J/A+A/702/A34 eFEDS-DOG catalog (Noboriguchi+, 2025)
The X-ray statistical properties of dust-obscured galaxies detected by eROSITA.
Noboriguchi A., Ichikawa K., Toba Y., Dwelly T., Inayoshi K., Kawaguchi T.,
Liu T., Terashima Y., Ueda Y., Akiyama M., Brusa M., Buchner J., Kohno K.,
Merloni A., Nagao T., Salvato M., Suh H., Urrutia T.
<Astron. Astrophys. 702, A34 (2025)>
=2025A&A...702A..34N 2025A&A...702A..34N (SIMBAD/NED BibCode)
ADC_Keywords: Surveys; X-ray sources; Active gal. nuclei ; Radio sources ;
Photometry, SDSS ; Infrared
Keywords: galaxies: active - galaxies: evolution -
quasars: supermassive black holes - infrared: galaxies -
X-rays: galaxies
Abstract:
The tight relation between a supermassive black hole (SMBH) and host
galaxy masses suggests co-evolution of the SMBH with its host galaxy.
Dust-obscured galaxies (DOGs) are considered to be in a co-evolution
phase, with the associated active galactic nuclei (AGN) obscured by
dust and gas. Although the DOGs are thought to harbor rapidly growing
SMBHs, their X-ray statistical properties, crucial for understanding
the properties of obscuring gas as well as the accretion disk state
and the hot electron corona around the SMBHs, remain unexplored due to
the combination of the low number density of DOGs and the lack of
X-ray surveys achieving both of the wide-area and uniformly
high-sensitivity observations.
We construct a sample of X-ray-detected DOGs in the eROSITA Final
Equatorial Depth Survey (eFEDS) field and examine their X-ray
statistical properties.
To construct the DOGs sample, we combined data from Subaru/HSC SSP
(optical), VIKING (near-infrared), and WISE (mid-infrared) all-sky
surveys. We then cross-matched the sample with eROSITA-detected
sources to select X-ray-detected DOGs.
Our results reveal the discovery of 5738 IR-bright DOGs in the
footprint covered by both of the eFEDS and VIKING surveys (60deg2),
with 65 objects identified as X-ray-detected DOGs (eFEDS-DOGs). Among
them, 41 eFEDS-DOGs show a power-law slope in the near to mid-IR bands
(power-law DOGs), indicating dust-obscured AGN. The hydrogen column
density (NH) suggests that eFEDS-DOGs cover even unobscured AGN,
spanning 1020<NH/cm-2≲1023. On the other hand, the majority of
IR-bright DOGs are not detected by eROSITA, suggesting that most
IR-bright DOGs are heavily obscured by dust and gas with
NH/cm-2>1023. Therefore, eFEDS-DOGs, discovered thanks to the
wide-area survey by eROSITA, are newly found populations showing less
obscured phases among the lifetime of DOGs. This feature possibly
traces the onset of the decrease of the dust and gas obscuration phase
of AGN in DOGs; possibly caused by gas stripping/outflows in the AGN
feedback phase. Additionally, some eFEDS-DOGs exhibit deviations, down
to nearly 1.0dex below the monochromatic luminosity at 6um (L6um )
versus absorption-corrected intrinsic X-ray luminosity between
0.5-2keV (L(abs,corr)0.5-2keV) relation, suggesting that it may
signal high Eddington ratios reaching the Eddington limit. Such a
deviation could be realized only when the accretion disk is in a phase
of high Eddington ratios, possibly reaching Eddington limit. This
suggests that eFEDS-DOGs are prominent candidates for very rapidly
growing black holes reaching close to over the Eddington accretion
rate and just beginning the onset of intensive AGN feedback.
Description:
We have constructed the sample of 74 X-ray detected dust obscured
galaxies (DOGs) detected in the 0.5-2keV bands by the eROSITA/eFEDS
survey, and we call them "eFEDS detected DOGs".
