scholarly journals An outflow in the Seyfert ESO 362-G18 revealed by Gemini-GMOS/IFU observations

2018 ◽  
Vol 614 ◽  
pp. A94 ◽  
Author(s):  
Pedro K. Humire ◽  
Neil M. Nagar ◽  
Carolina Finlez ◽  
Verónica Firpo ◽  
Roy Slater ◽  
...  
Keyword(s):  
Galactic Disk ◽  
Position Angle ◽  
Morphological Type ◽  
Emission Lines ◽  
Stellar Kinematics ◽  
Mean Velocity ◽  
Gas Kinematics ◽  
Gaussian Fit ◽  
Kinematic Position ◽  
Integral Field Spectrograph

We present two-dimensional stellar and gaseous kinematics of the inner 0.7 × 1.2 kpc2 of the Seyfert 1.5 galaxy ESO 362-G18, derived from optical (4092–7338 Å) spectra obtained with the GMOS integral field spectrograph on the Gemini South telescope at a spatial resolution of ≈170 pc and spectral resolution of 36 km s−1. ESO 362-G18 is a strongly perturbed galaxy of morphological type Sa or S0/a, with a minor merger approaching along the NE direction. Previous studies have shown that the [O III] emission shows a fan-shaped extension of ≈10′′ to the SE. We detect the [O III] doublet, [N II] and Hα emission lines throughout our field of view. The stellar kinematics is dominated by circular motions in the galaxy plane, with a kinematic position angle of ≈137° and is centred approximately on the continuum peak. The gas kinematics is also dominated by rotation, with kinematic position angles ranging from 122° to 139°, projected velocity amplitudes of the order of 100 km s−1, and a mean velocity dispersion of 100 km s−1. A double-Gaussian fit to the [O III]λ5007 and Hα lines, which have the highest signal to noise ratios of the emission lines, reveal two kinematic components: (1) a component at lower radial velocities which we interpret as gas rotating in the galactic disk; and (2) a component with line of sight velocities 100–250 km s−1 higher than the systemic velocity, interpreted as originating in the outflowing gas within the AGN ionization cone. We estimate a mass outflow rate of 7.4 × 10−2 M⊙ yr−1 in the SE ionization cone (this rate doubles if we assume a biconical configuration), and a mass accretion rate on the supermassive black hole (SMBH) of 2.2 × 10−2 M⊙ yr−1. The total ionized gas mass within ~84 pc of the nucleus is 3.3 × 105 M⊙; infall velocities of ~34 km s−1 in this gas would be required to feed both the outflow and SMBH accretion.

scholarly journals Outflowing gas in a compact ionization cone in the Seyfert 2 galaxy ESO 153-G20

2019 ◽  
Vol 489 (3) ◽  
pp. 4111-4124 ◽  
Author(s):  
Pamela Soto-Pinto ◽  
Neil M Nagar ◽  
Carolina Finlez ◽  
Venkatessh Ramakrishnan ◽  
Dania Muñoz-Vergara ◽  
...  
Keyword(s):  
Major Axis ◽  
Position Angle ◽  
Emission Lines ◽  
Opening Angle ◽  
Stellar Kinematics ◽  
Velocity Amplitude ◽  
Gas Kinematics ◽  
Dispersion Component ◽  
Radiative Power ◽  
Field Unit

ABSTRACT We present two-dimensional ionized gas and stellar kinematics in the inner 1.4 × 1.9 kpc2 of the Seyfert 2 galaxy ESO 153-G20 obtained with the Gemini-South/Gemini multi-object spectrograph integral field unit (GMOS-IFU) at a spatial resolution of ~250 pc and spectral resolution of 36 km s−1. Strong [O iii], Hα, [N ii] and [S ii] emission lines are detected over the entire field of view. The stellar kinematics trace circular rotation with a projected velocity amplitude of ±96 km s−1, a kinematic major axis in position angle of 11°, and an average velocity dispersion of 123 km s−1. To analyse the gas kinematics, we used aperture spectra, position–velocity diagrams and single/double Gaussian fits to the emission lines. All lines show two clear kinematic components: a rotating component that follows the stellar kinematics, and a larger-dispersion component, close to the systemic velocity (from which most of the [O iii] emission comes), mainly detected to the south-west. We interpret this second component as gas outflowing at ∼400 km s−1 in a compact (300 pc) ionization cone with a half-opening angle ≤40°. The counter-cone is probably obscured behind a dust lane. We estimate a mass outflow rate of 1.1 M$\odot$ yr−1, 200 times larger than the estimated accretion rate on to the supermassive black hole, and a kinetic to radiative power ratio of 1.7 × 10−3. Bar-induced perturbations probably explain the remaining disturbances observed in the velocity field of the rotating gas component.

