J/A+A/693/A142 X-ray blazars without 4FGL-DR4 counterpart (Marchesi+, 2025)
A new look at the extragalactic Very High Energy sky: Searching for TeV-emitting
candidates among the X-ray bright, non-Fermi detected blazar population.
Marchesi S., Iuliano A., Prandini E., Da Vela P., Doro M., Loporchio S.,
Miceli D., Righi C., Zanin R., Bronzini E., Vignali C.
<Astron. Astrophys. 693, A142 (2025)>
=2025A&A...693A.142M 2025A&A...693A.142M (SIMBAD/NED BibCode)
ADC_Keywords: BL Lac objects ; Active gal. nuclei ; X-ray sources ; Gamma rays
Keywords: catalogs - virtual observatory tools - BL Lacertae objects: general -
quasars: supermassive black holes - gamma rays: galaxies
Abstract:
We present the results of a multi-wavelength study of blazars selected
from the 5th ROMABZCAT catalog. We selected from this sample a
subsample of 2435 objects having at least one counterpart in one of
the three main archival X-ray catalogs, which is, the fourth release
of the XMM-Newton Survey Science Catalogue, the second release of the
Chandra Source Catalog, and the second Swift X-ray Point Source
catalog of detections by Swift-XRT, or in the recently released
eROSITA-DE Data Release 1 catalog. We first searched for different
multi-wavelength trends between sources with a Gamma-ray counterpart
in the Fermi-LAT 14-year Source Catalog (4FGL-DR4) and sources lacking
one. We find that the non-4FGL sources are on average fainter both in
the X-rays and in the radio with respect to the 4FGL-detected ones,
but the two samples have similar X-ray-to-radio flux ratios, as well
as synchrotron peak frequencies. We then focused on the 1007
non-Gamma-ray detected population, to determine if there is a sample
of X-ray sources that could be TeV emitters. We find that a large
number of sources, mostly BL Lacs or BL Lacs with host-galaxy
contribution to the spectral energy distribution, have large
synchrotron peak frequency and X-ray to radio flux ratio, two
properties that characterize the vast majority of known TeV emitters.
With respect to these known TeV emitters, our targets have X-ray
fluxes ∼1 order of magnitude fainter. We then computed the 0.2-12keV
and 20GeV-300TeV fluxes for the known 5BZCAT TeV emitters, and
determined the existence of a direct correlation between X-ray and TeV
fluxes in the BL Lacs population. We used this trend to estimate the
VHE flux of our targets, and found a promising sample of sources for
follow-up observations with current or future, more sensitive,
Cherenkov telescopes, first and foremost the Cherenkov Telescope Array
Observatory.
Description:
Catalog of the 1007 blazars in the 5th ROMABZCAT catalog that have
been detected in the X-rays but do not have a counterpart in the
4FGL-DR4 Fermi-LAT gamma-ray catalog.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
catalog.dat 301 1007 Catalog of the 1007 sources without a
4FGL counterpart
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See also:
VII/274 : The Roma BZCAT - 5th edition (Massaro+, 2015)
IX/69 : XMM-Newton Serendipitous Source Catalogue 4XMM-DR13 (Webb+, 2023)
IX/58 : 2SXPS Swift X-ray telescope point source catalogue (Evans+, 2020)
IX/57 : The Chandra Source Catalog (CSC), Release 2.0 (Evans+, 2019)
J/A+A/682/A34 : SRG/eROSITA all-sky survey catalogs (eRASS1) (Merloni+, 2024)
Byte-by-byte Description of file: catalog.dat
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Bytes Format Units Label Explanations
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1- 14 A14 --- 5BZCAT 5BZCAT source ID, from Massaro et al.
