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We present one of the largest multiwavelength studies of simultaneous optical-to-X-ray spectral energy distributions (SEDs) of unobscured active galactic nuclei (AGN) in the local Universe. Using a representative sample of hard-X-ray-selected AGN from the 70-month Swift/BAT catalog, with optical/UV photometric data from Swift/UVOT and X-ray spectral data from Swift/XRT, we constructed broadband SEDs of 236 nearby AGN (0.001

We report the discovery of a hyperluminous type 1 quasar (eFEDS J082826.9-013911; eFEDSJ0828-0139) at $z_{\rm spec}$ = 1.622 with a super-Eddington ratio ($\lambda_{\rm Edd}$). We perform the optical spectroscopic observations with KOOLS-IFU on the Seimei Telescope. The black hole mass ($M_{\rm BH}$) based on the single-epoch method with MgII $\lambda$2798 is estimated to be $M_{\rm BH} = (6.2 \pm 1.2) \times 10^8$ $M_{\odot}$. To measure the precise infrared luminosity ($L_{\rm IR}$), we obtain submillimeter data taken by SCUBA-2 on JCMT and conduct the spectral energy distribution analysis with X-ray to submillimeter data. We find that $L_{\rm IR}$ of eFEDSJ0828-0139 is $L_{\rm IR} = (6.8 \pm 1.8) \times 10^{13}$ $L_{\odot}$, confirming the existence of a hypeluminous infrared galaxy (HyLIRG). $\lambda_{\rm Edd}$ is estimated to be $\lambda_{\rm Edd} = 3.6 \pm 0.7$, making it one of the quasars with the highest BH mass accretion rate at cosmic noon., Comment: 9 pages, 3 figures, and 3 tables, accepted for publication in PASJ

We present a study of the molecular gas in five closely-spaced ($R_{\perp}<20$ kpc) dual quasars ($L_{\rm bol}\gtrsim10^{44}~\mathrm{erg~s}^{-1}$) at redshifts $0.4

As an inaugural investigation under the X-ray Winds In Nearby-to-distant Galaxies (X-WING) program, we assembled a dataset comprising 132 active galactic nuclei (AGNs) spanning redshifts $z \sim 0$-$4$ characterized by blueshifted absorption lines indicative of X-ray winds. Through an exhaustive review of previous research, we compiled the outflow parameters for 573 X-ray winds, encompassing key attributes such as outflow velocities ($V_{\rm out}$), ionization parameters ($\xi$), and hydrogen column densities. By leveraging the parameters $V_{\rm out}$ and $\xi$, we systematically categorized the winds into three distinct groups: ultrafast outflows (UFOs), low-ionization parameter (low-IP) UFOs, and warm absorbers. Strikingly, a discernible absence of linear correlations in the outflow parameters, coupled with distributions approaching instrumental detection limits, was observed. Another notable finding was the identification of a velocity gap around $V_{\rm out} \sim 10,000~{\rm km~s^{-1}}$. This gap was particularly evident in the winds detected via absorption lines within the $\lesssim$2 keV band, indicating disparate origins for low-IP UFOs and warm absorbers. In cases involving Fe XXV/Fe XXVI lines, where the gap might be attributed to potential confusion between emission/absorption lines and the Fe K-edge, the possibility of UFOs and galactic-scale warm absorbers being disconnected is considered. An examination of the outflow and dust sublimation radii revealed a distinction: UFOs appear to consist of dust-free material, whereas warm absorbers likely comprise dusty gas. From 2024, the X-Ray Imaging and Spectroscopy Mission (XRISM) is poised to alleviate observational biases, providing insights into the authenticity of the identified gap, a pivotal question in comprehending AGN feedback from UFOs., Comment: 34 pages, 4 tables, 7 figures, accepted in ApJS. The CSV files of Tables B2-B4 are available from the URL: http://www.kusastro.kyoto-u.ac.jp/~styamada/yamada2024bApJS/XWING-PaperI_tables.zip

We investigated the gas obscuration and host galaxy properties of active galactic nuclei (AGN) during the peak of cosmic accretion growth of supermassive black holes (SMBHs) at redshift 0.8-1.8 using X-ray detected AGN with mid-infrared and far-infrared detection. The sample was classified as type-1 and type-2 AGN using optical spectral and morphological classification while the host galaxy properties were estimated with multiwavelength SED fitting. For type-1 AGN, the black hole mass was determined from MgII emission lines while the black hole mass of type-2 AGN was inferred from the host galaxy's stellar mass. Based on the derived parameters, the distribution of the sample in the absorption hydrogen column density ($N_{\rm H}$) vs. Eddington ratio diagram is examined. Among the type-2 AGN, $28\pm5$\% are in the forbidden zone, where the obscuration by dust torus cannot be maintained due to radiation pressure on dusty material. The fraction is higher than that observed in the local universe from the BAT AGN Spectroscopic Survey (BASS) data release 2 ($11\pm3$\%). The higher fraction implies that the obscuration of the majority of AGN is consistent with the radiation pressure regulated unified model but with an increased incidence of interstellar matter (ISM) obscured AGN. We discuss the possibility of dust-free absorption in type-1 AGN and heavy ISM absorption in type-2 AGN. We also find no statistical difference in the star-formation activity between type-1 and type-2 AGN which may suggest that obscuration triggered by a gas-rich merging is not common among X-ray detected AGN in this epoch., Comment: Accepted for publication in MNRAS

Herein, we present the statistical properties of active galactic nuclei (AGNs) for approximately 1 million member galaxies of galaxy groups and clusters, with 0.1 $<$ cluster redshift ($z_{\rm cl}$) $<$ 1.4, selected using Subaru Hyper Suprime-Cam, the so-called CAMIRA clusters. In this research, we focused on the AGN power fraction ($f_{\rm AGN}$), which is defined as the proportion of the contribution of AGNs to the total infrared (IR) luminosity, $L_{\rm IR}$ (AGN)/$L_{\rm IR}$, and examined how $f_{\rm AGN}$ depends on (i) $z_{\rm cl}$ and (ii) the distance from the cluster center. We compiled multiwavelength data using the ultraviolet--mid-IR range. Moreover, we performed spectral energy distribution fits to determine $f_{\rm AGN}$ using the CIGALE code with the SKIRTOR AGN model. We found that (i) the value of $f_{\rm AGN}$ in the CAMIRA clusters is positively correlated with $z_{\rm cl}$, with the correlation slope being steeper than that for field galaxies, and (ii) $f_{\rm AGN}$ exhibits a high value at the cluster outskirts. These results indicate that the emergence of AGN population depends on the redshift and environment and that galaxy groups and clusters at high redshifts are important in AGN evolution. Additionally, we demonstrated that cluster--cluster mergers may enhance AGN activity at the outskirts of particularly massive galaxy clusters. Our findings are consistent with a related study on the CAMIRA clusters that was based on the AGN number fraction., Comment: 25 pages, 24 figures, and 3 tables, accepted for publication in ApJ. A value-added CAMIRA member galaxy catalog and the best-fit SED for each member galaxy will be available as FITS or machine-readable tables

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 [O IV] 25.89-um or [Ne V] 14.32-um line to 12-um AGN luminosity ratio, we find 17 buried AGN candidates that are [O IV]-weak ($L_{\rm [O\,IV]}$/$L_{\rm 12,AGN} \leq -$3.0) or [Ne V]-weak ($L_{\rm [Ne\,V]}$/$L_{\rm 12,AGN} \leq -$3.4) among 30 AGNs in local U/LIRGs. For the [O IV]-weak AGNs, we estimate their covering fractions of Compton-thick (CT; $N_{\rm H} \geq 10^{24}$ cm$^{-2}$) material with an X-ray clumpy torus model to be $f^{\rm (spec)}_{\rm CT} = 0.55\pm0.19$ on average. This value is consistent with the fraction of CT AGNs ($f^{\rm (stat)}_{\rm CT} = 53\pm12$%) among the [O IV]-weak AGNs in U/LIRGs and much larger than that in Swift/BAT AGNs ($23\pm6$%). The fraction of [O IV]-weak AGNs increases from $27^{+13}_{-10}$% (early) to $66^{+10}_{-12}$% (late mergers). Similar results are obtained with the [Ne V] line. The [O IV] or [Ne V]-weak AGNs in late mergers show larger $N_{\rm H}$ and Eddington ratios ($\lambda_{\rm Edd}$) than those of the Swift/BAT AGNs, and the largest $N_{\rm H}$ is $\gtrsim$10$^{25}$ cm$^{-2}$ at ${\log}\lambda_{\rm Edd} \sim -$1, close to the effective Eddington limit for CT material. These suggest that (1) the circumnuclear material in buried AGNs is regulated by the radiation force from high-$\lambda_{\rm Edd}$ AGNs on the CT obscurers, and (2) their dense material with large $f^{\rm (spec)}_{\rm CT}$ ($\sim 0.5 \pm 0.1$) 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., Comment: 13 pages, 10 figures, and 1 table, accepted for publication in ApJ