From the eFEDS-detected DOGs, we further apply additional cut to
obtain the sample with reliable X-ray based parameters. We apply the
flags (CTP_quality ≥ 2, CTPREDSHIFTGRADE ≥ 3, and NHclass ≥ 2) to
select 65 objects, hereafter called "eFEDS-DOGs", presented in
tablea1.dat
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 364 65 eFEDS-DOG catalog
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See also:
J/ApJ/876/132 : IR-bright DOGs viewed with Subaru HSC (Noboriguchi+, 2019)
J/A+A/661/A1 : The eFEDS X-ray catalogs (V7.4) (Brunner+, 2022)
J/A+A/661/A3 : eFEDS counterparts to point-like sources (Salvato+, 2022)
J/A+A/661/A5 : The eFEDS AGN catalog (Liu+, 2022)
Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 23 A23 --- HSC HSC identifier, JHHMMSS.ss+DDMMSS.s
(HSC_ID)
25- 31 F7.3 deg RAdeg Right ascension (J2000) from HSC
coordinates (HSC_RA)
33- 40 F8.5 deg DEdeg Decination (J2000) from HSC coordinates
(HSC_DEC)
42- 46 F5.2 mag HSCg ?=- Subaru/HSC g-band magnitude (HSC_g)
48- 55 F8.6 mag e_HSCg ?=- Subaru/HSC g-band magnitude error
(HSCgerr)
57- 61 F5.2 mag HSCr Subaru/HSC r-band magnitude HSC g-band
magnitude (HSC_r)
63- 70 F8.6 mag e_HSCr Subaru/HSC r-band magnitude error
(HSCrerr)
72- 76 F5.2 mag HSCi Subaru/HSC i-band magnitude (HSC_i)
78- 85 F8.6 mag e_HSCi Subaru/HSC i-band magnitude error
(HSCierr)
87- 91 F5.2 mag HSCz Subaru/HSC z-band magnitude (HSC_z)
93-100 F8.6 mag e_HSCz Subaru/HSC z-band magnitude error
(HSCzerr)
102-106 F5.2 mag HSCy Subaru/HSC y-band magnitude (HSC_y)
108-115 F8.6 mag e_HSCy Subaru/HSC g-band magnitude error
(HSCyerr)
117-121 F5.2 mag VIKINGZ ?=- VIKING Z-band magnitude (VIKING_Z)
123-126 F4.2 mag e_VIKINGZ ?=- VIKING Z-band magnitude error
(VIKINGZerr)
128-132 F5.2 mag VIKINGY ?=- VIKING Y-band magnitude (VIKING_Y)
134-137 F4.2 mag e_VIKINGY ?=- VIKING Y-band magnitude error
(VIKINGYerr)
139-143 F5.2 mag VIKINGJ ?=- VIKING J-band magnitude (VIKING_J)
145-148 F4.2 mag e_VIKINGJ ?=- VIKING J-band magnitude error
(VIKINGJerr)
150-154 F5.2 mag VIKINGH ?=- VIKING H-band magnitude (VIKING_H)
156-159 F4.2 mag e_VIKINGH ?=- VIKING H-band magnitude error
(VIKINGHerr)
161-165 F5.2 mag VIKINGKs VIKING Ks-band magnitude (VIKING_Ks)
167-170 F4.2 mag e_VIKINGKs VIKING Ks-band magnitude error
(VIKINGKserr)
172-176 F5.2 mag WISEW1 WISE W1-band magnitude (WISE_W1)
178-185 F8.6 mag e_WISEW1 WISE W1-band magnitude error (WISEW1err)
187-191 F5.2 mag WISEW2 WISE W2-band magnitude (WISE_W2)
193-200 F8.6 mag e_WISEW2 WISE W2-band magnitude error (WISEW2err)
202 I1 --- l_WISEW2 [0/1] Upper limit flag WISE (WISEW2U_F)
204-208 F5.2 mag WISEW3 WISE W2-band magnitude (WISE_W3)
210-217 F8.6 mag e_WISEW3 WISE W3-band magnitude error (WISEW3err)
219 I1 --- l_WISEW3 [0/1] Upper limit flag WISE (WISEW3U_F)
