We conduct hard X-ray to radio multiwavelength spectral energy distribution (SED) decomposition for 57 local luminous and ultraluminous infrared galaxies observed with the Nuclear Spectroscopic Telescope Array and/or Swift/Burst Alert Telescope in the GOALS sample. We modify the latest SED-fitting code X-CIGALE by implementing the infrared (IR) CLUMPY model, allowing us to conduct the multiwavelength study with the X-ray torus model XCLUMPY self-consistently. Adopting the torus parameters obtained by the X-ray fitting, we estimate the properties of the host galaxies, active galactic nucleus (AGN) tori, and polar dust. The star formation rates (SFRs) become larger with merger stage and most of them are above the main sequence. The SFRs are correlated with radio luminosity, indicating starburst emission is dominant in the radio band. Although polar-dust extinction is much smaller than torus extinction, the UV-to-IR (mainly IR) polar dust luminosities are ∼2 times larger than the torus ones. The polar-dust temperature decreases while the physical size, estimated by the temperature and dust sublimation radius, increases with AGN luminosity from a few tens of parsec (early mergers) to kiloparsec scales (late mergers), where the polar dust likely comes from expanding (i.e., evolving) dusty outflows. A comparison between the SFRs and intrinsic AGN luminosities suggests that starbursts occur first and AGNs arise later, and overall their growth rates follow the simultaneous coevolution local galaxy–SMBH mass relation. We confirm the coexistence of intense starbursts, AGNs, and large-scale outflows in late mergers, supporting a standard AGN feedback scenario.

https://iopscience.iop.org/article/10.3847/1538-4365/acb349/pdf

Hard X-Ray to Radio Multiwavelength SED Analysis of Local U/LIRGs in the GOALS Sample with a Self-consistent AGN Model including a Polar-dust Component

A fundamental goal of modern-day astrophysics is to understand the connection between supermassive black hole (SMBH) growth and galaxy evolution. Merging galaxies offer one of the most dramatic channels for galaxy evolution known, capable of driving inflows of gas into galactic nuclei, potentially fueling both star formation and central SMBH activity. Dual active galactic nuclei (dual AGNs) in late-stage mergers with nuclear pair separations <10 kpc are thus ideal candidates to study SMBH growth along the merger sequence since they coincide with the most transformative period for galaxies. However, dual AGNs can be extremely difficult to confirm and study. Hard X-ray (>10 keV) studies offer a relatively contamination-free tool for probing the dense obscuring environments predicted to surround the majority of dual AGN in late-stage mergers. To date, only a handful of the brightest and closest systems have been studied at these energies due to the demanding instrumental requirements involved. We demonstrate the unique capabilities of HEX-P to spatially resolve the soft and - for the first time - hard X-ray counterparts of closely-separated (∼2″−5″) dual AGNs in the local Universe. By incorporating physically-motivated obscuration models, we reproduce realistic broadband X-ray spectra expected for deeply embedded accreting SMBHs. Hard X-ray spatially resolved observations of dual AGNs—accessible only to HEX-P—will hence transform our understanding of dual AGN in the nearby Universe.

The high energy X-ray probe (HEX-P): the future of hard X-ray dual AGN science

Abstract Mergers of galaxies are a ubiquitous phenomenon in the universe and represent a natural consequence of the “bottom-up” mass accumulation and galaxy evolution cosmological paradigm. It is generally accepted that the peak of active galactic nucleus (AGN) accretion activity occurs at nuclear separations of ≲10 kpc for major mergers. Here we present new NuSTAR and XMM-Newton observations for a subsample of mid-IR preselected dual AGN candidates in an effort to better constrain the column densities along the line of sight (LOS) for each system. Only one dual AGN candidate, J0841+0101, is detected as a single, unresolved source in the XMM-Newton and NuSTAR imaging, while the remaining three dual AGN candidates, J0122+0100, J1221+1137, and J1306+0735, are not detected with NuSTAR; if these nondetections are due to obscuration alone, these systems are consistent with being absorbed by column densities of log( N H /cm −2 ) ≥ 24.9, 24.6, and 24.3, which are roughly consistent with previously inferred column densities in these merging systems. In the case of J0841+0101, the analysis of the 0.3–30 keV spectra reveal an LOS column density of N H ≳ 10 24 cm −2 , significantly larger than the column densities previously reported for this system and demonstrating the importance of the higher signal-to-noise ratio XMM-Newton spectra and access to the &gt;10 keV energies via NuSTAR. Though it is unclear if J0841+0101 truly hosts a dual AGN, these results are in agreement with the high obscuring columns expected in AGNs in late-stage mergers. 

