J/A+A/708/A31 AGN optical-infrared relation (Ralowski+, 2026)
The optical-infrared relation for active galactic nuclei:
The role of contaminations.
Ralowski M., Hryniewicz K., Malek K., Pollo A., Risaliti G.
<Astron. Astrophys. 708, A31 (2026)>
=2026A&A...708A..31R 2026A&A...708A..31R (SIMBAD/NED BibCode)
ADC_Keywords: Active gal. nuclei ; QSOs ; Redshifts ; Photometry, SDSS ;
Photometry, infrared ; Ultraviolet
Keywords: galaxies: active - quasars: general - galaxies: statistics
Abstract:
Although the population of quasars evolved significantly in the past,
the properties of quasars as physical objects are supposed to remain
almost unchanged, which makes quasars promising candidates for
cosmological tests. The X-UV luminosity relation in particular is
widely used for this purpose. However, the potential of other spectral
domains for this purpose remains open.
The aim of the analysis we present is to test the parameter space in
order to build a well behaving OPT-IR correlation that could serve as
a cosmological probe. The main objective is to calibrate the OPT-IR
luminosity relation for quasars, focusing on accurate estimations of
dusty torus and accretion disk luminosities. We analyzed
contaminations related to host galaxies, particularly from polar dust,
the interstellar medium, and stellar emission that affect the optical
and infrared.
We used a sample of nearly 400 quasars with photometrical observations
and spectroscopical redshift divided into four redshift bins
(0.7-2.4). Full spectral energy distribution (SED) fitting was
performed with the CIGALE code, and results were compared with
simplified photometric luminosity estimates. The impact of non-active
galactic nucleus components and the role of polar dust in the fitting
process were assessed.
We show that for sources with a disk luminosity above 1045[erg/s],
the photometric estimates are consistent with SED-based values. While
polar dust contributes marginally to luminosity, its presence
significantly alters SED fitting, particularly the torus opening angle
and cold dust properties. In the optical domain, stellar emission is
the dominant contamination. In the infrared, disk emission and cold
dust play major roles. We propose two empirical calibrations for the
OPT-IR relation. We conclude that the optical band is dominated by the
accretion disk component above 1045 or 1046[erg/s] depending on
redshift, while IR luminosity is dominated by the dusty torus emission
above 1.6x1045 or 2x1046[erg/s] depending on the redshift. In this
high-luminosity regime, simplified photometric methods yield reliable
disk and torus luminosity estimates.
Description:
All fluxes are in mJy, in observer frame, AB system. All fluxes are
reduced for the extinction using Schlegel et al. 1998 reddening maps
and Cardelli et al. 1989 extinction law. Each flux (X) has an
observational error in the following column (X_err). If the
observation was not available for the given objects the value is set
to NaN. If the observation was available, but the its error was not
(which represent the detection limit) the flux error value is set to
negative. Such observations were used as upper limits in SED fitting
with CIGALE. SDSS observations are from the SDSS DR16Q catalogue (Like
et al. 2020ApJS..250....8L 2020ApJS..250....8L, Cat. VII/289). Each filter corresponds to
ugriz system. The converted from the nanomaggies (using the procedure
described in SDSS documentation, with additional conversion for u and z
filters to AB system (see SDSS AB conversion). WISE observations from
the all-WISE catalog (Wright et al. 2010AJ....140.1868W 2010AJ....140.1868W). The 'WISE4'
filter was corrected for so-called redleak (following Brown et al.
2014). UKIDSS survey data are from Lawrence et al.
2007MNRAS.379.1599L 2007MNRAS.379.1599L. Herschel observations are from: mid/far infrared
data from SPIRE (Griffin et al. 2010A&A...518L...3G 2010A&A...518L...3G) and PACS
(Poglitsch et al. 2010A&A...518L...2P 2010A&A...518L...2P) instruments.
