We present Atacama Large Millimeter/submillimeter Array observations of a radio-loud and millimeter-bright galaxy at z=2.6. Gravitational lensing by a foreground galaxy at z~0.2 provides access to physical scales of approximately 360 pc, and we resolve a 2.5 kpc-radius ring of star-forming molecular gas, traced by atomic carbon CI(1-0) and carbon monoxide CO(4-3). We also detect emission from the cyanide radical, CN(4-3). With a velocity width of 680 km/s, this traces dense molecular gas travelling at velocities nearly a factor of two larger than the rotation speed of the molecular ring. While this could indicate the presence of a dynamical and photochemical interaction between the active galactic nucleus and molecular interstellar medium on scales of a few 100 pc, on-going feedback is unlikely to have a significant impact on the assembly of stellar mass in the molecular ring, given the ~10s Myr depletion timescale due to star formation.
The active galactic nucleus (AGN) phenomena results from a supermassive black hole accreting its surrounding gaseous and dusty material. The infrared (IR) regime provides most of the information to characterize the dusty structures that bridge from the galaxy to the black hole, providing clues to the black hole growth and host galaxy evolution. Over the past several decades, with the commissioning of various ground, airborne and space IR observing facilities, our interpretations of the AGN circumnuclear structures have advanced significantly through improved understanding of how their dust emi…
We consider the circumnuclear regions of MaNGA galaxies. The spectra are classified as AGN-like, HII-region-like (or SF-like), and intermediate (INT) spectra according to their positions on the BPT diagram. There are the following four configurations of the radiation distributions in the circumnuclear regions: 1) AGN+INT, the innermost region of the AGN-like radiation is surrounded by a ring of radiation of the intermediate type; 2) INT, the central area of radiation of the intermediate type; 3) SF+INT, the inner region of the HII-region-like radiation is surrounded by a ring of radiation of t…
We studied the circumnuclear MIR emission in a sample of 19 local active galactic nuclei (AGN) with high spatial resolution spectra using T-ReCS (Gemini) and CanariCam (GTC), together with IRS/Spitzer observations. We measured the flux and the equivalent width for the 11.3 micron PAH feature and the [SIV] line emission as a function of galactocentric distance. This allowed to study the star formation (SF) at sub-kpc scales from the nucleus for a large sample of nearby AGN. The [SIV] line emission could be tracing the AGN radiation field within a few thousand times the sublimation radius (R_sub…
Young Star Clusters In The Circumnuclear Region Of NGC 2110
近红外高分辨率观测显示,在塞弗特1号NGC 2110的活动星系核(AGN)周围有星团,在其核周围有一个90 x 35 pc的冲击气体物质棒。这些都是第一次看到我们的成像和气体运动学的中央100 pc与凯克OSIRIS仪器与自适应光学。这些星团中的每一个都比靠近银河系中心的拱门星团亮2-3倍。核心恒星形成率(SFR)为0.3 M $_\odot$ /年。光电离气体(He I)动力学意味着封闭质量为3-4 x 10 $^8$ M $_\odot$。这些观测结果证明了活动星系核反馈(触发大质量星团中的恒星形成)与由此产生的恒星风(和SNe)之间的物理联系,后者导致观测到的[Fe II]发射并为黑洞提供能量。
We have analyzed the frequency and properties of the nuclear activity in a sample of galaxies with circumnuclear rings and spirals (CNRs). This sample was compared with a control sample of galaxies with very similar global properties but without circumnuclear rings. We discuss the relevance of the results in regard to the AGN feeding processes and present the following results: (i) bright companion galaxies seem not to be important for the appearance of CNRs, which appear to be more related to intrinsic properties of the host galaxies or to minor merger processes; (ii) the proportion of strong…
The host galaxy conditions for rapid supermassive black hole growth are poorly understood. Narrow-line Seyfert 1 (NLS1) galaxies often exhibit high accretion rates and are hypothesized to be prototypes of active galactic nuclei (AGN) at an early stage of their evolution. We present VLT MUSE NFM-AO observations of Mrk 1044, the nearest super-Eddington accreting NLS1. Together with archival MUSE WFM data we aim to understand the host galaxy processes that drive Mrk 1044's black hole accretion. We extract the faint stellar continuum emission from the AGN-deblended host and perform spatially resol…