NuSTAR Observations of Four Mid-IR–Selected Dual AGN Candidates in Galaxy Mergers


               <jats:p>We study “buried” active galactic nuclei (AGNs) almost fully covered by circumnuclear material in ultra/luminous infrared galaxies (U/LIRGs), which show weak ionized lines from narrow-line regions. Employing an indicator of a [O <jats:sc>iv</jats:sc>] 25.89 or [Ne <jats:sc>v</jats:sc>] 14.32 <jats:italic>μ</jats:italic>m line to 12 <jats:italic>μ</jats:italic>m AGN luminosity ratio, we find 17 buried AGN candidates that are [O <jats:sc>iv</jats:sc>]-weak (<jats:italic>L</jats:italic>
                  <jats:sub>[O <jats:sc>IV</jats:sc>]</jats:sub>/<jats:italic>L</jats:italic>
                  <jats:sub>12,AGN</jats:sub> ≤ −3.0) or [Ne <jats:sc>v</jats:sc>]-weak (<jats:italic>L</jats:italic>
                  <jats:sub>[Ne V]</jats:sub>/<jats:italic>L</jats:italic>
                  <jats:sub>12,AGN</jats:sub> ≤ −3.4) among 30 AGNs in local U/LIRGs. For the [O <jats:sc>iv</jats:sc>]-weak AGNs, we estimate their covering fractions of Compton-thick (CT; <jats:italic>N</jats:italic>
                  <jats:sub>H</jats:sub> ≥ 10<jats:sup>24</jats:sup> cm<jats:sup>−2</jats:sup>) material with an X-ray clumpy torus model to be <jats:inline-formula>
                     <jats:tex-math>
<?CDATA ${f}_{\mathrm{CT}}^{(\mathrm{spec})}=0.55\pm 0.19$?>
</jats:tex-math>
                     <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                        <mml:msubsup>
                           <mml:mrow>
                              <mml:mi>f</mml:mi>
                           </mml:mrow>
                           <mml:mrow>
                              <mml:mi>CT</mml:mi>
                           </mml:mrow>
                           <mml:mrow>
                              <mml:mo stretchy="false">(</mml:mo>
                              <mml:mi>spec</mml:mi>
                              <mml:mo stretchy="false">)</mml:mo>
                           </mml:mrow>
                        </mml:msubsup>
                        <mml:mo>=</mml:mo>
                        <mml:mn>0.55</mml:mn>
                        <mml:mo>±</mml:mo>
                        <mml:mn>0.19</mml:mn>
                     </mml:math>
                     <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjad2936ieqn1.gif" xlink:type="simple" />
                  </jats:inline-formula> on average. This value is consistent with the fraction of CT AGNs (<jats:inline-formula>
                     <jats:tex-math>
<?CDATA ${f}_{\mathrm{CT}}^{(\mathrm{stat})}=53 \% \pm 12 \% $?>
</jats:tex-math>
                     <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                        <mml:msubsup>
                           <mml:mrow>
                              <mml:mi>f</mml:mi>
                           </mml:mrow>
                           <mml:mrow>
                              <mml:mi>CT</mml:mi>
                           </mml:mrow>
                           <mml:mrow>
                              <mml:mo stretchy="false">(</mml:mo>
                              <mml:mi>stat</mml:mi>
                              <mml:mo stretchy="false">)</mml:mo>
                           </mml:mrow>
                        </mml:msubsup>
                        <mml:mo>=</mml:mo>
                        <mml:mn>53</mml:mn>
                        <mml:mo>%</mml:mo>
                        <mml:mo>±</mml:mo>
                        <mml:mn>12</mml:mn>
                        <mml:mo>%</mml:mo>
                     </mml:math>
                     <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjad2936ieqn2.gif" xlink:type="simple" />
                  </jats:inline-formula>) among the [O <jats:sc>iv</jats:sc>]-weak AGNs in U/LIRGs and much larger than that in Swift/Burst Alert Telescope (BAT) AGNs (23% ± 6%). The fraction of [O <jats:sc>iv</jats:sc>]-weak AGNs increases from <jats:inline-formula>
                     <jats:tex-math>
<?CDATA ${27}_{-10}^{+13} \% $?>
</jats:tex-math>
                     <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                        <mml:msubsup>
                           <mml:mrow>
                              <mml:mn>27</mml:mn>
                           </mml:mrow>
                           <mml:mrow>
                              <mml:mo>−</mml:mo>