Sub/millimeter galaxies are a key population for the study of galaxy evolution because the majority of star formation at high redshifts occurred in galaxies deeply embedded in dust. To search for this population, we have performed an extensive survey with ALMA, called the ALMA Lensing Cluster Survey (ALCS). This survey covers 133 arcmin^2 area and securely detects 180 sources at z~0.5-6 with a flux limit of ~0.2 mJy at 1.2 mm (Fujimoto et al. 2023). Here we report the results of multi-wavelength spectral energy distribution (SED) analysis of the whole ALCS sample, utilizing the observed-frame UV to millimeter photometry. We find that the majority of the ALCS sources lie on the star-forming main sequence, with a smaller fraction showing intense starburst activities. The ALCS sample contains high infrared-excess sources IRX=log(Ldust/LUV)>1), including two extremely dust-obscured galaxies (IRX>5). We also confirm that the ALCS sample probes a broader range in lower dust mass than conventional SMG samples in the same redshift range. We identify six heavily obscured AGN candidates that are not detected in the archival Chandra data in addition to the three X-ray AGNs reported by Uematsu et al. (2023). The inferred AGN luminosity density shows a possible excess at z=2-3 compared with that determined from X-ray surveys below 10 keV., Comment: 27 pages, 20 figures

We perform a systematic, multiwavelength spectral energy distribution (SED) analysis of X-ray detected Active Galactic Nuclei (AGNs) at $z=0.2-0.8$ with SDSS counterparts in the Stripe 82 region, consisting of 60 type-1 and 137 type-2 AGNs covering a 2--10 keV luminosity range of $41.6 < {\rm log}\ L_{\rm x} < 44.7$. The latest CIGALE code, where dusty polar components are included, is employed. To obtain reliable host and AGN parameters in type-1 AGNs, we utilize the image decomposed optical SED of host galaxies by Li et al. (2021) based on the Subaru Hyper Suprime-Cam (HSC) images. The mean ratio of black hole masses ($M_{\rm BH}$) and stellar masses ($M_{\rm stellar}$) of our X-ray detected type-1 AGN sample, $\log (M_{\rm BH}/M_{\rm stellar}) = -2.7\pm0.5$, is close to the local relation between black hole and stellar masses, as reported by Li et al. (2021) for SDSS quasars. This ratio is slightly lower than that found for more luminous ($\log L_{\rm bol} > 45$) type-1 AGNs at $z\sim1.5$. This can be explained by the AGN-luminosity dependence of $\log (M_{\rm BH}/M_{\rm stellar})$, which little evolves with redshift. We confirm the trend that the UV-to-X-ray slope ($\alpha_{\rm OX}$) or X-ray-to-bolometric correction factor ($\kappa_{2-10}$) increases with AGN luminosity or Eddington ratio. We find that type-1 and type-2 AGNs with the same luminosity ranges share similar host stellar-mass distributions, whereas type-2s tend to show smaller AGN luminosities than type-1s. This supports the luminosity (or Eddington ratio) dependent unified scheme., Comment: 22 pages, 9 figures, 7 tables, accepted for ApJ publication

We investigate the black hole mass function (BHMF) and Eddington ratio distribution function (ERDF) of broad-line AGNs at z=4, based on a sample of 52 quasars with i<23.2 at 3.50 < z < 4.25 from the Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP) S16A-Wide2 dataset, and 1,462 quasars with i<20.2 in the same redshift range from the Sloan Digital Sky Survey (SDSS) DR7 quasar catalog. Virial BH masses of quasars are estimated using the width of the CIV 1549{\AA} line and the continuum luminosity at 1350{\AA}. To obtain the intrinsic broad-line AGN BHMF and ERDF, we correct for the incompleteness in the low-mass and/or low-Eddington-ratio ranges caused by the flux-limited selection. The resulting BHMF is constrained down to $\log M_{\rm BH}/M_{\odot}\sim7.5$. In comparison with broad-line AGN BHMFs at z=2 in the literature, we find that the number density of massive SMBHs peaks at higher redshifts, consistent with the "down-sizing" evolutionary scenario. Additionally, the resulting ERDF shows a negative dependence on BH mass, suggesting more massive SMBHs tend to accrete at lower Eddington ratios at z=4. With the derived intrinsic broad-line AGN BHMF, we also evaluate the active fraction of broad-line AGNs among the entire SMBH population at z=4. The resulting active fraction may suggest a positive dependence on BH mass. Finally, we examine the time evolution of broad-line AGN BHMF between z=4 and 6 through solving the continuity equation. The results suggest that the broad-line AGN BHMFs at z=4-6 only show evolution in their normalization, but with no significant changes in their shape., Comment: 38 pages, 26 figures. Submitted to ApJ. Data is available in https://github.com/wanqqq31/BHMF_hsc_z4

We present a catalog of the millimeter-wave (mm-wave) continuum properties of 98 nearby ($z <$ 0.05) active galactic nuclei (AGNs) selected from the 70-month Swift/BAT hard X-ray catalog that have precisely determined X-ray spectral properties and subarcsec-resolution ALMA Band-6 (211--275 GHz) observations as of 2021 April. Due to the hard-X-ray ($>$ 10 keV) selection, the sample is nearly unbiased for obscured systems at least up to Compton-thick-level obscuration, and provides the largest number of AGNs with high physical resolution mm-wave data ($\lesssim$ 100--200 pc). Our catalog reports emission peak coordinates, spectral indices, and peak fluxes and luminosities at 1.3 mm (230 GHz). Additionally, high-resolution mm-wave images are provided. Using the images and creating radial surface brightness profiles of mm-wave emission, we identify emission extending from the central source and isolated blob-like emission. Flags indicating the presence of these emission features are tabulated. Among 90 AGNs with significant detections of nuclear emission, 37 AGNs ($\approx$ 41%) appear to have both or one of extended or blob-like components. We, in particular, investigate AGNs that show well-resolved mm-wave components and find that these seem to have a variety of origins (i.e., a jet, radio lobes, a secondary AGN, stellar clusters, a narrow line region, galaxy disk, active star-formation regions, and AGN-driven outflows), and some components have currently unclear origins., Comment: 49 pages, 7 figures, 3 tables, accepted for publication in ApJS

One of the key questions on active galactic nuclei (AGN) in galaxy clusters is how AGN could affect the formation and evolution of member galaxies and galaxy clusters in the history of the Universe. To address this issue, we investigate the dependence of AGN number fraction ($f_{\rm AGN}$) on cluster redshift ($z_{\rm cl}$) and distance from the cluster center ($R/R_{\rm 200}$). We focus on more than 27,000 galaxy groups and clusters at $0.1 < z_{\rm cl} < 1.4$ with more than 1 million member galaxies selected from the Subaru Hyper Suprime-Cam. By combining various AGN selection methods based on infrared (IR), radio, and X-ray data, we identify 2,688 AGN. We find that (i) $f_{\rm AGN}$ increases with $z_{\rm cl}$ and (ii) $f_{\rm AGN}$ decreases with $R/R_{\rm 200}$. The main contributors to the rapid increase of $f_{\rm AGN}$ towards high-$z$ and cluster center are IR- and radio-selected AGN, respectively. Those results indicate that the emergence of the AGN population depends on the environment and redshift, and galaxy groups and clusters at high-$z$ play an important role in AGN evolution. We also find that cluster-cluster mergers may not drive AGN activity in at least the cluster center, while we have tentative evidence that cluster-cluster mergers would enhance AGN activity in the outskirts of (particularly massive) galaxy clusters., Comment: 16 pages, 21 figures, and 2 tables, accepted for publication in PASJ

