We present Br$γ$ emission line kinematics of the nuclear region of NGC 253, recently known to host a strong galactic wind that limits the global star formation of the galaxy. We obtained high-resolution long-slit spectroscopic data with PHOENIX at Gemini-South, positioning the slit on the nucleus Infrared Core (IRC), close to the nuclear disk major axis. The spatial resolution was 0.35"($\sim$6 pc) and the slit length 14"($\sim$240 pc). The spectral resolution was $\sim$74000, unprecedented high for galactic nuclei observations at $\sim$2.1$μ$m. The line profiles appear highly complex, with blue asymmetry up to 3.5'' away of the IRC, and red asymmetries further away to NE. Several Gaussian components are necessary to fit the profile, nevertheless a narrow and a wide ones predominate. The IRC presents kinematic widths above 700 kms$^{-1}$ (FWZI), and broad component FWHM$\sim$400 kms$^{-1}$, the highest detected in a nearby galaxy. At the IRC, the blue-shifted broad component displays a 90 km s$^{-1}$ bump in radial velocity distribution, a feature we previously detected in molecular gas kinematics. The narrow component velocity dispersion ($\sim$32 kms$^{-1}$) is within the expected for normal galaxies and LIRGs. Intermediate components (FWHM$\sim$150 kms$^{-1}$, red-shifted to NE, blue-shifted to SW) appear at some positions, as well as weaker blue (-215 kms$^{-1}$) and red line wings (+300 kms$^{-1}$). The IRC depicts a large broad vs. narrow line flux-ratio (F(B)/F(N)$\sim$1.35), and the broad component seems only comparable with those observed at very high star-forming rate galaxies. The results indicate that the IRC would be the main source of the galactic winds originated in the central region of NGC 253.
Small kinematically-decoupled stellar discs with scalelengths of a few tens of parsec are known to reside in the centre of galaxies. Different mechanisms have been proposed to explain how they form, including gas dissipation and merging of globular clusters. Using archival Hubble Space Telescope imaging and ground-based integral-field spectroscopy, we investigated the structure and stellar populations of the nuclear stellar disc hosted in the interacting SB0 galaxy NGC 1023. The stars of the nuclear disc are remarkably younger and more metal rich with respect to the host bulge. These findings …
We present detailed morphological, photometric, and stellar-kinematic analyses of the central regions of two massive, early-type barred galaxies with nearly identical large-scale morphologies. Both have large, strong bars with prominent inner photometric excesses that we associate with boxy/peanut-shaped (B/P) bulges; the latter constitute ~ 30% of the galaxy light. Inside its B/P bulge, NGC 4608 has a compact, almost circular structure (half-light radius R_e approx. 310 pc, Sérsic n = 2.2) we identify as a classical bulge, amounting to 12.1% of the total light, along with a nuclear star clust…
We present our analysis of the narrow emission lines produced in the plasma regions within the bright active galactic nucleus of NGC 4151, from an ORBYTS research-with-schools public engagement project. Our goal was to test whether the properties of these plasma regions changed between XMM- Newton observations spanning 15 years from 2000 to 2015, by measuring the outflow velocities and distances. From this study, we found that NGC 4151 has at least two to three plasma regions. There is no evidence of the outflowing wind properties changing as the velocities and distances are consistent through…
NGC4460 is an isolated lenticular galaxy, in which galactic wind has been earlier discovered as a gas outflow associated with circumnuclear regions of star formation. Using the results of observations in the Halpha line with the scanning Fabry-Perot interferometer on the SAO RAS 6-m telescope, we studied the kinematics of the ionized gas in this galaxy. The parameters of gas outflow from the plane of the galactic disk were refined within a simple geometric model. We show that it is impossible to characterize the wind by a fixed velocity value. Characteristic outflow velocities are within 30..8…
NGC 6240 is a luminous infrared galaxy in the local universe in the midst of a major merger. We analyze high-resolution interferometric observations of warm molecular gas using CO J = 3 - 2 and 6 - 5 in the central few kpc of NGC 6240 taken by the Atacama Large Millimeter Array. Using these CO line observations, we model the density distribution and kinematics of the molecular gas between the nuclei of the galaxies. Our models suggest that a disk model represents the data poorly. Instead, we argue that the observations are consistent with a tidal bridge between the two nuclei. We also observe …