NGC 7469 is a well known Luminous IR Galaxy, with a circumnuclear star formation ring ($\sim 830$ pc radius) surrounding a Seyfert 1 AGN. Nuclear unresolved winds were previously detected in X-rays and UV, as well as an extended biconical outflow in IR coronal lines. We search for extended outflows by measuring the kinematics of the $\mathrm{Hβ}$ and [O III] $λ5007$ optical emission lines, in data of the VLT/MUSE integral field spectrograph. We find evidence of two outflow kinematic regimes: one slower regime extending across most of the star formation ring -- possibly driven by the massive st…
A low-luminosity type-1 QSO sample: II. Tracing circumnuclear star formation in HE 1029-1831 with SINFONI
环核恒星的形成和活动星系核的反馈被认为在星系演化中起着关键作用。低光度类星体(LLQSO)样本包含99个最近的活动星系核,其红移z<=0.06,填补了活动星系核与高红移类星体之间的空白,这对于理解活动星系核的红移演化是必不可少的。本文给出了LLQSO HE 1029-1831近红外H+ K积分场谱的实验结果。线图显示电离的氢气位于恒星棒内的旋臂和环核环中。线通量和诊断线比率表明,最近或正在进行的恒星形成的环核区域和存在的年轻和中期年龄的恒星星族在隆起。特别是,我们在环核区域发现了强烈的星暴痕迹,它大约在1亿年前开始,但现在已经下降到最大强度的一小部分。我们估计了星系的动力学核球质量,发现该星系遵循已发表的M_BH-M_bulge关系。然而,用BUDDA对K波段图像进行的球盘分解表明,HE 1029-1831并不遵循不活跃星系的M_BH-L_bulge关系。我们的结论是,该源中不活动星系偏离M_BH-L_bulge关系的原因是年轻的恒星星族,而不是质量不足的黑洞。
We report a clumpy elongated feature found with deep Chandra ACIS high-resolution imaging of the Fe Kα line emission in the nuclear region of the Compton Thick Active Galactic Nucleus (CT AGN) galaxy NGC 5643. This feature extends for ~65 pc N-S. No corresponding feature is seen in the 3.0-6.0 keV continuum. The Fe Kα feature is spatially consistent with the N-S elongation found in the CO(2-1) high resolution imaging with ALMA (Alonso-Herrero et al 2018), but slightly more extended than the rotating molecular disk of r=26 pc indicated by the kinematics of the CO(2-1) line. The Chandra detectio…
We present the circumnuclear multi-phase gas properties of the brightest cluster galaxy (BCG) in the center of Abell 1644-South. A1644-S is the main cluster in a merging system, which is well known for X-ray hot gas sloshing in its core. The sharply peaked X-ray profile of A1644-S implies the presence of a strongly cooling gas core. In this study, we analyze ALMA CO (1-0) data, JVLA HI data, and KaVA 22 GHz data for the central region of A1644-S to probe the potential origin of the cool gas and its role in (re)powering the central active galactic nucleus (AGN). We find CO clumps distributed in…
The obscuring circumnuclear torus of dusty molecular gas is one of the major components of active galactic nuclei (AGN). The torus can be studied by analyzing the time response of its infrared (IR) dust emission to variations in the AGN continuum luminosity, a technique known as reverberation mapping. The IR response is the convolution of the AGN ultraviolet/optical light curve with a transfer function that contains information about the size, geometry, and structure of the torus. Here, we describe a new computer model that simulates the reverberation response of a clumpy torus. Given an input…
The size and structure of the dusty circumnuclear torus in active galactic nuclei (AGN) can be investigated by analyzing the temporal response of the torus's infrared (IR) dust emission to variations in the AGN ultraviolet/optical luminosity. This method, reverberation mapping, is applicable over a wide redshift range, but the IR response is sensitive to several poorly constrained variables relating to the dust distribution and its illumination, complicating the interpretation of measured reverberation lags. We have used an enhanced version of our torus reverberation mapping code (TORMAC) to c…
We present the results of the latest NuSTAR monitoring campaign of the Compton-thick Seyfert 2 galaxy NGC 1068, composed of four $\sim$50 ks observations performed between July 2017 and February 2018 to search for flux and spectral variability on timescales from 1 to 6 months. We detect one unveiling and one eclipsing event with timescales less than 27 and 91 days, respectively, ascribed to Compton-thick material with $N_H=(1.8\pm0.8)\times10^{24}$ cm$^{-2}$ and $N_H\geq(2.4\pm0.5)\times10^{24}$ cm$^{-2}$ moving across our line of sight. This gas is likely located in the innermost part of the …