                              <mml:mn>10</mml:mn>
                           </mml:mrow>
                           <mml:mrow>
                              <mml:mo>+</mml:mo>
                              <mml:mn>13</mml:mn>
                           </mml:mrow>
                        </mml:msubsup>
                        <mml:mo>%</mml:mo>
                     </mml:math>
                     <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjad2936ieqn3.gif" xlink:type="simple" />
                  </jats:inline-formula> (early) to <jats:inline-formula>
                     <jats:tex-math>
<?CDATA ${66}_{-12}^{+10} \% $?>
</jats:tex-math>
                     <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                        <mml:msubsup>
                           <mml:mrow>
                              <mml:mn>66</mml:mn>
                           </mml:mrow>
                           <mml:mrow>
                              <mml:mo>−</mml:mo>
                              <mml:mn>12</mml:mn>
                           </mml:mrow>
                           <mml:mrow>
                              <mml:mo>+</mml:mo>
                              <mml:mn>10</mml:mn>
                           </mml:mrow>
                        </mml:msubsup>
                        <mml:mo>%</mml:mo>
                     </mml:math>
                     <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjad2936ieqn4.gif" xlink:type="simple" />
                  </jats:inline-formula> (late mergers). Similar results are obtained with the [Ne <jats:sc>v</jats:sc>] line. The [O <jats:sc>iv</jats:sc>]- or [Ne <jats:sc>v</jats:sc>]-weak AGNs in late mergers show larger <jats:italic>N</jats:italic>
                  <jats:sub>H</jats:sub> and Eddington ratios (<jats:italic>λ</jats:italic>
                  <jats:sub>Edd</jats:sub>) than those of the Swift/BAT AGNs, and the largest <jats:italic>N</jats:italic>
                  <jats:sub>H</jats:sub> is ≳10<jats:sup>25</jats:sup> cm<jats:sup>−2</jats:sup> at <jats:inline-formula>
                     <jats:tex-math>
<?CDATA $\mathrm{log}{\lambda }_{\mathrm{Edd}}\sim -1$?>
</jats:tex-math>
                     <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                        <mml:mi>log</mml:mi>
                        <mml:msub>
                           <mml:mrow>
                              <mml:mi>λ</mml:mi>
                           </mml:mrow>
                           <mml:mrow>
                              <mml:mi>Edd</mml:mi>
                           </mml:mrow>
                        </mml:msub>
                        <mml:mo>∼</mml:mo>
                        <mml:mo>−</mml:mo>
                        <mml:mn>1</mml:mn>
                     </mml:math>
                     <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjad2936ieqn5.gif" xlink:type="simple" />
                  </jats:inline-formula>, close to the effective Eddington limit for CT material. These suggest that (1) the circumnuclear material in buried AGNs is regulated by the radiation force from high-<jats:italic>λ</jats:italic>
                  <jats:sub>Edd</jats:sub> AGNs on the CT obscurers, and (2) their dense material with large <jats:inline-formula>
                     <jats:tex-math>
<?CDATA ${f}_{\mathrm{CT}}^{(\mathrm{spec})}$?>
</jats:tex-math>
                     <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                        <mml:msubsup>
                           <mml:mrow>
                              <mml:mi>f</mml:mi>
                           </mml:mrow>
                           <mml:mrow>
                              <mml:mi>CT</mml:mi>
                           </mml:mrow>
                           <mml:mrow>
                              <mml:mo stretchy="false">(</mml:mo>
                              <mml:mi>spec</mml:mi>
                              <mml:mo stretchy="false">)</mml:mo>
                           </mml:mrow>
                        </mml:msubsup>
                     </mml:math>
                     <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjad2936ieqn6.gif" xlink:type="simple" />
                  </jats:inline-formula> (∼0.5 ± 0.1) in U/LIRGs is a likely cause of a unique structure of buried AGNs, whose amount of material may be maintained through merger-induced supply from their host galaxies.</jats:p>