We present results from high signal-to-noise optical spectropolarimetric observations of the Seyfert 1 galaxies NGC783 and Mrk509 in the 3500-7000 A range. We find complex structure in the polarized emission for both objects. In particular, Position Angle (PA) changes across the Balmer lines show a distinctive 'M'-shaped profile that had not been observed in this detail before, but could represent a common trait in Seyfert 1 galaxies. In fact, while this shape is observed in all Balmer lines in NGC3783, Mrk509 transitions into a 'M'-shaped PA profile for higher transitions lines. We have model…
We combine new (NGC 1275, NGC 4151, and NGC 5506) and previously published (Cygnus A, Mrk 231, and NGC 1068) sub-arcsecond resolution mid-infrared (MIR; 8-13 $μ$m) imaging- and spectro-polarimetric observations of six Seyfert galaxies using CanariCam on the 10.4-m Gran Telescopio CANARIAS. These observations reveal a diverse set of physical processes responsible for the nuclear polarization, and permit characterization of the origin of the MIR nuclear polarimetric signature of active galactic nuclei (AGN). For all radio quiet objects, we found that the nuclear polarization is low (<1 per cent)…
The Seyfert 2 galaxy NGC 5252 contains a recently identified ultra-luminous X-ray (ULX) source that has been suggested to be a possible candidate off-nuclear low-mass active galactic nucleus. We present follow-up optical integral-field unit observations obtained using GMOS on the Gemini-North telescope. In addition to confirming that the ionized gas in the vicinity of the ULX is kinematically associated with NGC 5252, the new observations reveal ordered motions consistent with rotation around the ULX. The close coincidence of the excitation source of the line-emitting gas with the position of …
Continuing with previous research (Camperi et al. 2011),new heliocentric radial velocity distributions are presented for the nearby galaxy NGC 253, obtained from the ionized hydrogen recombination line H-alpha. These distributions have been derived from long-slit spectroscopy for various position angles. It is also shown the heliocentric radial velocity distribution corresponding to part of the infrared data (ionized hydrogen recombination line Br-gamma) observed with the Phoenix spectrograph of the Gemini South Observatory. Sequential mapping with the long slit using this instrument will enab…
The composite galaxy NGC 4102 hosts a LINER nucleus and a starburst. We mapped NGC 4102 in the 12.8 micron line of [NeII], using the echelon spectrometer TEXES on the NASA IRTF, to obtain a data cube with 1.5" spatial and 25 km/s spectral, resolution. Combining near-infrared, radio, and the [NeII] data shows that the extinction to the starburst is substantial, more than 2 magnitudes at K band, and that the neon abundance is less than half solar. We find that the star formation in the nuclear region is confined to a rotating ring or disk of 4.3" (~300 pc) diameter, inside the Inner Lindblad Res…
We present a detailed study of the nuclear star clusters (NSCs) and massive black holes (BHs) of four of the nearest low-mass early-type galaxies: M32, NGC205, NGC5012, and NGC5206. We measure dynamical masses of both the BHs and NSCs in these galaxies using Gemini/NIFS or VLT/SINFONI stellar kinematics, Hubble Space Telescope (HST) imaging, and Jeans Anisotropic Models. We detect massive BHs in M32, NGC5102, and NGC5206, while in NGC205, we find only an upper limit. These BH mass estimates are consistent with previous measurements in M32 and NGC205, while those in NGC5102 and NGC5206 are esti…
We investigate the stellar and ionized gas kinematics, and stellar populations of NGC3182 galaxy using integral field spectrograph data from the Calar Alto Legacy Integral Field Area survey. We try to clarify the nature of the ring structure in NGC 3182. We find a negative stellar age gradient out to the ring, while [α/Fe] considerably enhanced in the ring. The stellar metallicity shows a smooth negative gradient. From the line ratio diagnostic diagrams, we confirm that NGC 3182 is a Seyfert galaxy from emission line flux ratio, while the gas in the inner ring is ionized mostly by young stars.…
