scholarly journals 2MASX J00423991 + 3017515: an offset active galactic nucleus in an interacting system

2021 ◽  
Vol 503 (2) ◽  
pp. 1688-1702
Author(s):  
J Drew Hogg ◽  
Laura Blecha ◽  
Christopher S Reynolds ◽  
Krista Lynne Smith ◽  
Lisa M Winter
Keyword(s):  
Active Galactic Nucleus ◽  
Hubble Space Telescope ◽  
Line Emission ◽  
Imaging Study ◽  
Host Galaxy ◽  
Strong Wind ◽  
X Rays ◽  
Disc Galaxy ◽  
Very Large Array ◽  
Three Body

ABSTRACT We present a spectroscopic and imaging study of an abnormal active galactic nucleus (AGN), 2MASX J00423991 + 3017515. This AGN is newly identified in the hard X-rays by the Swift BAT All-Sky survey and found in an edge-on disc galaxy interacting with a nearby companion. Here, we analyse the first optical spectra obtained for this system (taken in 2011 and 2016), high-resolution imaging taken with the Hubble Space Telescope and Chandra X-ray Observatory, and 1 imaging with the Very Large Array. Two unique properties are revealed: the peaks of the broad Balmer emission lines (associated with gas orbiting very near the supermassive black hole) are blueshifted from the corresponding narrow line emission and host galaxy absorption by 1540 km s−1, and the AGN is spatially displaced from the apparent centre of its host galaxy by 3.8 kpc. We explore several scenarios to explain these features, along with other anomalies, and propose that 2MASX J00423991 + 3017515 may be an AGN with an unusually strong wind residing in a uniquely configured major merger, or that it is an AGN recoiling from either a gravitational ‘slingshot’ in a three-body interaction or from a kick due to the asymmetric emission of gravitational waves following the coalescence of two progenitor supermassive black holes.

scholarly journals MORPHO-KINEMATICS OF THE MOLECULAR GAS IN A QUASAR HOST GALAXY AT REDSHIFT z=0.654

2020 ◽  
Vol 31 ◽  
Author(s):  
Thai Thi Tran ◽  
Tuan-Anh Pham ◽  
Pierre Darriulat ◽  
Hoai Thi Do ◽  
Nhung Tuyet Pham ◽  
...  
Keyword(s):  
Line Width ◽  
Complex Dynamics ◽  
Hubble Space Telescope ◽  
Hot Spot ◽  
Line Emission ◽  
Polar Coordinates ◽  
Host Galaxy ◽  
Doppler Velocity ◽  
Rotating Disc ◽  
Disc Model

e present a new study of archival ALMA observations of the CO(2-1) line emission ofthe host galaxy of quasar RX J1131. The quasar, at redshift z S ∼0.654, is lensed by a foreground galaxy at z L ∼0.30. Particular attention is paid to the mechanism of gravitational lensing. A simple lens model, shown to well reproduce the optical images obtained by the Hubble Space Telescope, is applied to the ALMA CO(2-1) images, providing a tool to understand the uncertainties attached to the evaluation of the source brightness and kinematics. Uncertainties attached to the process of data reduction are carefully evaluated. Evidence for the robustness of previously published results is obtained. A system of polar coordinates is introduced to better match the specificity ofthe imaging process. It provides particularly clear evidence for rotation of the gas contained in the galaxy. A simple rotating disc model is shown to give an excellent overall description of the morpho-kinematics of the source. It gives evidence for a hot spot of emission located near the quasar, overlapping the caustic and corresponding to an enhancement of emission by a factor ∼2.5. The possible presence of a companion galaxy suggested by some previous authors is not confirmed. The rotation curve is studied with reference to the predictions of the disc model. De-tailed comparison between model and observations gives evidence for a more complex dynamics than implied by the model. Doppler velocity dispersion within the beam size in the image plane is found to contribute 60±10 km s −1 to the line width. It accounts for the observed line width when a2- σ cut is applied to the data. However, when using a less severe cut, a significant amount of turbulence may be accommodated, preventing a reliable evaluation of the contribution of turbulence to the line width.

scholarly journals PHANGS–ALMA: Arcsecond CO(2–1) Imaging of Nearby Star-forming Galaxies

2021 ◽  
Vol 257 (2) ◽  
pp. 43
Author(s):  
Adam K. Leroy ◽  
Eva Schinnerer ◽  
Annie Hughes ◽  
Erik Rosolowsky ◽  
Jérôme Pety ◽  
...  
Keyword(s):  
Hubble Space Telescope ◽  
Formation Rate ◽  
Sample Selection ◽  
Line Emission ◽  
Nearby Star ◽  
Very Large Array ◽  
Star Forming ◽  
Very Large Telescope ◽  
Public Data ◽  
Cold Star