scholarly journals Panoramic Spectroscopy of Sy Galaxies with elongated radio structures

2006 ◽  
Vol 2 (S235) ◽  
pp. 136-136
Author(s):  
A. A. Smirnova ◽  
A. V. Moiseev
Keyword(s):  
Velocity Fields ◽  
Emission Lines ◽  
Stellar Kinematics ◽  
Active Nucleus ◽  
Ionized Gas ◽  
Fabry Perot ◽  
Gas Ionization ◽  
Integral Field Spectrograph ◽  
Ionizing Gas ◽  
Integral Field

AbstractWe have studied the ionized gas and stellar kinematics in several galaxies with active nuclei and elongated radio structures using 3D spectroscopy. The observations were performed at the SAO RAS 6-m telescope with the integral-field spectrograph MPFS (Afanasiev et al. 2001) and with a scanning Fabry-Perot interferometer (FPI) in the multimode device SCORPIO (Afanasiev & Moiseev 2005). Based on these data the intensity maps and velocity fields in the different emission lines of the ionizing gas were constructed. Using the lines-ratio diagrams we tried to search a source of the gas ionization: an active nucleus, hot young stars or shock waves.

scholarly journals Near-IR Integral Field Spectroscopy of the central region of NGC 5929

2014 ◽  
Vol 10 (S309) ◽  
pp. 339-339
Author(s):  
Rogemar A. Riffel ◽  
Thaisa Storchi-Bergmann ◽  
Rogério Riffel
Keyword(s):  
Emission Line ◽  
Near Infrared ◽  
Line Emission ◽  
Linear Structure ◽  
Emission Lines ◽  
Line Profiles ◽  
Gas Kinematics ◽  
Systemic Velocity ◽  
Integral Field Spectrograph ◽  
Integral Field

AbstractWe present two-dimensional (2D) near-infrared spectra of the inner 300×300 pc2 of the Seyfert 2 galaxy NGC 5929 at a spatial resolution of ~20 pc obtained with the Gemini Near infrared Integral Field Spectrograph (NIFS). We present 2D maps for the emission line flux distributions and kinematics and report the discovery of a linear structure ~300 pc in extent and of ~50 pc in width oriented perpendicular to the radio jet, showing broadened emission-line profiles.While over most of the field the emission-line profiles have full-widths-at-half-maximum (FWHM) of ~210 km/s, at a linear structure perpendicular do the radio jet the emission-line FWHMs are twice this value, and are due to two velocity components, one blueshifted and the other redshifted relative to the systemic velocity. We attribute these velocities to an outflow from the nucleus which is launched perpendicular to the radio jet. We reported the detection of this peculiar outflow in Riffel, Storchi-Bergmann & Riffel (2014a), where more details of the analysis can be found. Since, NGC 5929 has a Type 2 nucleus, this detection implies that: (1) both ionizing radiation and relativistic particles are escaping through holes in the torus perpendicular to the radio jet; and/or (2) the torus is also outflowing, as proposed by recent models of tori as winds from the outer parts of an accretion flow; or (3) the torus is absent in NGC 5929.At other locations the gas kinematics is dominated by rotation in a disk, although some evidences of interaction of the radio jet with the emitting gas are seen as a broadening of the line profiles at the locations of the radio structures.The flux distributions for the [P ii], [Fe ii], H i and H2 emission lines show that the line emission is more extended along the PA = 60/240^, extending to up to 1.5” to both sides of the nucleus, while to the perpendicular direction (PA = -30/150^) the emission is extended to 0.7” from the nucleus. The flux distributions of all emission lines show a good correlation with radio the radio structures, with the two peak of emission associated to the soutwestern and northeastern radio knots. Some differences are observed among distinct emission lines. While the [Fe ii] and H2 emission peak at the location of the soutwestern radio structure at 0.6” from the nucleus, the H i recombination lines present the their highest fluxes at the location of the northeastern radio hotspot at 0.5” from the nucleus. Another difference is that the H2 emission is less collimated than that for other lines, being more extended perpendicularly to the radio jet. A detailed analysis of the line emission and kinematics will be presented in Riffel, Storchi-Bergmann & Riffel (2014b).