We report the discoveries of a nuclear ring of diameter 10$\arcsec$ ($\sim$1.5 kpc) and a potential low luminosity active galactic nucleus (LLAGN) in the radio continuum emission map of the edge-on barred spiral galaxy NGC~5792. These discoveries are based on the Continuum Halos in Nearby Galaxies - an Expanded Very Large Array (VLA) Survey, as well as subsequent VLA observations of sub-arcsecond resolution. Using a mixture of H$α$ and 24 $μ$m calibration, we disentangle the thermal and non-thermal radio emission of the nuclear region, and derive a star formation rate (SFR) of $\sim 0.4~M_{\su…
The integrated properties of nuclear rings are correlated with their host galaxy's secular evolution and its dynamics, as well as with the formation and evolution of the ring's star cluster population(s). Here we present a new method to accurately measure the spectral energy distribution and current star-formation rate (SFR) of the nuclear ring in the barred spiral galaxy NGC 1512 based on high-resolution {\sl Hubble} and {\sl Spitzer Space Telescope} images. Image degradation does not have a significant negative effect on the robustness of the results. To obtain the ring's SFR for the period …
The detailed study of nuclear regions of galaxies is important because it can help understanding the active galactic nucleus (AGN) feedback mechanisms, the connections between the nuclei and their host galaxies, and ultimately the galaxy formation processes. We present the analysis of an optical data cube of the central region of the galaxy NGC 2442, obtained with the integral field unit (IFU) of the Gemini Multi-Object Spectrograph (GMOS). We also performed a multiwavelength analysis, with Chandra data, XMM--Newton and NuSTAR spectra, and Hubble Space Telescope (HST) images. The analysis reve…
Adaptive optics observations of the flattened nuclear star cluster in the nearby edge-on spiral galaxy NGC 4244 using the Gemini Near-Infrared Integral Field Spectrograph (NIFS) have revealed clear rotation. Using these kinematics plus 2MASS photometry we construct a series of axisymmetric two-component particle dynamical models with our improved version of NMAGIC, a flexible Chi^2-made-to-measure code. The models consist of a nuclear cluster disc embedded within a spheroidal particle population. We find a mass for the nuclear star cluster of M=1.6^+0.5_-0.2 x 10^7 M_sun within ~42.4 pc (2"). …
We report near-infrared integral field spectroscopic observations of the active galactic nucleus NGC 4151 with archive data from the NIFS-Gemini North Telescope. We have selected best-seeing observations ($\lesssim$0.3 arcsec) that, allied to our methodology of image processing techniques, show structures with spatial resolution comparable to those of the HST. The intricate outflow of NGC 4151 is revisited in light of the results found for NGC 1068, in a previous work, and a very similar dynamic is found: the low-velocity [Fe II] emission depicts the glowing walls of an hourglass structure, wh…
The formation of nuclear star clusters (NSCs) remains an open question. In this work, we use spatially resolved HST/STIS spectroscopic observations of three nearby NSCs (hosted by NGC 5102, NGC 5206, and NGC 205) to constrain their formation histories by exploring radial variations of the stellar populations within each cluster. Utilizing full-spectrum fitting, we find substantial age and metallicity gradients within the central 0."9 (16~pc) of the NSC in NGC 5102 where populations near the center are young/metal-rich (age ~400~Myr and [M/H] ~-0.4) and become older/metal-poor at larger radii (…
Most massive galaxies show emission lines that can be characterized as LINERs. To what extent this emission is related to AGNs or to stellar processes is still an open question. In this paper, we analysed a sample of such galaxies to study the central region in terms of nuclear and circumnuclear emission lines, as well as the stellar component properties. For this reason, we selected 10 massive ($σ$ > 200 km/s) nearby (d < 31 Mpc) galaxies and observed them with the IFU/GMOS (integral field unit/Gemini Multi-Object Spectrograph) spectrograph on the Gemini South Telescope. The data were analyse…
We study the velocity dispersion profiles of the nuclei of NGC 1326, 2685, 5273 and 5838 in the CO first overtone band. There is evidence for a black hole (BH) in NGC 1326 and 5838. Gas is seen flowing out of the nuclear region of NGC 5273. We put upper limits on the nuclear BHs responsible for its activity and that of NGC 2685.