The physical origins of quasar components, such as the broad line region (BLR) and dust torus, remain under debate. To gain insights into them, we focused on Changing-State Quasars (CSQs) which provide a unique perspective through structural changes associated with accretion disk state transitions. We targeted SDSS J125809.31+351943.0, an extremely variable CSQ, to study its central core structure and kinematics. We conducted reverberation mapping with optical spectroscopy to explore the structure of the BLR and estimate the black hole mass. The results from H$\beta$ reverberation mapping indicated a black hole mass of $10^{9.64^{+0.11}_{-0.20}}\rm{M_\odot}$. Additionally, we analyzed variations in the optical to X-ray spectral indices, $\alpha_{\rm{ox}}$, before and after the state transition, to investigate the accretion disk. These variations in $\alpha_{\rm{ox}}$ and the Eddington ratio (from 0.4 \% to 2.4 \%) exhibitied behavior similar to state transitions observed in X-ray binary systems. Spectral analysis of H$\beta$ revealed a predominantly double-peaked profile during dim periods, transitioning to include a single-peaked component as the quasar brightened, suggesting that H$\beta$ contains a mixture of two components. Each of these components has its distinct characteristics: the first is a double-peaked profile that remains stable despite changes in the accretion rate, while the second is a variable single-peaked profile. Using time lags from reverberation mapping, we estimated the spatial relationships between these BLR components, the accretion disk, and the dust torus. Our results suggest that the BLR consists of two distinct components, each differing in location and origin., Comment: Accepted for publication in MNRAS. Comments are welcome

Radio galaxies are a key population to understand the importance of relativistic jets in AGN feedback. We present the results of a systematic, broadband 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 \textit{Swift}/BAT 70 month AGN catalog. The spectra from 0.5 keV up to 66 keV obtained with \textit{Suzaku} and \textit{NuSTAR} of six objects are newly analyzed here by utilizing the X-ray clumpy torus model (XCLUMPY), whereas we refer to Ogawa et al. (2021) 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 ($-3 < \log \lambda_{\rm Edd} < -1$). 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., Comment: 10 pages (4 tables/14 figures in the main text), accepted in MNRAS

In this multi-messenger astronomy era, all the observational probes are improving their sensitivities and overall performance. The Focusing on Relativistic universe and Cosmic Evolution (FORCE) mission, the product of a JAXA/NASA collaboration, will reach a 10 times higher sensitivity in the hard X-ray band ($E >$ 10~keV) in comparison with any previous hard X-ray missions, and provide simultaneous soft X-ray coverage. FORCE aims to be launched in the early 2030s, providing a perfect hard X-ray complement to the ESA flagship mission Athena. FORCE will be the most powerful X-ray probe for discovering obscured/hidden black holes and studying high energy particle acceleration in our Universe and will address how relativistic processes in the universe are realized and how these affect cosmic evolution. FORCE, which will operate over 1--79 keV, is equipped with two identical pairs of supermirrors and wideband X-ray imagers. The mirror and imager are connected by a high mechanical stiffness extensible optical bench with alignment monitor systems with a focal length of 12~m. A light-weight silicon mirror with multi-layer coating realizes a high angular resolution of $<15''$ in half-power diameter in the broad bandpass. The imager is a hybrid of a brand-new SOI-CMOS silicon-pixel detector and a CdTe detector responsible for the softer and harder energy bands, respectively. FORCE will play an essential role in the multi-messenger astronomy in the 2030s with its broadband X-ray sensitivity., Comment: 12 pages, 8 figures. Proceedings of SPIE Astronomical Telescopes and Instrumentation 2022

We present a statistical study of 180 dust continuum sources identified in 33 massive cluster fields by the ALMA Lensing Cluster Survey (ALCS) over a total of 133 arcmin$^{2}$ area, homogeneously observed at 1.2 mm. ALCS enables us to detect extremely faint mm sources by lensing magnification, including near-infrared (NIR) dark objects showing no counterparts in existing {\it Hubble Space Telescope} and {\it Spitzer} images. The dust continuum sources belong to a blind sample ($N=141$) with S/N $\gtrsim$ 5.0 (a purity of $>$ 0.99) or a secondary sample ($N=39$) with S/N= $4.0-5.0$ screened by priors. With the blind sample, we securely derive 1.2-mm number counts down to $\sim7$ $\mu$Jy, and find that the total integrated 1.2mm flux is 20.7$^{+8.5}_{-6.5}$ Jy deg$^{-2}$, resolving $\simeq$ 80 % of the cosmic infrared background light. The resolved fraction varies by a factor of $0.6-1.1$ due to the completeness correction depending on the spatial size of the mm emission. We also derive infrared (IR) luminosity functions (LFs) at $z=0.6-7.5$ with the $1/V_{\rm max}$ method, finding the redshift evolution of IR LFs characterized by positive luminosity and negative density evolution. The total (=UV+IR) cosmic star-formation rate density (SFRD) at $z>4$ is estimated to be $161^{+25}_{-21}$ % of the established measurements, which were almost exclusively based on optical$-$NIR surveys. Although our general understanding of the cosmic SFRD is unlikely to change beyond a factor of 2, these results add to the weight of evidence for an additional ($\approx 60$ %) SFRD component contributed by the faint-mm population, including NIR dark objects., Comment: ApJS in press, 34 pages, 8 Tables, and 18 Figures (+38 pages, 5 Tables, and 6 Figures in Appendix)

We report the discovery of a triply imaged active galactic nucleus (AGN), lensed by the galaxy cluster MACS J0035.4-2015 ($z_{\mathrm{d}}=0.352$). The object is detected in Hubble Space Telescope imaging taken for the RELICS program. It appears to have a quasi-stellar nucleus consistent with a point-source, with a de-magnified radius of $r_e\lesssim100$ pc. The object is spectroscopically confirmed to be an AGN at $z_{\mathrm{spec}}=2.063\pm0.005$ showing broad rest-frame UV emission lines, and is detected in both X-ray observations with Chandra and in ALCS ALMA band 6 (1.2 mm) imaging. It has a relatively faint rest-frame UV luminosity for a quasar-like object, $M_{\mathrm{UV},1450}=-19.7\pm0.2$. The object adds to just a few quasars or other X-ray sources known to be multiply lensed by a galaxy cluster. Some diffuse emission from the host galaxy is faintly seen around the nucleus and there is a faint object nearby sharing the same multiple-imaging symmetry and geometric redshift, possibly an interacting galaxy or a star-forming knot in the host. We present an accompanying lens model, calculate the magnifications and time delays, and infer physical properties for the source. We find the rest-frame UV continuum and emission lines to be dominated by the AGN, and the optical emission to be dominated by the host galaxy of modest stellar mass $M_{\star}\simeq10^{9.2} \mathrm{M}_{\odot}$. We also observe some variation in the AGN emission with time, which may suggest that the AGN used to be more active. This object adds a low-redshift counterpart to several relatively faint AGN recently uncovered at high redshifts with HST and JWST., Comment: Published in MNRAS. Corrected miss-assignment of affiliations in the author list

We construct the eROSITA X-ray catalog of radio galaxies discovered by the WERGS survey that is made by the cross-matching of the wide-area Subaru/HSC optical survey and VLA/FIRST 1.4 GHz radio survey. We find 393 eROSITA detected radio galaxies in the 0.5--2 keV band in the eFEDS field covering 140~deg$^2$. Thanks to the wide and medium depth eFEDS X-ray survey, the sample contains the rare and most X-ray luminous radio galaxies above the knee of the X-ray luminosity function, spanning 4422$. Those obscured and radio AGN reside in $0.4