We use Herschel data to analyze the size of the far-infrared 70micron emission for z<0.06 local samples of 277 hosts of Swift-BAT selected active galactic nuclei (AGN), and 515 comparison galaxies that are not detected by BAT. For modest far-infrared luminosities 8.5<log(LFIR)<10.5, we find large scatter of half light radii Re70 for both populations, but a typical Re70 <~ 1 kpc for the BAT hosts that is only half that of comparison galaxies of same far-infrared luminosity. The result mostly reflects a more compact distribution of star formation (and hence gas) in the AGN hosts, but compact AGN…
We used the Atacama Large Millimeter/Submillimeter Array (ALMA) to map the CO(3-2) and [CI](1-0) lines, as well as their underlying continuum emission, from the central $\sim 200$ pc region of the Circinus galaxy that hosts the nearest type 2 Seyfert-class active galactic nucleus (AGN), with a spatial resolution of $\sim 6-15$ pc. The lines and continuum-emitting regions consist of a circumnuclear disk (CND; 74 pc $\times$ 34 pc) and spiral arms. The distribution of the continuum emission revealed a temperature-dependent dust geometry and possibly polar dust elongation in the torus region. The…
This review summarises what we have learnt in the last two decades based on HI 21-cm absorption observations about the cold interstellar medium (ISM) in the central regions of active galaxies and the interplay between this gas and the active nucleus (AGN). HI absorption is a powerful tracer on all scales, from the pc scales to many tens of kpc. Given the strong radio continuum often associated with the central activity, HI absorption can be used to study the HI near an AGN out to much higher redshifts than is possible using HI emission. HI absorption has been used to characterise the general I…
Breaking the Blend: A multi-tracer kinematic decomposition method for IFS data applied to disentangling the AGN outflow and circumnuclear ring in NGC 5728 with JWST
NGC 6744 is the nearest and brightest south-hemisphere galaxy with a morphological type similar to that of the Milky Way. Using data obtained with the Integral Field Unit of the Gemini South Multi-Object Spectrograph, we found that this galaxy has a nucleus with LINER (Low Ionization Nuclear Emission Line Region) surrounded by three line emitting regions. The analysis of the Hubble Space Telescope archival images revealed that the nucleus is associated with a blue compact source, probably corresponding to the active galactic nucleus (AGN). The circumnuclear emission seems to be part of the ext…
We present deep dual-band 5.0 and 8.4GHz European VLBI Network (EVN) observations of NGC1614, a local luminous infrared galaxy with a powerful circumnuclear starburst ring, and whose nuclear engine origin is still controversial. We aim at detecting and characterizing compact radio structures both in the nuclear region and in the circumnuclear ring. We do not find any compact source in the central 200pc region, setting a very tight 5 sigma upper limit of $3.7\times10^{36}$erg s$^{-1}$ and $5.8\times10^{36}$erg s$^{-1}$, at 5.0 and 8.4GHz, respectively. However, we report a clear detection at bo…
In the nearby (D=14 Mpc) AGN-starburst composite galaxy NGC 1068, it has been found that the molecular gas in the Circum-nuclear Disk (CND) is outflowing, which is a manifestation of ongoing AGN feedback. The outflowing gas has a large spread of velocities, which likely drive different shock chemistry signatures at different locations in the CND. We perform a multi-line molecular study using two shock tracers, SiO and HNCO, with the aim to determine the gas properties traced by these two species, and explore the possibility of reconstructing the shock history in the CND. Five SiO transitions a…
We present the distribution and kinematics of the molecular gas in the circumnuclear disk (CND, 400 pc x 200 pc) of Centaurus A with resolutions of ~5 pc (0.3 arcsec) and shed light onto the mechanism feeding the Active Galactic Nucleus (AGN) using CO(3-2), HCO+(4-3), HCN(4-3), and CO(6-5) observations obtained with ALMA. Multiple filaments or streamers of tens to a hundred parsec scale exist within the CND, which form a ring-like structure with an unprojected diameter of 9 x 6 arcsec (162pc x 108pc) and a position angle PA = 155deg. Inside the nuclear ring, there are two leading and straight …