scholarly journals Resolved Gas Kinematics in a Sample of Low-Redshift High Star-Formation Rate Galaxies

2016 ◽  
Vol 33 ◽  
Author(s):  
Mathew Varidel ◽  
Michael Pracy ◽  
Scott Croom ◽  
Matt S. Owers ◽  
Elaine Sadler
Keyword(s):  
Star Formation ◽  
Velocity Gradient ◽  
Velocity Dispersion ◽  
Star Formation Rate ◽  
Formation Rate ◽  
Local Effect ◽  
Line Of Sight ◽  
Mean Velocity ◽  
Gas Kinematics ◽  
Integral Field Spectroscopy

AbstractWe have used integral field spectroscopy of a sample of six nearby (z ~ 0.01–0.04) high star-formation rate ($\text{SFR} \sim 10\hbox{--}40$$\text{M}_\odot \text{ yr$^{-1}$}$) galaxies to investigate the relationship between local velocity dispersion and star-formation rate on sub-galactic scales. The low-redshift mitigates, to some extent, the effect of beam smearing which artificially inflates the measured dispersion as it combines regions with different line-of-sight velocities into a single spatial pixel. We compare the parametric maps of the velocity dispersion with the Hα flux (a proxy for local star-formation rate), and the velocity gradient (a proxy for the local effect of beam smearing). We find, even for these very nearby galaxies, the Hα velocity dispersion correlates more strongly with velocity gradient than with Hα flux—implying that beam smearing is still having a significant effect on the velocity dispersion measurements. We obtain a first-order non parametric correction for the unweighted and flux weighted mean velocity dispersion by fitting a 2D linear regression model to the spaxel-by-spaxel data where the velocity gradient and the Hα flux are the independent variables and the velocity dispersion is the dependent variable; and then extrapolating to zero velocity gradient. The corrected velocity dispersions are a factor of ~ 1.3–4.5 and ~ 1.3–2.7 lower than the uncorrected flux-weighted and unweighted mean line-of-sight velocity dispersion values, respectively. These corrections are larger than has been previously cited using disc models of the velocity and velocity dispersion field to correct for beam smearing. The corrected flux-weighted velocity dispersion values are σm ~ 20–50 km s−1.

scholarly journals 9.4. Nuclear gas kinematics of NGC 7052 and IC 1459 from HST/FOS spectra

1998 ◽  
Vol 184 ◽  
pp. 389-390
Author(s):  
Roeland P. van der Marel
Keyword(s):  
Black Holes ◽  
Emission Lines ◽  
Rotation Curves ◽  
Gas Kinematics

We have obtained HST/FOS measurements of the nuclear kinematics of the gas disks in NGC 7052 and IC 1459. The spectra show steeper rotation curves and broader emission lines than ground-based data. Detailed modeling is in progress to constrain the mass of possible black holes.

scholarly journals Study of the Gas Kinematics in the Center of the Barred Spiral Galaxy NGC 4258.

1996 ◽  
Vol 157 ◽  
pp. 164-167
Author(s):  
S. N. Dodonov
Keyword(s):  
Spiral Galaxy ◽  
Spatial Sampling ◽  
Kinematic Structure ◽  
Gas Kinematics ◽  
Barred Spiral Galaxy ◽  
Integral Field Spectrograph ◽  
Integral Field

AbstractIntegral Field Spectrograph observations of southeast (SE) gas outflow in the center (11×13 arcsec) of NGC 4258 with spatial sampling 0.6 and 1.2 arcsec were made with the 6-m Telescope. Reconstructed spatial and kinematic structure of the SE outflow from 20-30 pc to 200-220 pc are presented.

scholarly journals The Central Bar in M 94

1996 ◽  
Vol 171 ◽  
pp. 422-422
Author(s):  
C. Möllenhoff ◽  
M. Matthias ◽  
O.E. Gerhard
Keyword(s):  
Major Axis ◽  
Stellar Kinematics ◽  
Semi Major Axis ◽  
Ionized Gas ◽  
Model Calculations ◽  
Gas Kinematics ◽  
Closed Orbits ◽  
Total Light ◽  
Axis Length ◽  
Global And Local

Surface photometry in I, J, K of the oval disk galaxy M 94 (NGC 4736) reveal a weak central stellar bar of 0.7 kpc semi-major axis length, comprising ≈ 14% of the total light within 20″. By stellar kinematics the existence of a small spheroidal bulge with v/à ≈ 0.8 was discovered. The ionized gas (Hα) in this region shows global and local deviations from the stellar kinematics. Model calculations of closed orbits for the cold gas in the combined potential of bar, disk, and bulge predict large non-circular motions in equilibrium flow. However, these do not fit the observed gas kinematics; obviously hydrodynamical forces play a role in the central region of M 94.