(2015. Cat. VII/274) (ID_5BZCAT)
16- 17 I2 h RAh Right Ascension (J2000), 5BZCAT source
(RA_5BZCAT)
19- 20 I2 min RAm Right Ascension (J2000), 5BZCAT source
(RA_5BZCAT)
22- 26 F5.2 s RAs Right Ascension (J2000), 5BZCAT source
(RA_5BZCAT)
28 A1 --- DE- Declination sign (J2000), 5BZCAT source
(DEC_5BZCAT)
29- 30 I2 deg DEd Declination (J2000), 5BZCAT source
(DEC_5BZCAT)
32- 33 I2 arcmin DEm Declination (J2000), 5BZCAT source
(DEC_5BZCAT)
35- 39 F5.2 arcsec DEs Declination (J2000), 5BZCAT source
(DEC_5BZCAT)
41- 47 F7.3 --- z ?=-99 Source redshift (Redshift)
49- 51 A3 --- Type Object classification from the 5BZCAT
(BZB, BZG, BZQ, or BZU) (OBJECT_TYPE)
53- 57 F5.1 mag Rmag ?=-99 Optical, R-band AB magnitude of the
source, from the 5BZCAT (RMAG)
59- 65 F7.1 mJy F1.5GHz 1.4 GHz flux density of the source,
from the 5BZCAT (FLUX1P4GHZ)
67- 86 A20 --- 4XMDR13 Source ID from the 4XMM-DR13 catalog
(ID_4XMDR13)
88- 89 I2 h RAXh ? Right Ascension (J2000), 4XMM-DR13
counterpart (RA_4XMMDR13)
91- 92 I2 min RAXm ? Right Ascension (J2000), 4XMM-DR13
counterpart (RA_4XMMDR13)
94- 98 F5.2 s RAXs ? Right Ascension (J2000), 4XMM-DR13
counterpart (RA_4XMMDR13)
100 A1 --- DEX- Declination sign (J2000), 4XMM-DR13
counterpart (DEC_4XMMDR13)
101-102 I2 deg DEXd ? Declination (J2000), 4XMM-DR13
counterpart (DEC_4XMMDR13)
104-105 I2 arcmin DEXm ? Declination (J2000), 4XMM-DR13
counterpart (DEC_4XMMDR13)
107-111 F5.2 arcsec DEXs ? Declination (J2000), 4XMM-DR13
counterpart (DEC_4XMMDR13)
113-132 A20 --- 2CSC Source ID from the 2CSC catalog (ID_2CSC)
134-152 F19.15 deg RA2deg ? Right Ascension (J2000), 2CSC counterpart
(RA_2CSC)
154 A1 --- DE2- Declination sign (J2000), 2CSC counterpart
(DEC_2CSC)
155-156 I2 deg DE2d ? Declination (J2000), 2CSC counterpart
(DEC_2CSC)
158-159 I2 arcmin DE2m ? Declination (J2000), 2CSC counterpart
(DEC_2CSC)
161-165 F5.2 arcsec DE2s ? Declination (J2000), 2CSC counterpart
(DEC_2CSC)
167-188 A22 --- 2SXPS Source ID from the 2SXPS catalog (ID_2SXPS)
190-191 I2 h RASh ? Right Ascension (J2000), 2SXPS counterpart
(RA_2SXPS)
193-194 I2 min RASm ? Right Ascension (J2000), 2SXPS counterpart
(RA_2SXPS)
196-200 F5.2 s RASs ? Right Ascension (J2000), 2SXPS counterpart
(RA_2SXPS)
202 A1 --- DES- Declination sign (J2000), 2SXPS counterpart
(DEC_2SXPS)
203-204 I2 deg DESd ? Declination (J2000), 2SXPS counterpart
(DEC_2SXPS)
206-207 I2 arcmin DESm ? Declination (J2000), 2SXPS counterpart
(DEC_2SXPS)
209-213 F5.2 arcsec DESs ? Declination (J2000), 2SXPS counterpart
(DEC_2SXPS)
215-237 A23 --- eRASS1 Source ID from the eRASS1 catalog
(ID_eRASS1)
239-240 I2 h RARh ? Right Ascension (J2000), eRASS1
counterpart (RA_eRASS1)
242-243 I2 min RARm ? Right Ascension (J2000), eRASS1
counterpart (RA_eRASS1)
245-249 F5.2 s RARs ? Right Ascension (J2000), eRASS1
counterpart (RA_eRASS1)
251 A1 --- DER- Declination sign (J2000), eRASS1 counterpart
(DEC_eRASS1)
252-253 I2 deg DERd ? Declination, (J2000), eRASS1 counterpart
(DEC_eRASS1)
255-256 I2 arcmin DERm ? Declination, (J2000), eRASS1 counterpart
(DEC_eRASS1)
258-259 I2 arcsec DERs ? Declination, (J2000), eRASS1 counterpart
(DEC_eRASS1)
261-267 F7.3 [mW/m2] logF02-12 ? 0.2-12keV flux (in erg/s/cm2) from one
of the four X-ray catalogs, in this order
of priority: 4XMM-DR13, 2CSC, 2SXPS, eRASS1
(LogFlux02-12)
269-275 F7.3 [mW/m2] b_logF02-12 ? 90% confidence level lower boundary on
the 0.2-12keV flux (LogFlux02-12_lo)
277-283 F7.3 [mW/m2] B_logF02-12 ? 90% confidence level upper boundary on
the 0.2-12keV flux (LogFlux02-12_up)
285-292 F8.1 --- Ratio ? 0.2-12keV to 1.4GHz flux ratio
(Xraytoradiorat)
294-297 F4.1 [Hz] lognupeak ? Logarithm of the blazar SED synchrotron
peak computed using the Blazar Synchrotron
Tool, BlaST (nupeakBLAST)
299-301 F3.1 [Hz] e_lognupeak Uncertainty on the logarithm of the
blazar SED synchrotron peak computed using
the Blazar Synchrotron Tool, BlaST
(nupeakBLAST_err)
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Acknowledgements:
from Stefano Marchesi, stefano.marchesi(at)inaf.it
The research activities described in this paper were carried
out with contribution of the Next Generation EU funds within the
National Recovery and Resilience Plan (PNRR), Mission 4 - Education
and Research, Component 2 - From Research to Business (M4C2),
Investment Line 3.1 - Strengthening and creation of Research
Infrastructures, Project IR0000012 "CTA+ - Cherenkov Telescope
Array Plus".
(End) Patricia Vannier [CDS] 24-Dec-2024