The accretion rates needed to fuel the central black hole in a galaxy can be achieved via viscous torques in thick disks and rings, which can be resolved by millimetre interferometry within the inner ~20pc of the active galaxy NGC1068 at comparable scales and sensitivity to single dish observations of the Circumnuclear Disk (CND) in the Galactic Center. To interpret observations of these regions and determine the physical properties of their gas distribution, we present a modelling effort that includes (i) a simple dynamical simulations involving partially inelastic collisions between disk gas…
It has been well established in the past decades that the central black hole masses of galaxies correlate with dynamical properties of their harbouring bulges. This notion begs the question of whether there are causal connections between the AGN and its immediate vicinity in the host galaxy. In this paper we analyse the presence of circumnuclear star formation in a sample of 15 AGN using mid-infrared observations. The data consist of a set of 11.3{\mm} PAH emission and reference continuum images, taken with ground based telescopes, with sub-arcsecond resolution. By comparing our star formation…
Dynamical black hole mass measurements in some gas-rich galaxy mergers indicate that they are overmassive relative to their host galaxy properties. Overmassive black holes in these systems present a conflict with the standard progression of galaxy merger - quasar evolution; an alternative explanation is that a nuclear concentration of molecular gas driven inward by the merger is affecting these dynamical black hole mass estimates. We test for the presence of such gas near the two black holes in NGC 6240 using long-baseline ALMA Band 6 observations (beam size 0"06 $\times$ 0"03 or 30 pc$\times$…
We report on our combined analysis of HST, VLT/MUSE, VLT/SINFONI, and ALMA observations of the local Seyfert 2 galaxy, NGC 5728 to investigate in detail the feeding and feedback of the AGN. The datasets simultaneously probe the morphology, excitation, and kinematics of the stars, ionized gas, and molecular gas over a large range of spatial scales (10 pc--10 kpc). NGC 5728 contains a large stellar bar which is driving gas along prominent dust lanes to the inner 1 kpc where the gas settles into a circumnuclear ring. The ring is strongly star forming and contains a substantial population of young…
The molecular circumnuclear disk (CND) in Centaurus A: A multi-transition CO and [CI] survey with Herschel, APEX, JCMT, and SEST
我们介绍了赫歇尔空间天文台以及SEST、JCMT和APEX对NGC 128(Centaurus~A)中心致密环核盘的新CO和C^o线测量结果。Cen A中心的CO阶梯与星暴星系或活动星系核的CO阶梯有很大的不同。此外,Cen A [CI]中心发射线的相对强度也比其它星系的强得多。在同一视线范围内,致密的环核盘(CND)的CO表面亮度明显高于伸展得多的薄盘(ETD)。我们的LVG和PDR/XDR模型表明,如果通过紫外光子加热,则大部分CND气体相对较冷(25 - 80 K)且密度不高(~ 300 cm^{-3}),尽管在CND和ETD中都存在一些密度高得多的气体,其密度约为30 000 cm^{-3}。最后,在CND中也有高激发、高密度相(但在ETD中没有),要么是极端PDR的形式,但更可能是XDR的形式。Cen A CND的总气体质量为8.4 x 10^{7} M(太阳),不确定系数为2。CO-H2转换系数为4 x 10^{20} K km/s,也在2倍以内。
Shock-driven heating in the circumnuclear star-forming regions of NGC 7582: Insights from JWST NIRSpec and MIRI/MRS spectroscopy
University of Oxford(牛津大学);European University Cyprus(塞浦路斯欧洲大学);Centro de Astrobiología (CAB), CSIC-INTA(西班牙国家科学技术研究委员会-国家航空航天技术研究所天体生物学中心);Instituto de Astrofísica de Canarias(加那利群岛天体物理研究所);Universidad de La Laguna(拉帕尔马大学);Universidad Complutense de Madrid(马德里康普顿斯大学)
We present high-resolution (0.17\arcsec $\times$ 0.14\arcsec) Atacama Large Millimeter/submillimeter Array (ALMA) observations of the CO\,(6-5) line, and 435\um\ dust continuum emission within a $\sim$9\arcsec $\times$ 9\arcsec\ area centered on the nucleus of the galaxy NGC\,5135. NGC\,5135 is a well-studied luminous infrared galaxy that also harbors a Compton-thick active galactic nucleus (AGN). At the achieved resolution of 48 $\times$ 40\,pc, the CO\,(6-5) and dust emissions are resolved into gas "clumps" along the symmetrical dust lanes associated with the inner stellar bar. The clumps ha…
We present subarcsecond resolution mid-infrared (MIR) images obtained with 8-10 m-class ground-based telescopes of a complete volume-limited (DL<40 Mpc) sample of 24 Seyfert galaxies selected from the Swift/BAT nine month catalog. We use those MIR images to study the nuclear and circumnuclear emission of the galaxies. Using different methods to classify the MIR morphologies on scales of ~400 pc, we find that the majority of the galaxies (75-83%) are extended or possibly extended and 17-25% are point-like. This extended emission is compact and it has low surface brightness compared with the nuc…