We report the multi-wavelength properties of millimeter galaxies hosting X-ray detected active galactic nuclei (AGNs) from the ALMA Lensing Cluster Survey (ALCS). ALCS is an extensive survey of well-studied lensing clusters with ALMA, covering an area of 133 arcmin$^2$ over 33 clusters with a 1.2 mm flux-density limit of ${\sim}$60 $\mathrm{\mu Jy}$ ($1\sigma$). Utilizing the archival data of Chandra, we identify three AGNs at $z=$1.06, 2.09, and 2.84 among the 180 millimeter sources securely detected in the ALCS (of which 155 are inside the coverage of Chandra). The X-ray spectral analysis shows that two AGNs are not significantly absorbed ($\log N_{\mathrm{H}}/\mathrm{cm}^{-2} < 23$), while the other shows signs of moderate absorption ($\log N_{\mathrm{H}}/\mathrm{cm}^{-2}\sim 23.5$). We also perform spectral energy distribution (SED) modelling of X-ray to millimeter photometry. We find that our X-ray AGN sample shows both high mass accretion rates (intrinsic 0.5--8 keV X-ray luminosities of ${\sim}10^{\text{44--45}}\,\mathrm{erg\ s^{-1}}$) and star-formation rates (${\gtrsim}100\,M_{\odot}\,\mathrm{yr}^{-1}$). This demonstrates that a wide-area survey with ALMA and Chandra can selectively detect intense growth of both galaxies and supermassive black holes (SMBHs) in the high-redshift universe., Comment: 14 pages, 3 figures, 2 tables

We conduct a hard X-ray to radio multiwavelength spectral energy distribution (SED) decomposition for 57 local luminous and ultraluminous infrared galaxies (U/LIRGs) observed with Nuclear Spectroscopic Telescope Array and/or Swift/Burst Alert Telescope in GOALS (Armus et al. 2009) sample. We modify the latest SED-fitting code X-CIGALE by implementing the infrared (IR) CLUMPY model, allowing the multiwavelength study with the X-ray torus model (XCLUMPY) self-consistently. Adopting the torus parameters obtained by the X-ray fitting (Yamada et al. 2021), we estimate the properties of 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 $\sim$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 is likely the expanding (i.e., evolving) dusty outflows. The comparison between SFRs and intrinsic AGN luminosities suggests that the starbursts occur first and AGNs arise later, and overall their growth rates follow the simultaneous coevolution relation that can establish the 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., Comment: 84 pages (5 tables/29 figures in the main text and 8 tables/18 figures in the Appendix), accepted in ApJS

We report optical spectroscopic observations of four blue-excess dust-obscured galaxies (BluDOGs) identified by Subaru Hyper Suprime-Cam. BluDOGs are a sub-class of dust-obscured galaxies (DOGs, defined with the extremely red color $(i-[22])_{\rm AB} \geq 7.0$; Toba et al. 2015), showing a significant flux excess in the optical $g$- and $r$-bands over the power-law fits to the fluxes at the longer wavelengths. Noboriguchi et al. (2019) has suggested that BluDOGs may correspond to the blowing-out phase involved in a gas-rich major merger scenario. However the detailed properties of BluDOGs are not understood because of the lack of spectroscopic information. In this work, we carry out deep optical spectroscopic observations of four BluDOGs using Subaru/FOCAS and VLT/FORS2. The obtained spectra show broad emission lines with extremely large equivalent widths, and a blue wing in the CIV line profile. The redshifts are between 2.2 and 3.3. The averaged rest-frame equivalent widths of the CIV lines are $160\pm33$ $\mathrm{\mathring{A}}$, $\sim$7 times higher than the average of a typical type-1 quasar. The FWHMs of their velocity profiles are between 1990 and 4470 ${\rm km\ s^{-1}}$, and their asymmetric parameters are 0.05 and 0.25. Such strong CIV lines significantly affect the broad-band magnitudes, which is partly the origin of the blue excess seen in the spectral energy distribution of BluDOGs. Their estimated supermassive black hole masses are $1.1\times10^8 < M_{\rm BH}/M_\odot < 5.5 \times 10^8$. The inferred Eddington ratios of the BluDOGs are higher than 1 ($1.1< \lambda_{\rm Edd} < 3.8$), suggesting that the BluDOGs are in a rapidly evolving phase of supermassive black holes., Comment: 22 pages, 12 figures, accepted for publication in ApJ

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 $\sim$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; Tanimoto et al. 2019). 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 $1.0 \times 10^{43}$ and $7.5 \times 10^{41}\ \rm{erg}\ \rm{s}^{-1}$ absorbed by hydrogen column densities of $N_{\rm{H}} < 6.5 \times 10^{19}\ \rm{cm}^{-2}$ and $N_{\rm{H}} = 6.9^{+3.2}_{-1.7} \times 10^{21}\ \rm{cm}^{-2}$, respectively. The torus covering fraction of the material with $N_{\rm{H}} > 10^{22} \rm{cm}^{-2}$ in Mrk 739E, $C_{\rm{T}}^{(22)} < 0.50$ at a 90% confidence limit, is found to be smaller than those found for late-merger ultra/luminous infrared galaxies, $C_{\rm{T}}^{(22)} = 0.71\pm0.16$ (mean and standard deviation; Yamada et al. 2021). 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 late merger., Comment: 14 pages, 4 figures, 3 tables, accepted for publication in ApJ

We constrain the intrinsic Eddington ratio (\lamEdd ) distribution function for local AGN in bins of low and high obscuration (log NH <= 22 and 22 < log NH < 25), using the Swift-BAT 70-month/BASS DR2 survey. We interpret the fraction of obscured AGN in terms of circum-nuclear geometry and temporal evolution. Specifically, at low Eddington ratios (log lamEdd < -2), obscured AGN outnumber unobscured ones by a factor of ~4, reflecting the covering factor of the circum-nuclear material (0.8, or a torus opening angle of ~ 34 degrees). At high Eddington ratios (\log lamEdd > -1), the trend is reversed, with < 30% of AGN having log NH > 22, which we suggest is mainly due to the small fraction of time spent in a highly obscured state. Considering the Eddington ratio distribution function of narrow-line and broad-line AGN from our prior work, we see a qualitatively similar picture. To disentangle temporal and geometric effects at high lamEdd, we explore plausible clearing scenarios such that the time-weighted covering factors agree with the observed population ratio. We find that the low fraction of obscured AGN at high lamEdd is primarily due to the fact that the covering factor drops very rapidly, with more than half the time is spent with < 10% covering factor. We also find that nearly all obscured AGN at high-lamEdd exhibit some broad-lines. We suggest that this is because the height of the depleted torus falls below the height of the broad-line region, making the latter visible from all lines of sight., Comment: Accepted by ApJL

In the paper, we develop an $L^1_k\cap L^p_k$ approach to construct global solutions to the Cauchy problem on the non-cutoff Boltzmann equation near equilibrium in $\mathbb{R}^3$. In particular, only smallness of $\|\mathcal{F}_x{f}_0\|_{L^1\cap L^p (\mathbb{R}^3_k;L^2(\mathbb{R}^3_v))}$ with $3/2

Statistical studies of X-ray selected Active Galactic Nuclei (AGN) indicate that the fraction of obscured AGN increases with increasing redshift, and the results suggest that a significant part of the accretion growth occurs behind obscuring material in the early universe. We investigate the obscured fraction of highly accreting X-ray AGN at around the peak epoch of supermassive black hole growth utilizing the wide and deep X-ray and optical/IR imaging datasets. A unique sample of luminous X-ray selected AGNs above $z>2$ was constructed by matching the XMM-SERVS X-ray point-source catalog with a PSF-convolved photometric catalog covering from $u^*$ to 4.5$\mu \mathrm{m}$ bands. Photometric redshift, hydrogen column density, and 2-10 keV AGN luminosity of the X-ray selected AGN candidates were estimated. Using the sample of 306 2-10 keV detected AGN at above redshift 2, we estimate the fraction of AGN with $\log N_{\rm H}\ (\rm cm^{-2})>22$, assuming parametric X-ray luminosity and absorption functions. The results suggest that $76_{-3}^{+4}\%$ of luminous quasars ($\log L_X\ (\rm erg\ s^{-1}) >44.5$) above redshift 2 are obscured. The fraction indicates an increased contribution of obscured accretion at high redshift than that in the local universe. We discuss the implications of the increasing obscured fraction with increasing redshift based on the AGN obscuration scenarios, which describe obscuration properties in the local universe. Both the obscured and unobscured $z>2$ AGN show a broad range of SEDs and morphology, which may reflect the broad variety of host galaxy properties and physical processes associated with the obscuration., Comment: 25 Pages, 19 Figure, ApJ accepted. Updated version contains corrections based on comments from the community