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
sample.dat 858 348 Data sample
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See also:
II/314 : UKIDSS-DR8 LAS, GCS and DXS Surveys (Lawrence+, 2012)
VII/289 : SDSS quasar catalog, sixteenth data release (DR16Q) (Lyke+, 2020)
Byte-by-byte Description of file: sample.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
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1- 18 A18 --- SDSS The unique id for each galaxy from the
SDSS DR16Q, HHMMSS.ss_DDMMSS.s (1)
20- 40 F21.17 deg RAdeg Right ascension (J2000)
42- 63 F22.18 deg DEdeg Declination (J2000)
65- 82 F18.16 --- z Best spectroscopic redshift (2)
84-103 E20.16 mJy FNUV ? GALEX near-UV flux from GR6+/GR7 data
release (Martin et al., 2005, Cat. II/335)
105-122 E18.16 mJy e_FNUV ? Uncertainty on GALEX near-UV flux
124-141 F18.16 mJy Fup SDSS u-band flux
143-160 E18.16 mJy e_Fup Uncertainty on SDSS u-band flux
162-179 F18.16 mJy Fgp SDSS g-band flux
181-198 E18.12 mJy e_Fgp Uncertainty on SDSS g-band flux
200-217 F18.16 mJy Frp SDSS r-band flux
219-236 E18.16 mJy e_Frp Uncertainty on SDSS r-band flux
238-255 F18.16 mJy Fip SDSS i-band flux
257-274 E18.16 mJy e_Fip Uncertainty on SDSS i-band flux
276-293 F18.16 mJy Fzp SDSS z-band flux
295-312 F18.16 mJy e_Fzp Uncertainty on SDSS z-band flux
314-331 F18.16 mJy FWFCAMY UKIDSS Y-band flux
333-350 F18.16 mJy e_FWFCAMY Uncertainty on UKIDSS Y-band flux
352-369 F18.16 mJy FJ UKIDSS J-band flux
371-390 F20.16 mJy e_FJ ?=-99 Uncertainty on UKIDSS J-band flux
392-409 F18.16 mJy FH UKIDSS H-band flux
411-428 F18.16 mJy e_FH Uncertainty on UKIDSS H-band flux
430-447 F18.16 mJy FK UKIDSS K-band flux
449-466 F18.16 mJy e_FK Uncertainty on UKIDSS K-band flux
468-485 F18.16 mJy FWISE1 WISE W1 flux
487-504 F18.16 mJy e_FWISE1 Uncertainty on WISE W1 flux
506-523 F18.16 mJy FWISE2 WISE W2 flux
525-544 F20.16 mJy e_FWISE2 ?=-99 Uncertainty on WISE W2 flux
546-564 F19.16 mJy FWISE3 WISE W3 flux
566-585 F20.16 mJy e_FWISE3 ?=-99 Uncertainty on WISE W3 flux
587-605 F19.16 mJy FWISE4 WISE W4 flux (red-leak corrected)
607-626 F20.16 mJy e_FWISE4 ?=-99 Uncertainty on WISE W4 flux
628-646 F19.15 mJy FPSW Herschel SPIRE PSW flux
648-665 F18.15 mJy e_FPSW Uncertainty on SPIRE PSW flux
667-685 F19.15 mJy FPMW ? Herschel SPIRE PMW flux
687-704 F18.15 mJy e_FPMW ? Uncertainty on SPIRE PMW flux
706-724 F19.15 mJy FPLW ? Herschel SPIRE PLW flux
726-743 F18.15 mJy e_FPLW ? Uncertainty on SPIRE PLW flux
745-762 F18.15 mJy FPACSgreen ? Herschel PACS green flux
764-782 F19.16 mJy e_FPACSgreen ? Uncertainty on PACS green flux
784-801 F18.14 mJy FPACSred ? Herschel PACS red flux
803-820 F18.15 mJy e_FPACSred ? Uncertainty on PACS red flux
822-838 F17.14 mJy FPACSblue ? Herschel PACS blue flux
840-856 F17.15 mJy e_FPACSblue ? Uncertainty on PACS blue flux
858 I1 --- Lum-cut ? Selection flag (3)
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Note (1): Like et al. 2020ApJS..250....8L 2020ApJS..250....8L,
https://dat a.sdss.org/datamodel/files/BOSS_QSO/DR16Q /DR16Q_v4.html.
Note (2): from the SDSS DR16Q pipeline (Dawson et al. 2016AJ....151...44D 2016AJ....151...44D).
'Z' column in the SDSS DR16Q dataset.
Note (3): 1 = object above luminosity threshold based on the AGN disk luminosity
from the SKIRTOR model (L_disk > 10^(45+0.25*z) erg/s)
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Acknowledgements:
From Mateusz Ralowski, mateusz.ralowski(at)gmail.com
MR has been supported by the Polish National Agency for Academic
Exchange (Bekker grant BPN/BEK/2024/1/00298). This research was
supported by the Polish National Science Center grants
2018/30/M/ST9/00757 and 2023/50/A/ST9/00579 and by Polish Ministry of
Science and Higher Education grant DIR/WK/2018/12. This research was
funded by the Priority Research Area Digiworld under the program
Excellence Initiative - Research University at the Jagiellonian
University in Krakow. We gratefully acknowledge Polish
high-performance computing infrastructure PLGrid (HPC Center: ACK
Cyfronet AGH) for providing computer facilities and support within
computational grant no. PLG/2024/017491. This article is based upon
work from COST Action CA21136 - "Addressing observational tensions
in cosmology with systematics and fundamental physics (CosmoVerse)",
supported by COST (European Cooperation in Science and Technology).
This research has made use of the NASA/IPAC Infrared Science Archive,
which is funded by the National Aeronautics and Space Administration
and operated by the California Institute of Technology. Herschel
is an ESA space observatory with science instruments provided by
European-led Principal Investigator consortia and with important
participation from NASA.
References:
https://www.sdss.org/dr16/algorithms/magnitudes/
#Fluxunits:maggies and nanomaggies) : SDSS documentation
https://www.sdss.org/dr12/algorithms/fluxcal/#SDSStoAB : SDSS AB conversion
Lyke et al, 2020ApJS..250....8L 2020ApJS..250....8L : SDSS DR16Q catalogue
Wright et al., 2010AJ....140.1868W 2010AJ....140.1868W : all-WISE catalog
LykE et al., 2007MNRAS.379.1599L 2007MNRAS.379.1599L : UKIDSS survey
Griffin et al., 2010A&A...518L...3G 2010A&A...518L...3G : Herschel SPIRE instrument
Poglitsch et al., 2010A&A...518L...2P 2010A&A...518L...2P : Herschel PACS instrument
(End) Patricia Vannier [CDS] 04-Mar-2026