Mapping the dark matter of NGC 2974: Combination of stellar & cold gas kinematics

2019 ◽  
Vol 14 (S353) ◽  
pp. 253-254
Author(s):  
M. Yang ◽  
L. Zhu ◽  
A. Weijmans ◽  
G. van de Ven ◽  
N. F. Boardman ◽  
...  
Keyword(s):  
Dark Matter ◽  
New Method ◽  
Stellar Kinematics ◽  
Gas Kinematics ◽  
Superposition Technique ◽  
Cold Gas

AbstractWe present a new method to combine cold gas kinematics with the stellar kinematics modelled with the Schwarzschild orbit-superposition technique, and its application to the lenticular galaxy NGC 2974. The combination of stellar and cold gas kinematics significantly improves the constraints on the measured dark matter profile: assuming a generalised NFW halo profile, we find a cuspy inner halo slope for NGC 2974.

scholarly journals The distant (z = 0.471) radiogalaxy 3C 435 A with the integral field spectrograph TIGER

1995 ◽  
Vol 149 ◽  
pp. 250-253
Author(s):  
B. Rocca-Volmerange ◽  
G. Adam ◽  
P. Ferruit ◽  
R. Bacon
Keyword(s):  
Energy Distribution ◽  
Galaxy Evolution ◽  
Large Degree ◽  
Emission Lines ◽  
Image Point ◽  
Redshift Galaxy ◽  
Stellar Energy ◽  
Integral Field Spectrograph ◽  
Intermediate Redshift ◽  
Integral Field

The distant radiogalaxies recently discovered at the most remote distances (z≥3.5) are among the best cosmological targets. However so various features caracterize these galaxies (red stellar energy distribution, huge emission lines, high density of galaxy companions, alignment of ultraviolet and radio axes, large degree of polarisation) that their structures are not simple to understand. Stellar populations will only become the best indicators of evolution of galaxies if these structures are clearly understood from a two-dimension spectroscopy on each image point. The integral field spectrograph TIGER is a unique instrument at the CFHT to give details on the nature and velocities of the various components of distant radiogalaxies.We present the observations with TIGER of an intermediate-redshift galaxy 3C435A (z=0.471) (Rocca-Volmerange et al, 1994). The two nebular lines [OII], [OIII] and the largely extended stellar continua are observable, allowing to date galaxy with the help of our evolution model. The present and past star formation activities and the origin of alignment will be thus analysed in terms of galaxy evolution.

scholarly journals The polarized signal from broad emission lines in AGNs

2019 ◽  
Vol 491 (1) ◽  
pp. 1-12 ◽  
Author(s):  
P Lira ◽  
R W Goosmann ◽  
M Kishimoto ◽  
R Cartier
Keyword(s):  
Active Galactic Nuclei ◽  
Galactic Nuclei ◽  
Position Angle ◽  
Emission Lines ◽  
Type I ◽  
Line Profiles ◽  
Scattering Media ◽  
Broad Emission ◽  
Line Region ◽  
Scattering Signal

ABSTRACT Using the stokes Monte Carlo radiative transfer code, we revisit the predictions of the spectropolarimetric signal from a disc-like broad emission line region (BLR) in type I active galactic nuclei due to equatorial scattering. We reproduce the findings of previous works, but only for a scatterer that is much more optically and geometrically thick than previously proposed. We also find that when taking into account the polarized emission from all regions of the scatterer, the swing of the polarization position angle (PA) is in the opposite direction to that originally proposed. Furthermore, we find that the presence of outflows in the scattering media can significantly change the observed line profiles, with the PA of the scattering signal being enhanced in the presence of radially outflowing winds. Finally, a characteristically different PA profile, shaped like an ‘M’, is seen when the scatterer is co-spatial with the BLR and radially outflowing.

Sign in / Sign up

Export Citation Format

Share Document