We present interferometric observations of CO lines (12CO(1-0, 2-1) and 13CO(1-0, 2-1)) and dense gas tracers (HCN(1-0), HCO+(1-0), HNC(1-0) and HNCO(4-3)) in two nearby edge-on barred lenticular galaxies, NGC 4710 and NGC 5866, with most of the gas concentrated in a nuclear disc and an inner ring in each galaxy. We probe the physical conditions of a two-component molecular interstellar medium in each galaxy and each kinematic component by using molecular line ratio diagnostics in three complementary ways. First, we measure the ratios of the position-velocity diagrams of different lines, secon…
We present near-infrared ($H$- and $K$-band) integral-field observations of the inner $\sim$700pc of the active spiral galaxy NGC613, obtained with SINFONI on the Very Large Telescope. We use emission-line ratios to determine the dominant excitation mechanisms in different regions within our field-of-view, in particular the active nucleus and the star-forming circum-nuclear ring. Diagnostic diagrams involving [FeII] and H$_2$ fluxes indicate that the gas is not only photoionized by the AGN in the nucleus of NGC613, but also shock-heated. On the other hand, the emission line ratios measured in …
We present the analysis of the molecular gas in the nuclear regions of NGC 4968, NGC 4845, and MCG-06-30-15, with the help of ALMA observations of the CO(2-1) emission line. The aim is to determine the kinematics of the gas in the central (~ 1 kpc) region. We use the 3D-Based Analysis of Rotating Object via Line Observations ($^{3D}$BAROLO) and DiskFit softwares. Circular motions dominate the kinematics of the gas in the central discs, mainly in NGC 4845 and MCG-06-30-15, however there is a clear evidence of non-circular motions in the central ($\sim$ 1 kpc) region of NGC 4845 and NGC 4968. Th…
Very Long Baseline Interferometry Search for Nuclear Radio Continuum Emission in the Barred Spiral Galaxy NGC 7479
National Radio Astronomy Observatory（国家射电天文台）；Texas Tech University（德克萨斯理工大学）；Max-Planck-Institut für Radioastronomie（马克斯·普朗克射电天文研究所）；Space Telescope Science Institute（太空望远镜科学研究所）；Morehead State University（莫尔黑德州立大学）
A long slit spectrum from the barred galaxy NGC 1415 has been obtained with the 2.1m Guillermo Haro telescope in Cananea, Mexico at position angle 155d (EofN) and shows the kinematics of Na I D lines (in absorption) and Halpha, 6562.8 A, [NII] 6548 A, [NII] 6584 A, [SII] 6716 A, and [SII] 6731 A lines in emission from the central regions and the disk. Our previous Halpha continuum-free imaging of the central region showed mainly two central bright Halpha knots straddling the nucleus, and Halpha emission regions along the south-east and north-west inner spiral arms. Velocities of the Na I D abs…
We analyze optical data cubes of the nuclear regions of two late-type galaxies, NGC 908 and NGC 1187, obtained with the Integral Field Unit of the Gemini Multi-Object Spectrograph. Both data cubes show stellar structures consistent with double nuclei. The morphology of the line-emitting areas in the central region of NGC 1187 is also of a double nucleus, while the spatial morphology of the line-emitting areas in the data cube of NGC 908 is consistent with a circumnuclear asymmetric ring. The emission-line ratios of the nuclear spectra (and, actually, along the entire field of view) of both gal…
The blue compact dwarf galaxy NGC 5253 hosts a very young central starburst. The center contains intense radio thermal emission from a massive ultracompact H II region (or "supernebula") and two massive and very young super star clusters (SSCs), which are seen at optical and infrared wavelengths. The spatial correspondence between these three objects over an area of < 0.5 arcsec is very uncertain, and it is usually assumed that one of the optically-detected SSCs coincides with the supernebula. Using the Gaia Data Release 2 catalog, we improve the absolute astrometry of Hubble Space Telescope u…