Abstract We present PHANGS–ALMA, the first survey to map CO J = 2 → 1 line emission at ∼1″ ∼100 pc spatial resolution from a representative sample of 90 nearby (d ≲ 20 Mpc) galaxies that lie on or near the z = 0 “main sequence” of star-forming galaxies. CO line emission traces the bulk distribution of molecular gas, which is the cold, star-forming phase of the interstellar medium. At the resolution achieved by PHANGS–ALMA, each beam reaches the size of a typical individual giant molecular cloud, so that these data can be used to measure the demographics, life cycle, and physical state of molecular clouds across the population of galaxies where the majority of stars form at z = 0. This paper describes the scientific motivation and background for the survey, sample selection, global properties of the targets, Atacama Large Millimeter/submillimeter Array (ALMA) observations, and characteristics of the delivered data and derived data products. As the ALMA sample serves as the parent sample for parallel surveys with MUSE on the Very Large Telescope, the Hubble Space Telescope, AstroSat, the Very Large Array, and other facilities, we include a detailed discussion of the sample selection. We detail the estimation of galaxy mass, size, star formation rate, CO luminosity, and other properties, compare estimates using different systems and provide best-estimate integrated measurements for each target. We also report the design and execution of the ALMA observations, which combine a Cycle 5 Large Program, a series of smaller programs, and archival observations. Finally, we present the first 1″ resolution atlas of CO emission from nearby galaxies and describe the properties and contents of the first PHANGS–ALMA public data release.

scholarly journals The OH Megamaser galaxy IRAS11506−3851: an AGN and star formation revealed by multiwavelength observations

2020 ◽  
Vol 498 (2) ◽  
pp. 2632-2644
Author(s):  
C Hekatelyne ◽  
Rogemar A Riffel ◽  
Thaisa Storchi-Bergmann ◽  
Preeti Kharb ◽  
Andrew Robinson ◽  
...  
Keyword(s):  
Active Galactic Nucleus ◽  
Velocity Dispersion ◽  
Hubble Space Telescope ◽  
Present Stage ◽  
Low Velocity ◽  
Very Large Array ◽  
Star Forming ◽  
Star Forming Regions ◽  
Field Unit ◽  
Integral Field

ABSTRACT We present Gemini Multi-Object Spectrograph (GMOS) Integral Field Unit (IFU), Hubble Space Telescope (HST), and Very Large Array (VLA) observations of the OH Megamaser (OHM) galaxy IRAS 11506−3851. The HST images reveal an isolated spiral galaxy and the combination with the GMOS-IFU flux distributions and VLA data allow us to identify a partial ring of star-forming regions surrounding the nucleus with a radius of ≈ 500 pc. While this ring shows starburst excitation and low velocity dispersion, the region internal to the ring shows higher excitation and velocity dispersion values, with values increasing towards its borders at ≈ 240 pc from the nucleus, resembling a projected bubble. The enhanced excitation and velocity dispersion of this bubble surrounds a 8.5-GHz radio emission structure, supporting its origin in a faint active galactic nucleus (AGN) that is mostly shocking the surrounding gas via a plasma ejection seen in radio at the present stage. This is the fourth of the 5 OHM galaxies we have studied so far (from our sample of 15 OHM) for which GMOS-IFU data indicate the presence of a previously unknown faint AGN at the nucleus, consistent with the hypothesis that OHM galaxies harbour recently triggered AGN.

scholarly journals Multiwavelength observations of the triple-peaked AGN Mrk 622

2019 ◽  
Vol 490 (4) ◽  
pp. 5521-5537
Author(s):  
E Benítez ◽  
I Cruz-González ◽  
J M Rodríguez-Espinosa ◽  
O González-Martín ◽  
C A Negrete ◽  
...  
Keyword(s):  
Hubble Space Telescope ◽  
Galactic Nuclei ◽  
Host Galaxy ◽  
Emission Region ◽  
Mid Infrared ◽  
Very Large Array ◽  
The Core ◽  
Spatially Resolved ◽  
Multiple Components ◽  
Line Region