We present ionized gas properties of 9 local ultra/luminous infrared galaxies (U/LIRGs) at $z <$ 0.04 through IFU observations with KOOLS-IFU on Seimei Telescope. The observed targets are drawn from the Great Observatories All-sky LIRG Survey (GOALS), covering a wide range of merger stages. We successfully detect emission lines such as H$\beta$, [OIII]$\lambda$5007, H$\alpha$, [NII]$\lambda\lambda$6549,6583, and [SII]$\lambda\lambda$6717,6731 with a spectral resolution of $R$ = 1500-2000, which provides (i) spatially-resolved ($\sim$200-700 pc) moment map of ionized gas and (ii) diagnostics for active galactic nucleus (AGN) within the central $\sim$3--11 kpc in diameter for our sample. We find that [OIII] outflow that is expected to be driven by AGN tends to be stronger (i) towards the galactic center and (ii) as a sequence of merger stage. In particular, the outflow strength in the late-stage (stage D) mergers is about 1.5 times stronger than that in the early-state (stage B) mergers, which indicates that galaxy mergers could induce AGN-driven outflow and play an important role in the co-evolution of galaxies and supermassive black holes., Comment: 12 pages, 8 figures, and 2 tables, accepted for publication in PASJ

To understand the origin of nuclear ($\lesssim$ 100 pc) millimeter-wave (mm-wave) continuum emission in active galactic nuclei (AGNs), we systematically analyzed sub-arcsec resolution Band-6 (211-275 GHz) ALMA data of 98 nearby AGNs ($z <$ 0.05) from the 70-month Swift/BAT catalog. The sample, almost unbiased for obscured systems, provides the largest number of AGNs to date with high mm-wave spatial resolution sampling ($\sim$ 1-200 pc), and spans broad ranges of 14-150 keV luminosity {$40 < \log[L_{\rm 14-150}/({\rm erg\,s^{-1}})] < 45$}, black hole mass [$5 < \log(M_{\rm BH}/M_\odot) < 10$], and Eddington ratio ($-4 < \log \lambda_{\rm Edd} < 2$). We find a significant correlation between 1.3 mm (230 GHz) and 14-150 keV luminosities. Its scatter is $\approx$ 0.36 dex, and the mm-wave emission may serve as a good proxy of the AGN luminosity, free of dust extinction up to $N_{\rm H} \sim 10^{26}$ cm$^{-2}$. While the mm-wave emission could be self-absorbed synchrotron radiation around the X-ray corona according to past works, we also discuss different possible origins of the mm-wave emission; AGN-related dust emission, outflow-driven shocks, and a small-scale ($<$ 200 pc) jet. The dust emission is unlikely to be dominant, as the mm-wave slope is generally flatter than expected. Also, due to no increase in the mm-wave luminosity with the Eddington ratio, a radiation-driven outflow model is possibly not the common mechanism. Furthermore, we find independence of the mm-wave luminosity on indicators of the inclination angle from the polar axis of the nuclear structure, which is inconsistent with a jet model whose luminosity depends only on the angle., Comment: 44 pages, 35 figures, 3 tables, accepted for publication in ApJ; modified format, added supplementary figure (Fig. 32)

We present an ALMA-Herschel joint analysis of sources detected by the ALMA Lensing Cluster Survey (ALCS) at 1.15 mm. Herschel/PACS and SPIRE data at 100-500 $\mu$m are deblended for 180 ALMA sources in 33 lensing cluster fields that are either detected securely (141 sources; in our main sample) or tentatively at S/N$\geq$4 with cross-matched HST/Spitzer counterparts, down to a delensed 1.15-mm flux density of $\sim0.02$ mJy. We performed far-infrared spectral energy distribution modeling and derived the physical properties of dusty star formation for 125 sources (109 independently) that are detected at $>2\sigma$ in at least one Herschel band. 27 secure ALCS sources are not detected in any Herschel bands, including 17 optical/near-IR-dark sources that likely reside at $z=4.2\pm1.2$. The 16-50-84 percentiles of the redshift distribution are 1.15-2.08-3.59 for ALCS sources in the main sample, suggesting an increasing fraction of $z\simeq1-2$ galaxies among fainter millimeter sources ($f_{1150}\sim 0.1$ mJy). With a median lensing magnification factor of $\mu = 2.6_{-0.8}^{+2.6}$, ALCS sources in the main sample exhibit a median intrinsic star-formation rate of $94_{-54}^{+84}\,\mathrm{M}_\odot\,\mathrm{yr}^{-1}$, lower than that of conventional submillimeter galaxies at similar redshifts by a factor of $\sim$3. Our study suggests weak or no redshift evolution of dust temperature with $L_\mathrm{IR}<10^{12}\,\mathrm{L}_\odot$ galaxies within our sample at $z \simeq 0 - 2$. At $L_\mathrm{IR}>10^{12}\,\mathrm{L}_\odot$, the dust temperatures show no evolution across $z \simeq 1 -4$ while being lower than those in the local Universe. For the highest-redshift source in our sample ($z=6.07$), we can rule out an extreme dust temperature ($>$80 K) that was reported for MACS0416 Y1 at $z=8.31$., Comment: 44 pages, 23 figures, 4 tables, accepted for publication in ApJ

We present the systematic broadband X-ray spectral analysis of 52 Compton-thick ($24 \leq \log N_{\mathrm{H}}^{\mathrm{LOS}}/\mathrm{cm}^{-2}$) active galactic nucleus (CTAGN) candidates selected by the Swift/BAT all-sky hard X-ray survey observed with Chandra, XMM--Newton, Swift/XRT, Suzaku, and NuSTAR. The XMM--Newton data of 10 objects and the NuSTAR data of 15 objects are published for the first time. We use an X-ray spectral model from a clumpy torus (XClumpy) to determine the torus properties. As a result, the hydrogen column density along the line of sight $N_{\mathrm{H}}^{\mathrm{LOS}}$ obtained from the XClumpy model indicate that 24 objects are Compton-thin AGNs and 28 objects are Compton-thick AGNs in the 90\% confidence interval. The main reason is the difference in the torus model applied. The hydrogen column density along the equatorial direction $N_{\mathrm{H}}^{\mathrm{Equ}}$ of CTAGNs inferred from the XClumpy model is larger than that of less obscured AGNs. The Compton-thin torus covering factor $C_{22}$ obtained from the XClumpy model is consistent with that of Ricci et al. (2017) in the low Eddington ratio ($\log R_{\mathrm{Edd}} \leq -1.0$), whereas $C_{22}$ inferred from the XClumpy model is larger than that of Ricci et al. (2017) in the high Eddington ratio ($-1.0 \leq \log R_{\mathrm{Edd}}$). The average value of the Compton-thick torus covering factor $C_{24}$ obtained from the XClumpy model is $36_{-4}^{+4}$\%. This value is larger than that of Ricci et al. (2015) ($C_{24} \simeq 27_{-4}^{+4}$\%) based on the assumption that all AGNs have intrinsically the same torus structure. These results suggest that the structure of CTAGN may be intrinsically different from that of less obscured AGN., Comment: 44 pages, 16 figures, accepted for publication in the Astrophysical Journal Supplement Series

