J/ApJ/960/15 AGN multiwavelength SED in POX 52 (Kawamuro+, 2024)
Coevolution and nuclear structure in the dwarf galaxy POX 52 studied by
multiwavelength data from radio to X-Ray.
Kawamuro T., Ricci C., Yamada S., Noda H., Li R., Temple M.J., Tortosa A.
<Astrophys. J., 960, 15 (2024)>
=2024ApJ...960...15K 2024ApJ...960...15K
ADC_Keywords: Active gal. nuclei; Energy distributions; X-ray sources;
Photometry, infrared; Black holes; Optical; Ultraviolet
Keywords: Astrophysical black holes ; X-ray active galactic nuclei ;
Active galactic nuclei ; AGN host galaxies ; Galaxy evolution ;
Intermediate-mass black holes
Abstract:
The nearby dwarf galaxy POX 52 at z=0.021 hosts an active galactic
nucleus (AGN) with a black hole (BH) mass of MBH∼105-6M☉ and
an Eddington ratio of ∼0.1-1. This object provides the rare
opportunity to study both AGN and host-galaxy properties in a low-mass
highly accreting system. To do so, we collected its multiwavelength
data from X-ray to radio. First, we construct a spectral energy
distribution, and by fitting it with AGN and host-galaxy components,
we constrain AGN-disk and dust-torus components. Then, while
considering the AGN-disk emission, we decompose optical Hubble Space
Telescope images. As a result, it is found that a classical bulge
component is probably present, and its mass (Mbulge) is consistent
with an expected value from a local relation. Lastly, we analyze new
quasi-simultaneous X-ray (0.2-30keV) data obtained by the Nuclear
Spectroscopic Telescope Array and XMM-Newton. The X-ray spectrum can
be reproduced by multicolor blackbody, warm and hot coronae, and disk
and torus reflection components. Based on this, the spin is estimated
to be aspin=0.998-0.814, which could suggest that most of the
current BH mass was achieved by prolonged mass accretion. Given the
presence of the bulge, POX 52 would have undergone a galaxy merger,
while the MBH-Mbulge relation and the inferred prolonged accretion
could suggest that AGN feedback occurred. Regarding the AGN structure,
the spectral slope of the hot corona, its relative strength to the
bolometric emission, and the torus structure are found to be
consistent with Eddington-ratio dependencies found for nearby AGNs.
Description:
Using XMM-Newton Optical Monitor (OM), Metal Oxide Semi-conductor
(MOS) and PN, we obtained X-ray, optical, and UV data (ID=0890430101)
of the nearby dwarf galaxy POX 52 with an exposure of ∼20ks between
2021-Dec-30 and 31.
The Optical Monitor (OM) on board XMM-Newton obtained data in the
Image+Fast mode from optical to UV using all the available filters (V,
B, U, UVW1, UVM2, and UVW2). See Sections 2.1.1 and 2.3.
We used the GALEX GR6/7 Data Release (STScI 2013; doi:10.17909/T9H59D;
see II/335) to cover the far-UV (FUV; 1516Å) and near-UV (NUV;
2267Å) bands), which was used also by Thornton+ (2008ApJ...686..892T 2008ApJ...686..892T).
See Section 2.1.2.
We utilized PanSTARRS data to add optical flux densities to our SED.
We adopted the Mean-object catalog, released in the PS1 DR2 (STScI
2022, doi: 10.17909/S0ZG-JX37; see II/389).
See Section 2.1.3.
To cover the near-IR band, we used the photometry data of the 2MASS
All-Sky Point Source Catalog (see II/246) in the same manner as
Thornton+ (2008). See Section 2.1.4.
In the IR band, we used WISE photometric data in the four bands:
3.4um, 4.6um, 12um, and 22um (W1, W2, W3, and W4, respectively).
POX_52 was detected in all bands in the AllWISE Source Catalog
(see II/328), and its WISE data were used in a low-mass AGN study by
Marleau+ (2017, J/A+A/602/A28). See Section 2.1.5.
To put stronger constraints on the emission in the IR band, we also
used Spitzer InfraRed Spectrograph (IRS) spectral data provided by the
Combined Atlas of Sources with Spitzer IRS Spectra catalog
(Lebouteiller+ 2011ApJS..196....8L 2011ApJS..196....8L, 2015ApJS..218...21L 2015ApJS..218...21L). The spectrum
was investigated by Hood+ (2017ApJ...838...26H 2017ApJ...838...26H). See Section 2.1.6.
Very Large Array (VLA) data in the S and C bands are available. The
S-band (∼3GHz) data were taken in the course of the VLA sky survey
(VLASS; Gordon+ 2020, 2021, J/ApJS/255/30). The survey data were
already analyzed by a VLASS team, and reconstructed images are
available on the VLASS website. See Section 2.1.7.