ABSTRACT A detailed multiwavelength study of the properties of the triple-peaked active galactic nucleus (AGN) Mrk 622 showing different aspects of the nuclear emission region is presented. Radio, near- and mid-infrared, optical, and X-ray data have been considered for the analysis. In the optical, the WHAN diagnostic diagrams show that the three nuclear peaks are strong active galactic nuclei since the equivalent width of H α is > 6 Å  and log  [N ii] λ6584/H α  ratio is > −0.4. Optical variability of both the continuum flux and intensity of the narrow emission lines is detected in a time span of 13 yr. The size of the narrow-line region is found to be 2.7 pc, with a light-crossing time of 8.7 yr. Analysis done to an archival Hubble Space Telescope image at 1055.2 nm shows that the host galaxy has a 3.6 kpc inner bar with PA  =  74°, faint spiral arms, and a pseudobulge, evolving through secular processes. High-resolution mid-infrared images obtained with the Gran Telescopio Canarias (GTC) and the instrument CanariCam show that the nuclear emission at 11.6 $\rm{\mu m}$ is not spatially resolved. Very Large Array archival observations at 10 GHz reveal a core source with a total flux density of 1.47 ± 0.03 mJy. The spectral index of the core between 8 and 12 GHz is −0.5 ± 0.2, characteristic of AGN. The core deconvolves into a source with dimensions of 82 ± 13 mas $\, \times \,$ 41 ± 20 mas, and a PA = 70  ±  18 deg, which suggests that the core is elongated or that it is constituted by multiple components distributed along a ∼65° axis.

scholarly journals A nearby luminous AGN sample optically selected from Hubble Space Telescope

2019 ◽  
Vol 490 (3) ◽  
pp. 3793-3798 ◽  
Author(s):  
Shuang-Liang Li
Keyword(s):  
Active Galactic Nucleus ◽  
Very Long Baseline Interferometry ◽  
Hubble Space Telescope ◽  
Radio Flux ◽  
Space Telescope ◽  
Very Large Array ◽  
X Ray ◽  
Long Baseline ◽  
Very Long Baseline Array ◽  
The Relationship

ABSTRACT In this work, a nearby luminous active galactic nucleus (AGN) sample is selected from Hubble Space Telescope(HST), where only sources with both X-ray emission observed by Chandra/XMM–Newton and radio flux detected by Very Large Array (VLA)/Very Long Baseline Array (VLBA)/very long baseline interferometry (VLBI)/Multi-Element Radio Linked Interferometer Network (MERLIN) are adopted to keep high precision. Finally, we get a sample of 30 luminous AGNs, which consists of 11 radio-loud AGNs (RLAGN) and 19 radio-quiet AGNs (RQAGN). It is found that the relationship between RUV and αox, which was first reported by Li & Xie in low-luminosity AGNs (LLAGN), and other relationships are all absent in RLAGN, probably due to the complex physical process therein. Our results indicate that the X-ray emission from jet should play an important role in RLAGN and further support the transition of accretion mode between LLAGN and RLAGN. On the other hand, the traditional relationships in RQAGN, such as αox and λ, Γ and λ, are found to be well consistent with previous works.

scholarly journals The ultraluminous X-ray source bubble in NGC 5585

2020 ◽  
Vol 501 (2) ◽  
pp. 1644-1662
Author(s):  
R Soria ◽  
M W Pakull ◽  
C Motch ◽  
J C A Miller-Jones ◽  
A D Schwope ◽  
...  
Keyword(s):  
Supernova Remnants ◽  
Hubble Space Telescope ◽  
Line Emission ◽  
Optical Emission ◽  
Shock Velocity ◽  
Mechanical Power ◽  
Very Large Array ◽  
X Ray ◽  
Recent Addition ◽  
Collisional Ionization

ABSTRACT Some ultraluminous X-ray sources (ULXs) are surrounded by collisionally ionized bubbles, larger and more energetic than supernova remnants: they are evidence of the powerful outflows associated with super-Eddington X-ray sources. We illustrate the most recent addition to this class: a huge (350 pc × 220 pc in diameter) bubble around a ULX in NGC 5585. We modelled the X-ray properties of the ULX (a broadened-disc source with LX ≈ 2–4 × 1039 erg s−1) from Chandra and XMM–Newton, and identified its likely optical counterpart in Hubble Space Telescope images. We used the Large Binocular Telescope to study the optical emission from the ionized bubble. We show that the line emission spectrum is indicative of collisional ionization. We refine the method for inferring the shock velocity from the width of the optical lines. We derive an average shock velocity ≈125 km s−1, which corresponds to a dynamical age of ∼600 000 yr for the bubble, and an average mechanical power Pw ∼ 1040 erg s−1; thus, the mechanical power is a few times higher than the current photon luminosity. With Very Large Array observations, we discovered and resolved a powerful radio bubble with the same size as the optical bubble, and a 1.4-GHz luminosity ∼1035 erg s−1, at the upper end of the luminosity range for this type of source. We explain why ULX bubbles tend to become more radio luminous as they expand while radio supernova remnants tend to fade.