We present the second catalog and data release of optical spectral line measurements and AGN demographics of the BAT AGN Spectroscopic Survey, which focuses on the of Swift-BAT hard X-ray detected AGNs. We use spectra from dedicated campaigns and publicly available archives to investigate spectral properties of most of the AGNs listed in the 70-month Swift-BAT all-sky catalog; specifically, 743 of the 746 unbeamed and unlensed AGNs (99.6%). We find a good correspondence between the optical emission line widths and the hydrogen column density distributions using the X-ray spectra, with a clear dichotomy of AGN types for NH = 10^22 cm-2. Based on optical emission-line diagnostics, we show that 48%-75% of BAT AGNs are classified as Seyfert, depending on the choice of emission lines used in the diagnostics. The fraction of objects with upper limits on line emission varies from 6% to 20%. Roughly 4% of the BAT AGNs have lines too weak to be placed on the most commonly used diagnostic diagram, [O III]{\lambda}5007/H\b{eta} versus [N II]{\lambda}6584/H{\alpha}, despite the high signal-to-noise ratio (S/N) of their spectra. This value increases to 35% in the [O III]{\lambda}5007/[O II]{\lambda}3727 diagram, owing to difficulties in line detection. Compared to optically-selected narrow-line AGNs in the Sloan Digital Sky Survey, the BAT narrow-line AGNs have a higher rate of reddening/extinction, with H{\alpha}/H\b{eta} > 5 (~ 36%), indicating that hard X-ray selection more effectively detects obscured AGNs from the underlying AGN population. Finally, we present a subpopulation of AGNs that feature complex broad-lines (34%, 250/743) or double-peaked narrow emission lines (2%, 17/743)., Comment: 30 pages, 17 figures, 11 tables, accepted for publication in ApJS; part of BASS DR2 special issue

We report the results from the broad-band X-ray monitoring of the new Galactic black hole candidate MAXI J1803$-$298 with the MAXI/GSC and Swift/BAT during its outburst. After the discovery on 2021 May 1, the soft X-ray flux below 10 keV rapidly increased for $\sim 10$ days and then have been gradually decreasing over 5 months. At the brightest phase, the source exhibited the state transition from the low/hard state to the high/soft state via the intermediate state. The broad-band X-ray spectrum during the outburst was well described with a disk blackbody plus its thermal or non-thermal Comptonization. Before the transition the source spectrum was described by a thermal Comptonization component with a photon index of $\sim 1.7$ and an electron temperature of $\sim 30$ keV, whereas a strong disk blackbody component was observed after the transition. The spectral properties in these periods are consistent with the low/hard state and the high/soft state, respectively. A sudden flux drop with a few days duration, unassociated with a significant change in the hardness ratio, was found in the intermediate state. A possible cause of this variation is that the mass accretion rate rapidly increased at the disk transition, which induced a strong Compton-thick outflow and scattered out the X-ray flux. Assuming a non-spinning black hole, we estimated a black hole mass of MAXI J1803$-$298 as $5.8 \pm 0.4~(\cos i/\cos 70^\circ)^{-1/2} (D/8~\mathrm{kpc})~M_\odot$ (where $i$ and $D$ are the inclination angle and the distance) from the inner disk radius obtained in the high/soft state., Comment: 13 pages, 10 figures, Accepted for publication in ApJ

We determine the low-redshift X-ray luminosity function (XLF), active black hole mass function (BHMF), and Eddington-ratio distribution function (ERDF) for both unobscured (Type 1) and obscured (Type 2) active galactic nuclei (AGN) using the unprecedented spectroscopic completeness of the BAT AGN Spectroscopic Survey (BASS) data release 2. In addition to a straightforward 1/Vmax approach, we also compute the intrinsic distributions, accounting for sample truncation by employing a forward modeling approach to recover the observed BHMF and ERDF. As previous BHMFs and ERDFs have been robustly determined only for samples of bright, broad-line (Type 1) AGNs and/or quasars, ours is the first directly observationally constrained BHMF and ERDF of Type 2 AGN. We find that after accounting for all observational biases, the intrinsic ERDF of Type 2 AGN is significantly skewed towards lower Eddington ratios than the intrinsic ERDF of Type 1 AGN. This result supports the radiation-regulated unification scenario, in which radiation pressure dictates the geometry of the dusty obscuring structure around an AGN. Calculating the ERDFs in two separate mass bins, we verify that the derived shape is consistent, validating the assumption that the ERDF (shape) is mass independent. We report the local AGN duty cycle as a function of mass and Eddington ratio, by comparing the BASS active BHMF with the local mass function for all SMBH. We also present the log N-log S of Swift-BAT 70-month sources., Comment: Accepted by APJS

To investigate the origins of the warm absorbers in active galactic nuclei (AGNs), we study the ionization-state structure of the radiation-driven fountain model in a low-mass AGN (Wada et al. 2016) and calculate the predicted X-ray spectra, utilizing the spectral synthesis code Cloudy (Ferland et al. 2017). The spectra show many absorption and emission line features originated in the outflowing ionized gas. The O VIII 0.654 keV lines are produced mainly in the polar region much closer to the SMBH than the optical narrow line regions. The absorption measure distribution of the ionization parameter ($\xi$) at a low inclination spreads over 4 orders of magnitude in $\xi$, indicating multi-phase ionization structure of the outflow, as actually observed in many type-1 AGNs. We compare our simulated spectra with the high energy-resolution spectrum of the narrow line Seyfert 1 galaxy, NGC 4051. The model reproduces slowly outflowing (a few hundreds km s$^{-1}$) warm absorbers. However, the faster components with a few thousands km s$^{-1}$ observed in NGC 4051 are not reproduced. The simulation also underproduces the intensity and width of the O VIII 0.654 keV line. These results suggest that the ionized gas launched from sub-parsec or smaller regions inside the torus, which are not included in the current fountain model, must be important ingredients of the warm absorbers with a few thousands km s$^{-1}$. The model also consistently explains the Chandra/HETG spectrum of the Seyfert 2 galaxy, the Circinus galaxy., Comment: 13 pages, 13 figures, accepted for publication in ApJ

We present the optical and infrared properties of 39 extremely radio-loud galaxies discovered by cross-matching the Subaru/Hyper Suprime-Cam (HSC) deep optical imaging survey and VLA/FIRST 1.4 GHz radio survey. The recent Subaru/HSC strategic survey revealed optically-faint radio galaxies (RG) down to $g_\mathrm{AB} \sim 26$, opening a new parameter space of extremely radio-loud galaxies (ERGs) with radio-loudness parameter of $\log \mathcal{R}_\mathrm{rest} = \log (f_{1.4 \mathrm{GHz,rest}}/f_{g,\mathrm{rest}}) >4$. Because of their optical faintness and small number density of $\sim1~$deg$^{-2}$, such ERGs were difficult to find in the previous wide but shallow, or deep but small area optical surveys. ERGs show intriguing properties that are different from the conventional RGs: (1) most ERGs reside above or on the star-forming main-sequence, and some of them might be low-mass galaxies with $\log (M_\star/M_\odot) < 10$. (2) ERGs exhibit a high specific black hole accretion rate, reaching the order of the Eddington limit. The intrinsic radio-loudness ($\mathcal{R}_\mathrm{int}$), defined by the ratio of jet power over bolometric radiation luminosity, is one order of magnitude higher than that of radio quasars. This suggests that ERGs harbor a unique type of active galactic nuclei (AGN) that show both powerful radiations and jets. Therefore, ERGs are prominent candidates of very rapidly growing black holes reaching Eddington-limited accretion just before the onset of intensive AGN feedback., Comment: 20 pages, 10 figures, accepted for publication in ApJ

We perform a systematic X-ray spectroscopic analysis of 57 local ultra/luminous infrared galaxy systems (containing 84 individual galaxies) observed with Nuclear Spectroscopic Telescope Array and/or Swift/BAT. Combining soft X-ray data obtained with Chandra, XMM-Newton, Suzaku and/or Swift/XRT, we identify 40 hard ($>$10 keV) X-ray detected active galactic nuclei (AGNs) and constrain their torus parameters with the X-ray clumpy torus model XCLUMPY (Tanimoto et al. 2019). Among the AGNs at $z < 0.03$, for which sample biases are minimized, the fraction of Compton-thick ($N_{\rm H} \geq 10^{24}$ cm$^{-2}$) AGNs reaches 64$^{+14}_{-15}$% (6/9 sources) in late mergers, while 24$^{+12}_{-10}$% (3/14 sources) in early mergers, consistent with the tendency reported by Ricci et al. (2017). We find that the bolometric AGN luminosities derived from the infrared data increase, but the X-ray to bolometric luminosity ratios decrease, with merger stage. The X-ray weak AGNs in late mergers ubiquitously show massive outflows at sub-pc to kpc scales. Among them, the most luminous AGNs ($L_{\rm bol,AGN} \sim 10^{46}$ erg s$^{-1}$) have relatively small column densities of $\lesssim$10$^{23}$ cm$^{-2}$ and almost super-Eddington ratios ($\lambda_{\rm Edd} \sim$ 1.0). Their torus covering factors ($C_{\rm T}^{\rm (22)} \sim 0.6$) are larger than those of Swift/BAT selected AGNs with similarly high Eddington ratios. These results suggest a scenario that, in the final stage of mergers, multiphase strong outflows are produced due to chaotic quasi-spherical inflows and the AGN becomes extremely X-ray weak and deeply buried due to obscuration by inflowing and/or outflowing material., Comment: 85 pages, 88 figures, accepted in ApJS