[O iv]- and [Ne v]-weak Active Galactic Nuclei Hidden by Compton-thick Material in Late Mergers

Abstract Above ∼3 keV, the X-ray spectrum of active galactic nuclei (AGNs) is characterized by the intrinsic continuum and Compton reflection features. For type-1 AGNs, several regions may contribute to the reflection. To investigate the nature of the reflecting medium, we perform a systematic analysis of the reflector using XMM-Newton and Nuclear Spectroscopic Telescope Array observations of a sample of 22 type-1 AGNs. We create a baseline model that includes Galactic absorption and an intrinsically absorbed power law, plus a reflection model. We test a set of nine reflection models in a subsample of five objects. Based on these results, we select three models to be tested on the entire sample, accounting for distinct physical scenarios: neutral/distant reflection, ionized/relativistic reflection, and neutral/distant+ionized/relativistic reflection, namely, a hybrid model. We find that 18 sources require the reflection component to fit their spectra. Among them, 67% prefer the hybrid model. Neutral and ionized models are equally preferred by three sources. We conclude that both the neutral/distant reflector most probably associated with the inner edges of the torus and the ionized/relativistic reflector associated with the accretion disk are required to describe the reflection in type-1 AGNs. 

Testing Physical Scenarios for the Reflection Features of Type-1 AGNs using XMM-Newton and NuSTAR Simultaneous Observations

We present the result of a broadband (0.5–70 keV) X-ray spectral analysis of the late-merger galaxy Mrk 739, which contains a dual active galactic nucleus (AGN), Mrk 739E and Mrk 739W, with a separation of ≈3.4 kpc. The spectra obtained with NuSTAR, Chandra, XMM-Newton, and Swift/BAT are simultaneously analyzed by separating the contributions from the two AGNs and extended emission with the Chandra data. To evaluate the reflection components from the AGN tori, we consider two models, a phenomenological one (pexrav and zgauss) and a more physically motivated one (XCLUMPY). On the basis of the results with XCLUMPY, we find that the AGNs in Mrk 739E and Mrk 739W have intrinsic 2–10 keV luminosities of 1.0 × 1043 and 7.5 × 1041 erg s−1 absorbed by hydrogen column densities of N H < 6.5 × 1019 cm−2 and NH=6.9−1.7+3.2×1021cm−2 , respectively. The torus-covering fraction of the material with N H > 1022cm−2 in Mrk 739E, CT(22)<0.50 at a 90% confidence limit, is found to be smaller than those found for late-merger ultra/luminous infrared galaxies, CT(22)=0.71±0.16 (mean and standard deviation). Considering the small star formation rate of Mrk 739E, we suggest that the gas-to-mass ratio of the host galaxy is an important parameter to determine the circumnuclear environment of an AGN in a late merger.

https://iopscience.iop.org/article/10.3847/1538-4357/ac97ec/pdf

Broadband X-Ray Spectral Analysis of the Dual AGN System Mrk 739


 Radio galaxies are a key population to understand the importance of relativistic jets in active galactic nucleus (AGN) feedback. We present the results of a systematic, broad-band X-ray spectral analysis of hard X-ray selected radio galaxies to investigate their nuclear structures. In this study, we focus on the seven most radio-loud, X-ray obscured narrow-line radio galaxies in the Swift/BAT 70 month AGN catalogue. The spectra from 0.5 keV up to 66 keV obtained with Suzaku and NuSTAR of six objects are newly analysed here by utilizing the X-ray clumpy torus model (xclumpy), whereas we refer to the literature for the results of Centaurus A. We find that these radio galaxies have similar torus covering fractions compared with radio-quiet AGNs at the same Eddington ratios (−3 < log λEdd < −1). This result implies that (1) the torus structure is not an important factor that determines the presence of jets and (2) AGN jets have physically little effect on the torus.

/pdf/broad-band-x-ray-spectral-study-of-nuclear-structure-in-22o1zoc9.pdf

Broad-band X-ray spectral study of nuclear structure in local obscured radio galaxies

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

Koki Inaba

Author Tools

Chat about Author

Papers

Broadband X-Ray Spectral Analysis of the Dual AGN System Mrk 739

Broad-band X-ray spectral study of nuclear structure in local obscured radio galaxies