With a substantial nuclear molecular gas reservoir and broad, high-velocity CO molecular line wings previously interpreted as an outflow, NGC 1266 is a rare SB$0$ galaxy. Previous analyses of interferometry, spectrally resolved low-$J$ CO emission lines, and unresolved high-$J$ emission lines have established basic properties of the molecular gas and the likely presence of an AGN. Here, new spectrally resolved CO $J = 5 - 4$ to $J = 8 - 7$ lines from {\it Herschel Space Observatory} HIFI observations are combined with ground-based observations and high-$J$ {\it Herschel} SPIRE observations to …
We present a spatially resolved stellar population study of the inner $\sim$200\,pc radius of NGC4303 based on near-infrared integral field spectroscopy with SINFONI/VLT at a spatial resolution of 40-80pc and using the STARLIGHT code. We found the distribution of the stellar populations presents a spatial variation, suggesting an age stratification. Three main structures stand out. Two nuclear blobs, one composed by young stars (t $\leq$ 50Myr) and one with intermediate-age stars (50Myr $<$ t $\leq$ 2Gyr) both shifted from the centre. The third one is an internal intermediate-age spiral arm-li…
We present ALMA Band 6 $^{12}$CO(2--1) line and rest-frame 232GHz continuum observations of the nearby Compton-thick Seyfert galaxy NGC5643 with angular resolutions 0.11-0.26arcsec (9-21pc). The CO(2--1) integrated line map reveals emission from the nuclear and circumnuclear region with a two-arm nuclear spiral extending 10arcsec on each side. The circumnuclear CO(2--1) kinematics can be fitted with a rotating disk, although there are regions with large residual velocities and/or velocity dispersions. The CO(2--1) line profiles of these regions show two different velocity components. One is as…
We present the results of near-infrared H- and K-band European Southern Observatory SINFONI integral field spectroscopy of the Seyfert galaxy NGC 1566. We investigate the central kpc of this nearby galaxy, concentrating on excitation conditions, morphology, and stellar content. NGC 1566 was selected from our NUGA (-south) sample and is a ringed, spiral galaxy with a stellar bar. We present emission and absorption line measurements in the central kpc of NGC 1566. Broad and narrow Brγ lines were detected. The detection of a broad Brγ component is a clear sign of a super-massive black hole in the…
We present new mid-infrared N-band spectroscopy and Q-band photometry of the local luminous infrared galaxy NGC1614, one of the most extreme nearby starbursts. We analyze the mid-IR properties of the nucleus (central 150 pc) and four regions of the bright circumnuclear (diameter~600 pc) star-forming (SF) ring of this object. The nucleus differs from the circumnuclear SF ring by having a strong 8-12 micron continuum (low 11.3 micron PAH equivalent width). These characteristics, together with the nuclear X-ray and sub-mm properties, can be explained by an X-ray weak active galactic nucleus (AGN)…
The blue compact dwarf galaxy NGC 5253 hosts a very young starburst containing twin nuclear star clusters, separated by a projected distance of 5 pc. One cluster (#5) coincides with the peak of the H-alpha emission and the other (#11) with a massive ultracompact H II region. A recent analysis of these clusters shows that they have a photometric age of 1+/-1 Myr, in apparent contradiction with the age of 3-5 Myr inferred from the presence of Wolf-Rayet features in the cluster #5 spectrum. We examine Hubble Space Telescope ultraviolet and Very Large Telescope optical spectroscopy of #5 and show …
We analyze an optical data cube of the nuclear region of NGC 3621, taken with the integral field unit of the Gemini Multi-object Spectrograph. We found that the previously detected central line emission in this galaxy actually comes from a blob, located at a projected distance of 2.14" +/- 0.08" (70.1 +/- 2.6 pc) from the stellar nucleus. Only diffuse emission was detected in the rest of the field of view, with a deficit of emission at the position of the stellar nucleus. Diagnostic diagram analysis reveals that the off-centered emitting blob has a Seyfert 2 spectrum. We propose that the line-…