We construct a new catalog of extragalactic X-ray binaries (XRBs) by matching the latest Chandra source catalog with local galaxy catalogs. Our XRB catalog contains 4430 XRBs hosted by 237 galaxies within ~130 Mpc. As XRBs dominate the X-ray activity in galaxies, the catalog enables us to study the correlations between the total X-ray luminosity of a galaxy $L_{X,\rm tot}$, star formation rate $\dot{\rho}_\star$, and stellar mass $M_\star$. As previously reported, $L_{X,\rm tot}$ is correlated with $\dot{\rho}_\star$ and $M_\star$. In particular, we find that there is a fundamental plane in those three parameters as $\log L_{X,\rm tot}={38.80^{+0.09}_{-0.12}}+\log(\dot{\rho}_\star + \alpha M_\star)$, where $\alpha = {(3.36\pm1.40)\times10^{-11}}\ {\rm yr^{-1}}$. In order to investigate this relation, we construct a phenomenological binary population synthesis model. We find that the high mass XRB and low mass XRB fraction in formed compact object binary systems is ~9% and ~0.04%, respectively. Utilizing the latest XMM-Newton, and Swift X-ray source catalog data sets, additional XRB candidates are also found resulting in 5757 XRBs hosted by 311 galaxies., Comment: 18 pages, 18 figures, accepted for publication in PASJ

We investigate the physical properties--such as the stellar mass, SFR, IR luminosity, X-ray luminosity, and hydrogen column density--of MIR galaxies and AGN at $z < 4$ in the 140 deg$^2$ field observed by SRG/eROSITA through the eFEDS survey. By cross-matching the WISE 22 $\mu$m (W4)-detected sample and the eFEDS X-ray point-source catalog, we find that 692 extragalactic objects are detected by eROSITA. We have compiled a multiwavelength dataset. We have also performed (i) an X-ray spectral analysis, (ii) SED fitting using X-CIGALE, (iii) 2D image-decomposition analysis using Subaru HSC images, and (iv) optical spectral fitting with QSFit to investigate the AGN and host-galaxy properties. For 7,088 WISE W4 objects that are undetected by eROSITA, we have performed an X-ray stacking analysis to examine the typical physical properties of these X-ray faint and/or probably obscured objects. We find that (i) 82% of the eFEDS-W4 sources are classified as X-ray AGN with $\log\,L_{\rm X} >$ 42 erg s$^{-1}$; (ii) 67% and 24% of the objects have $\log\,(L_{\rm IR}/L_{\odot}) > 12$ and 13, respectively; (iii) the relationship between $L_{\rm X}$ and the 6 $\mu$m luminosity is consistent with that reported in previous works; and (iv) the relationship between the Eddington ratio and $N_{\rm H}$ for the eFEDS-W4 sample and a comparison with a model prediction from a galaxy-merger simulation indicates that approximately 5% of the eFEDS-W4 sources in our sample are likely to be in an AGN-feedback phase, in which strong radiation pressure from the AGN blows out the surrounding material from the nuclear region. Thanks to the wide area coverage of eFEDS, we have been able to constrain the ranges of the physical properties of the WISE W4 sample of AGNs at $z < 4$, providing a benchmark for forthcoming studies on a complete census of MIR galaxies selected from the full-depth eROSITA all-sky survey., Comment: 18 pages, 19 figures, and 3 tables, accepted to appear on A&A, Special Issue: The Early Data Release of eROSITA and Mikhail Pavlinsky ART-XC on the SRG Mission

We report on a spectroscopic program to search for dual quasars using Subaru Hyper Suprime-Cam (HSC) images of SDSS quasars which represent an important stage during galaxy mergers. Using Subaru/FOCAS and Gemini-N/GMOS, we identify three new physically associated quasar pairs having projected separations less than 20 kpc, out of 26 observed candidates. These include the discovery of the highest redshift ($z=3.1$) quasar pair with a separation $<$ 10 kpc. Based on the sample acquired to date, the success rate of identifying physically associated dual quasars is $19\%$ when excluding stars based on their HSC colors. Using the full sample of six spectroscopically confirmed dual quasars, we find that the black holes in these systems have black hole masses ($M_{BH} \sim 10^{8-9}M_{\odot}$) similar to single SDSS quasars as well as their bolometric luminosities and Eddington ratios. We measure the stellar mass of their host galaxies based on 2D image decomposition of the five-band ($grizy$) optical emission and assess the mass relation between supermassive black holes (SMBHs) and their hosts. Dual SMBHs appear to have elevated masses relative to their host galaxies. Thus mergers may not necessarily align such systems onto the local mass relation, as suggested by the Horizon-AGN simulation. This study suggests that dual luminous quasars are triggered prior to the final coalescence of the two SMBHs, resulting in early mass growth of the black holes relative to their host galaxies., Comment: 36 pages, 21 figures, 4 tables

We present ALMA [CII] 158 $\mu$m line and underlying far-infrared (FIR) continuum emission observations ($0''.70 \times 0''.56$ resolution) toward HSC J124353.93$+$010038.5 (J1243$+$0100) at $z = 7.07$, the only low-luminosity ($M_{\rm 1450} > -25$ mag) quasar currently known at $z > 7$. The FIR continuum is bright (1.52 mJy) and resolved with a total luminosity of $L_{\rm FIR} = 3.5 \times 10^{12}~L_\odot$. The spatially extended component is responsible for $\sim 40\%$ of the emission. The area-integrated [CII] spectrum shows a broad wing (${\rm FWHM} = 997$ km s$^{-1}$, $L_{\rm [CII]} = 1.2 \times 10^9~L_\odot$) as well as a bright core (${\rm FWHM} = 235$ km s$^{-1}$, $L_{\rm [CII]} = 1.9 \times 10^9~L_\odot$). This wing is the first detection of a galactic-scale quasar-driven outflow (atomic outflow rate $> 447~M_\odot$ yr$^{-1}$) at $z > 7$. The estimated large mass loading factor of the total outflow (e.g., $\gtrsim 9$ relative to the [CII]-based SFR) suggests that this outflow will soon quench the star-formation of the host. The core gas dynamics are governed by rotation, with a rotation curve suggestive of a compact bulge ($\sim 3.3 \times 10^{10}~M_\odot$), although it is not yet spatially resolved. Finally, we found that J1243$+$0100 has a black hole mass-to-dynamical mass ratio (and -to-bulge mass ratio) of $\sim 0.4\%$ ($\sim 1\%$), consistent with the local value within uncertainties. Our results therefore suggest that the black hole-host co-evolution relation is already in place at $z \sim 7$ for this object., Comment: Slightly revised version after the proof correction. 22 pages, 13 figures, 6 tables. Accepted for publication in ApJ

In this study, we investigate the X-ray properties of WISE J090924.01+000211.1 (WISEJ0909+0002), an extremely luminous infrared (IR) galaxy (ELIRG) at $z_{\rm spec}$= 1.871 in the eROSITA final equatorial depth survey (eFEDS). WISEJ0909+0002 is a WISE 22 $\mu$m source, located in the GAMA-09 field, detected by eROSITA during the performance and verification phase. The corresponding optical spectrum indicates that this object is a type-1 active galactic nucleus (AGN). Observations from eROSITA combined with Chandra and XMM-Newton archival data indicate a very luminous ($L$ (2--10 keV) = ($2.1 \pm 0.2) \times 10^{45}$ erg s$^{-1}$) unobscured AGN with a power-law photon index of $\Gamma$ = 1.73$_{-0.15}^{+0.16}$, and an absorption hydrogen column density of $\log\,(N_{\rm H}/{\rm cm}^{-2}) < 21.0$. The IR luminosity was estimated to be $L_{\rm IR}$ = (1.79 $\pm$ 0.09) $\times 10^{14}\, L_{\odot}$ from spectral energy distribution modeling based on 22 photometric data (X-ray to far-IR) with X-CIGALE, which confirmed that WISEJ0909+0002 is an ELIRG. A remarkably high $L_{\rm IR}$ despite very low $N_{\rm H}$ would indicate that we are witnessing a short-lived phase in which hydrogen gas along the line of sight is blown outwards, whereas warm and hot dust heated by AGNs still exist. As a consequence of eROSITA all-sky survey, $6.8_{-5.6}^{+16}\times 10^2$ such X-ray bright ELIRGs are expected to be discovered in the entire extragalactic sky ($|b| > 10^\circ$). This can potentially be the key population to constrain the bright-end of IR luminosity functions., Comment: 10 pages, 5 figures, and 3 tables, accepted for publication in A&A Letters (special Issue: First science highlights from SRG/eROSITA)