Improving x-ray map resolution with image restoration techniques

1996 ◽  
Vol 54 ◽  
pp. 598-599
Author(s):  
Richard B. Mott ◽  
John J. Friel ◽  
Charles G. Waldman
Keyword(s):  
Image Restoration ◽  
Hubble Space Telescope ◽  
Extensive Literature ◽  
Small Object ◽  
X Rays ◽  
X Ray ◽  
Mapping Parameters ◽  
The Matrix ◽  
The 1960S ◽  
Map Resolution

X-rays are emitted from a relatively large volume in bulk samples, limiting the smallest features which are visible in X-ray maps. Beam spreading also hampers attempts to make geometric measurements of features based on their boundaries in X-ray maps. This has prompted recent interest in using low voltages, and consequently mapping L or M lines, in order to minimize the blurring of the maps.An alternative strategy draws on the extensive work in image restoration (deblurring) developed in space science and astronomy since the 1960s. A recent example is the restoration of images from the Hubble Space Telescope prior to its new optics. Extensive literature exists on the theory of image restoration. The simplest case and its correspondence with X-ray mapping parameters is shown in Figures 1 and 2.Using pixels much smaller than the X-ray volume, a small object of differing composition from the matrix generates a broad, low response. This shape corresponds to the point spread function (PSF). The observed X-ray map can be modeled as an “ideal” map, with an X-ray volume of zero, convolved with the PSF. Figure 2a shows the 1-dimensional case of a line profile across a thin layer. Figure 2b shows an idealized noise-free profile which is then convolved with the PSF to give the blurred profile of Figure 2c.

scholarly journals Testing the evolution of correlations between supermassive black holes and their host galaxies using eight strongly lensed quasars

2020 ◽  
Vol 501 (1) ◽  
pp. 269-280
Author(s):  
Xuheng Ding ◽  
Tommaso Treu ◽  
Simon Birrer ◽  
Adriano Agnello ◽  
Dominique Sluse ◽  
...  
Keyword(s):  
Black Holes ◽  
Hubble Space Telescope ◽  
High Redshift ◽  
Galactic Nuclei ◽  
Host Galaxy ◽  
Wide Field ◽  
Host Galaxies ◽  
Field Surveys ◽  
Instrumental Resolution ◽  
The Moment

ABSTRACT One of the main challenges in using high-redshift active galactic nuclei (AGNs) to study the correlations between the mass of a supermassive black hole ($\mathcal {M}_{\rm BH}$) and the properties of its active host galaxy is instrumental resolution. Strong lensing magnification effectively increases instrumental resolution and thus helps to address this challenge. In this work, we study eight strongly lensed AGNs with deep Hubble Space Telescope imaging, using the lens modelling code lenstronomy to reconstruct the image of the source. Using the reconstructed brightness of the host galaxy, we infer the host galaxy stellar mass based on stellar population models. $\mathcal {M}_{\rm BH}$ are estimated from broad emission lines using standard methods. Our results are in good agreement with recent work based on non-lensed AGNs, demonstrating the potential of using strongly lensed AGNs to extend the study of the correlations to higher redshifts. At the moment, the sample size of lensed AGNs is small and thus they provide mostly a consistency check on systematic errors related to resolution for non-lensed AGNs. However, the number of known lensed AGNs is expected to increase dramatically in the next few years, through dedicated searches in ground- and space-based wide-field surveys, and they may become a key diagnostic of black holes and galaxy co-evolution.

Multiwavelength analysis of OH Megamaser galaxies: The case of IRAS11506-3851

2020 ◽  
Vol 15 (S359) ◽  
pp. 347-349
Author(s):  
Carpes P. Hekatelyne ◽  
Thaisa Storchi-Bergmann
Keyword(s):  
Active Galactic Nuclei ◽  
Hubble Space Telescope ◽  
Galactic Nuclei ◽  
Large Array ◽  
Very Large Array ◽  
Star Forming ◽  
Star Forming Regions ◽  
Field Unit ◽  
Mixed Transition ◽  
Integral Field

AbstractWe present Multi-Object Spectrograph (GMOS) Integral Field Unit (IFU), Hubble Space Telescope (HST) and Very Large Array (VLA) observations of the inner kpc of the OH Megamaser galaxy IRAS 11506-3851. In this work we discuss the kinematics and excitation of the gas as well as its radio emission. The HST images reveal an isolated spiral galaxy and the combination with the GMOS-IFU flux distributions allowed us to identify a partial ring of star-forming regions surrounding the nucleus with a radius of ≍500 pc. The emission-line ratios and excitation map reveal that the region inside the ring present mixed/transition excitation between those of Starbursts and Active Galactic Nuclei (AGN), while regions along the ring are excited by Starbursts. We suggest that we are probing a buried or fading AGN that could be both exciting the gas and originating an outflow.

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