We report Chandra observations of the Scd galaxy NGC 2139, which is known to host a recently formed (10^7.6 yrs) nuclear star cluster. The star cluster is undetected in X-rays, with an upper bound on 0.5-7 keV luminosity of L_X < 7.1 x 10^37 erg/s. This bound implies a bolometric accretion luminosity <0.3 percent of the Eddington luminosity for a black hole with the mass (approximately 3400 M_sun) expected from extrapolation of the M-sigma relation. The lack of X-ray emission indicates that a black hole, if present, is not undergoing significant accretion at the current time. While the central…
The recent ALMA maps together with observations of H$_2$O maser emission seem to suggest the presence of a counter-rotation in the obscuring torus of NGC 1068. We propose to explain this phenomenon as due to the influence of a wind, considered as radiation pressure, and the effects of torus orientation. In order to test this idea: 1. we make $N$-body simulation of a clumpy torus taking into account mutual forces between particles (clouds); 2. we apply ray-tracing algorithm with the beams from the central engine to choose the clouds in the torus throat that can be under direct influence of the …
The unusual behavior of the spectral lines of NGC5548 during the STORM campaign demonstrated a missing piece in the structure of AGNs. For a two-month period in the middle of the campaign, the spectral lines showed a deficit in flux and a reduced response to the variations of the UV continuum. This was the first time that this behavior was unequivocally observed in an AGN. Our previous papers explained this as being due to a variable disk-wind which acts as a shield and alters the SED. Here we use Cloudy to create an atlas of photoionization models for a variety of disk-winds to study their ef…
The merger remnant NGC 34 is a local luminous infrared galaxy (LIRG) hosting a nuclear starburst and a hard X-ray source associated with a putative, obscured Seyfert~2 nucleus. In this work, we use adaptive optics assisted near infrared (NIR) integral field unit observations of this galaxy to map the distribution and kinematics of the ionized and molecular gas in its inner $\mathrm{1.2\,kpc \times 1.2\,kpc}$, with a spatial resolution of 70~pc. The molecular and ionized gas kinematics is consistent with a disc with projected major axis along a mean PA~=~$\mathrm{-9^{\circ}.2 \pm 0^{\circ}.9}$.…
Galactic winds are associated with intense star formation and AGNs. Depending on their formation mechanism and velocity they may remove a significant fraction of gas from their host galaxies, thus suppressing star formation, enriching the intergalactic medium, and shaping the circumgalactic gas. However, the long-term evolution of these winds remains mostly unknown. We report the detection of a wind from NGC 3079 to at least 60 kpc from the galaxy. We detect the wind in FUV line emission to 60 kpc (as inferred from the broad FUV filter in GALEX) and in X-rays to at least 30~kpc. The morphology…
We present subarcsecond resolution infrared (IR) imaging and mid-IR spectroscopic observations of the Seyfert 1.9 galaxy NGC 2992, obtained with the Gemini North Telescope and the Gran Telescopio CANARIAS (GTC). The N-band image reveals faint extended emission out to ~3 kpc, and the PAH features detected in the GTC/CanariCam 7.5-13 micron spectrum indicate that the bulk of this extended emission is dust heated by star formation. We also report arcsecond resolution MIR and far-IR imaging of the interacting system Arp 245, taken with the Spitzer Space Telescope and the Herschel Space Observatory…