The location of the obscuring "torus" in an active galactic nucleus (AGN) is still an unresolved issue. The line widths of X-ray fluorescence lines originated from the torus, particularly Fe K$\alpha$, carry key information on the radii of line emitting regions. Utilizing XCLUMPY (Tanimoto et al. 2019), an X-ray clumpy torus model, we develop a realistic model of emission line profiles from an AGN torus where we take into account line broadening due to the Keplerian motion around the black hole. Then, we apply the updated model to the best available broadband spectra (3-100 keV) of the Circinus galaxy observed with Suzaku, XMM-Newton, Nuclear Spectroscopic Telescope Array (NuSTAR), and Chandra, including 0.62 Ms Chandra/HETG data. We confirm that the torus is Compton-thick (hydrogen column-density along the equatorial plane is $N_\mathrm{H}^\mathrm{Equ}=2.16^{+0.24}_{-0.16}\times 10^{25}\ \mathrm{cm}^{-2}$), geometrically thin (torus angular width $\sigma=10.3^{+0.7}_{-0.3}\ \mathrm{degrees}$), viewed edge-on (inclination $i=78.3^{+0.4}_{-0.9}\ \mathrm{degrees}$), and has super-solar abundance ($1.52^{+0.04}_{-0.06}$ times solar). Simultaneously analyzing the Chandra/HETG first, second, and third order spectra with consideration of the spatial extent of the Fe K$\alpha$ line emitting region, we constrain the inner radius of the torus to be $1.9^{+3.1}_{-0.8}\times 10^5$ times the gravitational radius, or $1.6^{+1.5}_{-0.9}\times 10^{-2}\ \mathrm{pc}$ for a black hole mass of $(1.7\pm 0.3)\times 10^6\ M_{\odot}$. This is about 3 times smaller than that estimated from the dust sublimation radius, suggesting that the inner side of the dusty region of the torus is composed of dust-free gas., Comment: 20 pages, 10 figures, 8 tables, accepted for publication in ApJ

We report the discovery of possible periodic X-ray dips in a pulsating ultraluminous X-ray source, M51 ULX-7, with the archival Changra observations. With ~20 days of monitoring in the superorbital descending state, we discovered three dips with separations of ~2 and ~8 days via the Bayesian block technique. A phase-dispersion minimization and a $\chi^2$ test suggest that the dip is likely recurrent with a period of ~2 days, consistent with the orbital period of M51 ULX-7. We interpret the dip as an obscuring of the emission from the pulsar by the vertical structure on the stream-disk interaction region or the atmosphere of the companion star. Both interpretations suggest the viewing angle to be ~60 degrees. Given that the magnetic field of M51 ULX-7 is moderately high, $B\sim10^{13}$ G, low geometric beaming with $b\lesssim1/2$ is sufficient to explain the observed flux and the presence of dips. Obscuration of the stellar wind remains an alternative possible origin and further monitoring of the dips will be required., Comment: 8 pges, 4 figures, accepted for publication in ApJ

We report on the X-ray properties of the new transient Swift J0840.7$-$3516, discovered with Swift/BAT in 2020 February, using extensive data of Swift, MAXI, NICER, and NuSTAR. The source flux increased for $\sim 10^3$ s after the discovery, decayed rapidly over $\sim$ 5 orders of magnitude in 5 days, and then remained almost constant over 9 months. Large-amplitude short-term variations on time scales of 1--$10^4$ s were observed throughout the decay. In the initial flux rise, the source showed a hard power-law shaped spectrum with a photon index of $\sim 1.0$ extending up to $\sim 30$ keV, above which an exponential cutoff was present. The photon index increased in the following rapid decay and became $\sim 2$ at the end of the decay. A spectral absorption feature at 3--4 keV was detected in the decay. It is not straightforward to explain all the observed properties by any known class of X-ray sources. We discuss the possible nature of the source, including a Galactic low mass X-ray binary with multiple extreme properties and a tidal disruption event by a supermassive black hole or a Galactic neutron star., Comment: 15 pages, 10 figures, 3 tables, Accepted for publication in ApJ

We revisit the dependence of covering factor (CF) of dust torus on physical properties of active galactic nuclei (AGNs) by taking into account an AGN polar dust emission. The CF is converted from a ratio of infrared (IR) luminosity contributed from AGN dust torus ($L_{\rm IR}^{\rm torus}$) and AGN bolometric luminosity ($L_{\rm bol}$), by assuming a non-linear relation between luminosity ratio and intrinsic CF. We select 37,181 type 1 quasars at $z < 0.7$ from the Sloan Digital Sky Survey Data Release 16 quasar catalog. Their $L_{\rm bol}$, black hole mass ($M_{\rm BH}$), and Eddington ratio ($\lambda_{\rm Edd}$) are derived by spectral fitting with QSFit. We conduct spectral energy distribution decomposition by using X-CIGALE with clumpy torus and polar dust model to estimate $L_{\rm IR}^{\rm torus}$ without being affected by the contribution of stellar and AGN polar dust to IR emission. For 5720 quasars whose physical quantities are securely determined, we perform a correlation analysis on CF and (i) $L_{\rm bol}$, (ii) $M_{\rm BH}$, and (iii) $\lambda_{\rm Edd}$. As a result, anti-correlations for CF-$L_{\rm bol}$, CF-$M_{\rm BH}$, and CF-$\lambda_{\rm Edd}$ are confirmed. We find that incorporating the AGN polar dust emission makes those anti-correlations stronger which are compared to those without considering it. This indicates that polar dust wind provably driven by AGN radiative pressure is one of the key components to regulate obscuring material of AGNs., Comment: 20 pages, 14 figures, and 4 tables, accepted for publication in ApJ. Physical properties (e.g., BH mass, Eddington ratio, IR luminosity) of 37,181 quasars at z < 0.7 selected from the SDSS DR16 will be available as a Machine-readable table

We investigate the relation of black hole mass versus host stellar mass and that of mass accretion rate versus star formation rate (SFR) in moderately luminous ($\log L_{\rm bol} \sim 44.5-46.5\ {\rm erg\ s^{-1}}$), X-ray selected broad-line active galactic nuclei (AGNs) at $z=1.18-1.68$ in the Subaru/XMM-Newton Deep Field. The far-infrared to far-ultraviolet spectral energy distributions of 85 AGNs are reproduced with the latest version of Code Investigating GALaxy Emission ({\tt CIGALE}), where the AGN clumpy torus model {\tt SKIRTOR} is implemented. Most of their hosts are confirmed to be main-sequence star-forming galaxies. We find that the mean ratio of the black hole mass ($M_{\rm BH}$) to the total stellar mass ($M_{\rm stellar}$) is $\log M_{\rm BH}/M_{\rm stellar} = -2.2$, which is similar to the local black hole-to-bulge mass ratio. This suggests that if the host galaxies of these moderately luminous AGNs at $z\sim1.4$ are dominated by bulges, they already established the local black hole mass-bulge mass relation; if they are disk dominant, their black holes are overmassive relative to the bulges. AGN bolometric luminosities and SFR show a good correlation with ratios higher than that expected from the local black hole-to-bulge mass relation, suggesting that these AGNs are in a SMBH-growth dominant phase., Comment: 9 pages, 5 figures, 1 table, accepted for publication in ApJ; the error in the figure corrected, sentences changed a little