221-225 F5.2 mag WISEW4 WISE W4-band magnitude (WISE_W4)
227-230 F4.2 mag e_WISEW4 WISE W4-band magnitude error (WISEW4err)
232 A1 --- MIRClass [012] MIR classification (MIR_CLASS) (1)
234-241 F8.6 --- alpha-grizy ?=- Spectral index, αoptgrizy
(ALPHA_GRIZY)
243-250 F8.6 --- alpha-gri ?=- Spectral index, αoptgri
(ALPHA_GRI)
252 A1 --- OptClass [01] Optical classification
(OPTICAL_CLASS) (2)
254-258 A5 --- ID-SRC ID of the sources in the eFEDS main X-ray
catalog (Brunner et al.,
2022A&A...661A...1B 2022A&A...661A...1B, Cat. J/A+A/661/A1)
260-271 E12.6 mW/m2 FobsS Observed flux in observed-frame 0.5-2.0keV
from Liu et al. (2022A&A...661A...5L 2022A&A...661A...5L,
Cat. J/A+A/661/A5) (FOBS0520)
273-284 E12.6 mW/m2 e_FobsS Observed flux in observed-frame 0.5-2.0keV
error from Liu et al.
(2022A&A...661A...5L 2022A&A...661A...5L, Cat. J/A+A/661/A5)
(FOBS0520_err)
286-292 F7.4 [10-7W] logLintS0 Absorption corrected intrinsic luminosity
in rest-frame 0.5-2.0keV from Liu et al.
(2022A&A...661A...5L 2022A&A...661A...5L, Cat. J/A+A/661/A5)
(Log10LINT0520_ABSCORR)
294-301 F8.6 [10-7W] e_logLintS0 Absorption corrected intrinsic luminosity
in rest-frame 0.5-2.0keV error from Liu
et al. (2022A&A...661A...5L 2022A&A...661A...5L,
Cat. J/A+A/661/A5)
(Log10LINT0520ABSCORRerr)
303-310 F8.6 --- z Redshift of the optical counterpart from
Salvato et al. (2022A&A...661A...3S 2022A&A...661A...3S,
Cat. J/A+A/661/A3) (REDSHIFT)
312 I1 --- q_z [3/5] Redshift Grade from Salvato et al.
(2022A&A...661A...3S 2022A&A...661A...3S, Cat. J/A+A/551/A3)
(REDSHIFT_GRADE)
314-320 F7.4 [10-7W] logLintS Absorption non-corrected luminosity in
rest-frame 0.5-2.0 keV
(Log10L0520_ABSNONCORR)
322-329 F8.6 [10-7W] e_logLintS Absorption non-corrected luminosity in
rest-frame 0.5-2.0 keV error
(Log10L0520ABSNONCORRerr)
331-337 F7.4 [cm-2] logNH Hydrogen column density (NH) from Liu et
al. (2022A&A...661A...5L 2022A&A...661A...5L,
Cat. J/A+A/661/A5) (Log10NH)
339-345 F7.4 [cm-2] logL6CIGALE Monochromatic luminosity at rest-frame 6um
(L6um) (Log10L6_CIGALE)
347-354 F8.6 [cm-2] e_logL6CIGALE Monochromatic luminosity at rest-frame 6um
(L6um) error (Log10L6CIGALEerr)
356-362 F7.5 --- Gamma Photon index (Γ) from Liu et al.
(2022A&A...661A...5L 2022A&A...661A...5L, Cat. J/A+A/661/A5)
(Photon_index)
364 A1 --- HardDetect [Y/N] Hard X-ray detection result
(Y=yes, N=no) (Hard_Detection)
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Note (1): MIR classification as follows:
0 = unclassified DOGs
1 = bump DOGs
2 = PL DOGs
Note (2): Optical classification as follows:
0 = normal
1 = BluDOG-like
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Acknowledgements:
Akatoki Noboriguchi, noboriguchi(at)astr.tohoku.ac.jp
(End) Patricia Vannier [CDS] 28-Apr-2025