NGC 4945 harbors one of the nearest active galactic nuclei (AGN), which allows reaching high spatial resolution with the current observational facilities. The Seyfert 2 nucleus is deeply obscured by an edge-on disk with $A_V\sim14$, requiring infrared observations to study circumnuclear structures and the interstellar medium. In this work, we present an imaging and longslit spectroscopic study of the nuclear region with a spatial resolution of 6.5 pc, based on Flamingos-2 (F2) and T-ReCS data taken at the Gemini South observatory. We report sub-arcsecond photometric measurements of the nucleus…
We studied the absorption features of CO lines against the continuum originating from the heated dust in the obscuring tori around active galactic nuclei (AGNs). We investigated the formation of absorption lines corresponding to the CO rotational transitions using three-dimensional non-LTE line transfer simulations considering the dust thermal emission. As in Papers I--III of this series, we performed post-processed radiative transfer calculations using the "radiation-driven fountain model" (wada2016}, which yields a geometrically thick obscuring structure around the nucleus. This model is con…
Molecular Abundance of the Circumnuclear Region Surrounding an Active Galactic Nucleus in NGC 1068 based on Imaging Line Survey in the 3-mm Band with ALMA
COSMOS-3D: Dense Circumnuclear Gas across Black Hole Growth Phases at z ~ 3
Chinese Academy of Sciences South America Center for Astronomy, National Astronomical Observatories, CAS(中国科学院南美天文中心,国家天文台);School of Astronomy and Space Sciences, University of Chinese Academy of Sciences(中国科学院大学天文与空间科学学院);Departamento de Astronomía, Universidad de Chile(智利大学天文学系);Steward Observatory, University of Arizona(亚利桑那大学斯图尔德天文台);Harvard-Smithsonian Center for Astrophysics(哈佛-史密松天体物理中心);Kavli Institute for Astronomy and Astrophysics, Peking University(北京大学科维理天文与天体物理研究所)
Massive molecular gas has been discovered in giant elliptical galaxies at the centers of galaxy clusters. To reveal its role in active galactic nucleus (AGN) feedback in those galaxies, we construct a semianalytical model of gas circulation. This model especially focuses on the massive molecular gas (interstellar cold gas on a scale of ~ 10 kpc) and the circumnuclear disk (~< 0.5 kpc). We consider the destruction of the interstellar cold gas by star formation and the gravitational instability for the circumnuclear disk. Our model can reproduce the basic properties of the interstellar cold gas …
We investigate the properties of the ionized gas irradiated by an active galactic nucleus (AGN) based on our "radiation-driven fountain" model for the nearest type-2 Seyfert galaxy, the Circinus galaxy (Wada et al. 2016). We conducted "quasi-three dimensional" spectral analysis using the spectral synthesis code CLOUDY and obtained the surface brightness distributions of lines, such as H$α$, H$β$, [OIII], [NII], and [SII] for the central 16-parsec region. The ionized regions observed based on these lines show a conical morphology around the rotation axis, even if we do not phenomenologically po…
The nearby, luminous infrared galaxy (LIRG) NGC 7469 hosts a Seyfert nucleus with a circumnuclear star-forming ring and is thus the ideal local laboratory for investigating the starburst--AGN connection in detail. We present integral-field observations of the central 1.3 kpc region in NGC 7469 obtained with the JWST Mid-InfraRed Instrument. Molecular and ionized gas distributions and kinematics at a resolution of {\sim}100 pc over the 4.9 - 7.6μm region are examined to study gas dynamics influenced by the central AGN. The low-ionization [Fe II] λ5.34μm and [Ar II] λ6.99μm lines are bright on t…
A series of gravitational instabilities in a circumnuclear gas disk (CND) are required to trigger gas transport to a central supermassive black hole (SMBH) and ignite Active Galactic Nuclei (AGNs). A test of this scenario is to investigate whether an enhanced molecular gas mass surface density ($Σ_{\rm mol}$) is found in the CND-scale of quasars relative to a comparison sample of inactive galaxies. Here we performed sub-kpc resolution CO(2-1) observations with ALMA of four low-redshift ($z \sim 0.06$), luminous ($\sim 10^{45}$ erg s$^{-1}$) quasars with each matched to a different star-forming…