J/A+A/692/A147 Soft X-ray Swift-XRT sources 3PBC counterparts (Kosiba+, 2024)
Swift-XRT follow-up analysis of unidentified hard X-ray sources.
Searching for soft X-ray counterparts of unidentified hard X-ray sources.
Kosiba M., Massaro F., Paggi A., Pena-Herazo H.A., Masetti N.,
Chavushyan V., Bottacini E., Werner N.
<Astron. Astrophys. 692, A147 (2024)>
=2024A&A...692A.147K 2024A&A...692A.147K (SIMBAD/NED BibCode)
ADC_Keywords: X-ray sources ;
Keywords: methods: data analyses - catalogs - X-rays: general
Abstract:
It has been established that the sources contributing to the cosmic
X-ray background (CXB) emission are mainly nearby active galactic
nuclei (AGNs), in particular those that are obscured. Thus, it is
important to fully identify the hard X-ray sky source population to
accurately characterize the individual contribution of different AGNs
to the overall CXB emission.
We present a follow-up analysis of all the 218 sources marked as
unidentified in our previous revision of the third release of the
Palermo Swift-BAT hard X-ray catalog (3PBC) based on our
multifrequency classification scheme. These 218 sources were
classified as unidentified in our previous analyses because they lack
an assigned low-energy counterpart.
We searched for soft X-ray counterparts of these 218 3PBC sources in
archival Swift-XRT observations obtained between 2005 January 1st and
2018 August 1st. In particular, we found 1213 archival Swift-XRT
observations for 192 of the 218 unidentified sources.
We found 93 possible Swift-XRT counterparts inside of the Swift-BAT
positional uncertainty regions. These correspond to 73 3PBC sources,
where 60 have only a single Swift-XRT detection and 13 sources have
multiple detections. We present a catalog of all the detected possible
counterparts of the yet unidentified hard X-ray sources to the
community as a catalog for future spectroscopic follow-up targets,
together with a short catalog of our classification of the ten sources
for which we found available spectra.
Description:
The candidate counterparts table is the final catalog table of our
work. It lists 93 candidate counterparts to the hard X-ray sources
originally detected in the 3PBC catalog. These counterparts are
obtained by crossmatching with the 3PBC sample of yet unidentified
sources lacking any lower energy counterpart to the Swift-XRT data.
This catalog table lists the 93 detections we found within the BAT
positional uncertainty. The table consists of 93 rows and 15 columns.
The column descriptions are the following: The 3PBC name; The XRT
candidate counterpart name; The X-ray detection flag; The right
ascension of the centroid; The declination of the centroid; The XRT
centroid positional uncertainty; The angular separation between the
XRT centroid and BAT centroid; The count rate; The delta of the count
rate; Signal to Noise (S/N) in full band (0.5-10keV); S/N in the hard
band (2-10keV); S/N in the soft band (0.5-2keV); The number of
observations, Nobs; the approximated total integrated exposure time,
Texp; The WISE name of the source if found in the WISE catalog.
The classified sources table is a short table of 10 candidate
counterparts for which we also found available spectra in the SDSS
archive. This table lists the 3PBC name of the corresponding BAT
source, the SDSS name, redshift and our classification based on the
spectral characteristics
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
candctp.dat 145 93 All 93 detected soft X-ray Swift-XRT sources
within the BAT positional uncertainty
class.dat 66 10 *Multiwavelength classification of the ten
counterparts with available spectra in the SDSS
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Note on class.dat: There are three sources with the same 3PBC name,
each corresponding to a different Swift-XRT soft X-ray detection.
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See also:
J/A+A/524/A64 : The 54-month Palermo BAT-survey catalogue (Cusumano+, 2010)
J/A+A/670/A171 : Second release of the Turin-SyCAT catalog (Kosiba+, 2023)
Byte-by-byte Description of file: candctp.dat
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Bytes Format Units Label Explanations
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1- 16 A16 --- 3PBC 3PBC name, 3PBCJHHMM.m+DDMM (3PBC_name)
18- 44 A27 --- XRT XRT candidate counterpart name,
SWXRTJHHMMSS.sss+DDMMSS.sss (XRT_detection)
46 A1 --- XDF [mx] X-ray detection flag (XDF) (1)
48- 49 I2 h RAh Centroid right ascension (J2000)
51- 52 I2 min RAm Centroid right ascension (J2000)
54- 58 F5.2 s RAs Centroid right ascension (J2000)
60 A1 --- DE- Centroid declination sign (J2000)
61- 62 I2 deg DEd Centroid declination (J2000)
64- 65 I2 arcmin DEm Centroid declination (J2000)
67- 71 F5.2 arcsec DEs Centroid declination (J2000)
73- 75 F3.1 arcsec ePos XRT centroid positional uncertainty
(sigma_XRT)
77- 81 F5.1 arcsec sepXRTBAT Angular separation between the XRT centroid
(angsep_XRTBAT)
83- 90 E8.3 ct/s CRate Count rate (count_rate)
92- 99 E8.3 ct/s e_CRate Count rate error (errcountrate)
101-104 F4.1 --- SNRfull Signal to Noise (S/N) in
full band (0.5-10keV) (SNR_full)
106-109 F4.1 --- SNRhard ?=- S/N in the
hard band (2-10keV) (SNR_hard)
111-114 F4.1 --- SNRsoft ?=- S/N in the
soft band (0.5-2keV) (SNR_soft)
116-118 I3 --- Nobs Number of observations (N_obs)
120-125 I6 s Texp Approximated total integrated
exposure time (T_exp)
127-145 A19 --- WISE WISE name of the source if found in the
WISE catalog (WISE_Name)
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Note (1): X-ray detection flag as follows:
x = exactly one soft Swift-XRT source detected inside of the BAT
positional uncertainty region of image of 3PBC source
m = more than one soft Swift-XRT source detected inside of the BAT
positional uncertainty region of image of 3PBC source
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Byte-by-byte Description of file: class.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 16 A16 --- 3PBC 3PBC name (3PBC_name)
18- 36 A19 --- SDSS SDSS name (SDSS_name)
38- 44 F7.5 --- z ?=- Redshift
46- 66 A21 --- Class Classification based on the spectral
characteristics (Class)
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Acknowledgements:
Matej Kosiba, matej.kosiba(at)gmail.com
History:
Kosiba et al., Paper I 2023A&A...670A.171K 2023A&A...670A.171K, Cat. J/A+A/670/A171
(End) Patricia Vannier [CDS] 27-Aug-2024