The under-abundance of very massive galaxies in the universe is frequently attributed to the effect of galactic winds. Although ionized galactic winds are readily observable most of the expelled mass is likely in cooler atomic and molecular phases. Expanding molecular shells observed in starburst systems such as NGC 253 and M 82 may facilitate the entrainment of molecular gas in the wind. While shell properties are well constrained, determining the amount of outflowing gas emerging from such shells and the connection between this gas and the ionized wind requires spatial resolution <100 pc cou…
A decade ago the archetypal Seyfert-1 galaxy NGC 5548 was discovered to have undergone major spectral changes. The soft X-ray flux had dropped by a factor of 30 while new broad and blueshifted UV absorption lines appeared. This was explained by the emergence of a new obscuring wind from the accretion disk. Here we report on the striking long-term variability of the obscuring disk wind in NGC 5548 including new observations taken in 2021-2022 with the Swift Observatory and the Hubble Space Telescope's (HST) Cosmic Origins Spectrograph (COS). The X-ray spectral hardening as a result of obscurati…
Super-massive black holes (SMBHs) spend most of their lifetime accreting at a rate well below the Eddington limit, manifesting themselves as low-luminosity active galactic nuclei (LLAGNs). The prevalence of a hot wind from LLAGNs is a generic prediction by theories and numerical simulations of black hole accretion and is recently becoming a crucial ingredient of AGN kinetic feedback in cosmological simulations of galaxy evolution. However, direct observational evidence for this hot wind is still scarce. In this work, we identify significant Fe XXVI Ly$α$ and Fe XXV K$α$ emission lines from hig…
Jet ejection by accreting black holes is a mass invariant mechanism unifying stellar and supermassive black holes (SMBHs) that should also apply for intermediate-mass black holes (IMBHs), which are thought to be the seeds from which SMBHs form. We present the detection of an off-nuclear IMBH of $\sim$5 $\times$ 10$^{4}$ M$_\odot$ located in an unusual spiral arm of the galaxy NGC 2276 based on quasi-simultaneous \textit{Chandra} X-ray observations and European VLBI Network (EVN) radio observations. The IMBH, NGC2276-3c, possesses a 1.8 pc radio jet that is oriented in the same direction as lar…
To understand the relation between the small "obscuring torus" and dusty structures at larger scales (5-10 pc) in NGC 1068, we use ESO's Mid-Infrared Interferometer (MIDI) with the 1.8 m Auxiliary Telescopes to achieve the necessary spatial resolution (~ 20-100 millarcsec). We use the chromatic phases in the data to improve the spatial fidelity of the analysis. We present interferometric data for NGC 1068 obtained in 2007 and 2012. We find no evidence of source variability. Many (u,v) points show non-zero chromatic phases indicating significant asymmetries. Gaussian model fitting of the correl…
The nearby low-luminosity active galactic nucleus (LLAGN) NGC 4258 has a weak radio continuum component at the galactic center. We investigate its radio spectral properties on the basis of our new observations using the Nobeyama Millimeter Array at 100 GHz and archival data from the Very Large Array (VLA) at 1.7-43 GHz and the James Clerk Maxwell telescope at 347 GHz. The NGC 4258 nuclear component exhibits (1) an intra-month variable and complicated spectral feature at 5-22 GHz and (2) a slightly inverted spectrum at 5-100 GHz (a spectral index of ~0.3) in time-averaged flux densities, which …
Winds of Change: XRISM Resolve X-ray spectroscopy of NGC 4051
The Catholic University of America（美国天主教大学）；INAF, Osservatorio Astronomico di Brera（意大利国家天体物理研究所布里拉天文台）；Università di Trento（特伦托大学）；Institute of Space and Astronautical Science (ISAS), Japan Aerospace Exploration Agency (JAXA)（日本宇宙航空研究开发机构宇宙科学研究所）；Eureka Scientific, Inc.（尤里卡科学公司）；The Frontier Research Institute for Interdisciplinary Sciences, Tohoku University（东北大学前沿交叉科学研究院）；Astronomical Institute, Tohoku University（东北大学天文学研究所）
