdeg [-22.4/-21.4] Declination of
X-ray point source (J2000)
29- 36 F8.1 ct FBcts [4/9999] Net counts in full (0.5-8keV) band
38- 45 F8.1 ct e_FBcts [2/164]?=-9999 Lower uncertainty in FB
47- 54 F8.1 ct E_FBcts [5/167]?=-9999 Upper uncertainty in FB
56- 63 F8.1 ct SBcts [3/6894] Net counts in soft (0.5-2keV) band
65- 72 F8.1 ct e_SBcts [2/136]?=-9999 Lower uncertainty in SB
74- 81 F8.1 ct E_SBcts [5/139]?=-9999 Upper uncertainty in SB
83- 90 F8.1 ct HBcts [5/2940] Net counts in hard (2-8keV) band
92- 99 F8.1 ct e_HBcts [3/89]?=-9999 Lower uncertainty in HB
101-108 F8.1 ct E_HBcts [5/91]?=-9999 Upper uncertainty in HB
110-116 F7.2 --- HR [-1/1]? Hardness ratio (1)
118-124 F7.2 --- e_HR [0.02/0.5]? Lower uncertainty in HR
126-132 F7.2 --- E_HR [0.02/0.9]? Upper uncertainty in HR
134-143 F10.5 deg RAOdeg [15.1/16.2]? Right ascension of optical
counterpart (J2000)
145-154 F10.5 deg DEOdeg [-22.3/-21.4]? Declination of optical
counterpart (J2000)
156-162 F7.2 mag gmag [15.8/24.5]? CFHT g-band magnitude of
optical counterpart
164-170 F7.2 mag g-r [-0.5/2.3]? g-r color of optical counterpart
172-178 F7.2 --- alphaOX [1/2.8]? Optical to X-ray spectral index
180-187 F8.1 ct FBraw [3/10022] Raw counts in full band
189-196 F8.1 ct FBbkg [0/376] Background counts in full band
198-205 F8.1 ct SBraw [0/6928] Raw counts in soft band
207-214 F8.1 ct SBbkg [0/157] Background counts in soft band
216-223 F8.1 ct HBraw [0/2968] Raw counts in hard band
225-232 F8.1 ct HBbkg [0/147] Background counts in hard band
234-239 F6.1 ks FBexp [52/492] Effective Exposure time in
full band
241-246 F6.1 ks SBexp [44/472] Effective Exposure time in
soft band
248-253 F6.1 ks HBexp [51/491] Effective Exposure time in
hard band
255-262 F8.2 10-18W/m2 FBFlux [0.1/625] Net flux in full (0.5-8keV)
band (2)
264-271 F8.2 10-18W/m2 SBFlux [0.06/221] Net flux in soft (0.5-2keV)
band (2)
273-280 F8.2 10-18W/m2 HBFlux [0.4/335] Net flux in hard (2-8keV) band (2)
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Note (1): Where HR=(Hard-Soft)/(Hard+Soft).
Note (2): In units of 1e-15erg/cm2/s. Conversion factors from net count
rate to flux are 1.233e-11 (full band), 6.109e-12 (soft band),
and 2.214e-11 (hard band) erg/s/cm2 per 1 count/s.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 30-Nov-2018