POX 52 was observed with the HST Advanced Camera for Surveys (ACS) and
the High Resolution Channel (HRC) on 2004 November 19 and 18. Two
optical filters of F435W and F814W were adopted in the respective
days, and the data were analyzed by Thornton+ (2008) in the past. We
used the data stored in the archive of Mikulski Archive for Space
Telescopes (the data are available at MAST:10.17909/J2EW-NH46).
See Section 2.2.
NuSTAR observed the target for ∼80ks quasi-simultaneously with
XMM-Newton (ID=60701047002). The NuSTAR observation started around 5ks
later than the XMM-Newton one. See Section 2.4.
Objects:
----------------------------------------------------------
RA (ICRS) DE Designation(s)
----------------------------------------------------------
12 02 56.93 -20 56 02.9 POX 52 = LEDA 38055
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File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table4.dat 62 441 Data of the AGN SED and spectral components
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See also:
B/xmm : XMM-Newton Observation Log (XMM-Newton Science Operation Center, 2012-)
B/hst : HST Archived Exposures Catalog (STScI, 2007)
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
VIII/76 : Leiden/Argentine/Bonn (LAB) Survey of Galactic HI (Kalberla+ 2005)
II/311 : WISE All-Sky Data Release (Cutri+ 2012)
II/328 : AllWISE Data Release (Cutri+ 2013)
II/335 : Revised cat. of GALEX UV sources (GUVcat_AIS GR6+7) (Bianchi+ 2017)
II/389 : The Pan-STARRS release 1 (PS1) Survey - DR2 (Magnier+, 2025)
J/ApJ/670/92 : New sample of low-mass black holes in AGN (Greene+, 2007)
J/ApJS/177/148 : HST survey of 3CR counterparts. II. (Floyd+, 2008)
J/A+A/495/421 : Cat. of AGN in XMM-Newton archive (CAIXA) (Bianchi+, 2009)
J/ApJS/206/4 : SED & bolometric corr. for luminous QSOs (Krawczyk+, 2013)
J/ApJS/210/3 : SDSS bulge, disk and total stellar masses (Mendel+, 2014)
J/MNRAS/454/766 : Mid-infrared-X-ray correlation for local AGNs (Asmus+, 2015)
J/MNRAS/446/3943 : galaxies 2D phot. decompositions in SDSS-DR7 (Meert+, 2015)
J/A+A/588/A70 : Hard X-ray view of the soft excess in AGN (Boissay+, 2016)
J/ApJ/835/74 : IR phot. of AGNs in Swift/BAT 70-month (Ichikawa+, 2017)
J/A+A/602/A28 : IR signature of CMBH in nearby dwarf gal. (Marleau+, 2017)
J/ApJS/233/17 : Swift/BAT AGN spectroscopic survey. V. X-ray (Ricci+, 2017)
J/ApJ/836/185 : SEDs of radio continuum from KINGFISHER (Tabatabaei+, 2017)
J/ApJ/896/10 : NSA low-mass gal. with PTF obs. (Baldassare+, 2020)
J/A+A/654/A93 : Polar dust obscuration in broad-line AGN (Buat+, 2021)
J/ApJS/255/30 : VLASS QL Ep.1 Catalog, CIRADA version (Gordon+, 2021)
J/ApJ/912/91 : A value-added cat. for SDSS DR16 QSOs at z<0.7 (Toba+, 2021)
J/ApJS/262/54 : The CGS. X. Stellar mass parameters for bulges (Gao+, 2022)
J/ApJS/261/8 : BASS. XXIX. NIR view of broad-line regions (Ricci+, 2022)
J/ApJS/259/37 : IDEOS. II. The 5.4-36µm range (Spoon+, 2022)
J/ApJS/265/37 : Multiwavelength SED analysis of GOALS ULIRGs (Yamada+, 2023)
Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 8 E8.2 Hz Freq [4.43e+11/1.71e+21] Frequency
10- 17 E8.2 10-7W TLum [1e+35/8.9e+42] Total luminosity (1)
19- 26 E8.2 10-7W ADLum [1.29e+35/8.69e+42]? Accretion disk luminosity
(1)
28- 35 E8.2 10-7W IRLum [1.47e+35/6.38e+40]? IR torus luminosity (1)
37- 44 E8.2 10-7W XPLLum [1e+35/3.15e+41]? X-ray power-law luminosity (1)
46- 53 E8.2 10-7W XDRLum [1.96e+38/8.87e+41]? X-ray disk reflection
luminosity (1)
55- 62 E8.2 10-7W XTLum [4.21e+35/1.5e+41]? X-ray torus luminosity (1)
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Note (1): In units of erg/s. Luminosities below 1e+35 erg/s are blank.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 30-Jan-2026