scholarly journals Physical properties of the nuclear region in Seyfert galaxies derived from EVN observations

2016 ◽  
Author(s):  
Marcello Giroletti ◽  
Francesca Panessa ◽  
Monica Orienti ◽  
Akihiro Doi
Keyword(s):  
Physical Properties ◽  
Seyfert Galaxies ◽  
Nuclear Region

scholarly journals Physical Properties of the Extranuclear Emitting Regions in Irregular and Interacting AGNs

1989 ◽  
Vol 134 ◽  
pp. 478-479
Author(s):  
P. Rafanelli
Keyword(s):  
Physical Properties ◽  
Power Law ◽  
Seyfert Galaxies ◽  
Photon Spectrum ◽  
H Ii Regions ◽  
Hard Photon ◽  
Scattering Of Light ◽  
Shock Heating ◽  
Thermal Sources

CCD slit spectra have been obtained at Lick Observatory of a sample of fourteen close interacting and irregular Seyfert galaxies. The spectra of the extranuclear emitting regions have been investigated and classified using the quantitative criteria recommended by Veilleux and Osterbrock to distinguish objects photoionized by thermal sources from objects photoionized by a “power law” continuum. From our data it results that four out of the twenty emitting regions identified are typical H II regions, while eight have spectra photoionized by a hard-photon spectrum. Seven regions show a twofold behavior which is interpreted in terms of a combination of photoionization, shock heating and scattering of light by dust.

scholarly journals Physical properties of dense molecular gas in centres of Seyfert galaxies

2012 ◽  
Vol 424 (3) ◽  
pp. 1963-1976 ◽  
Author(s):  
E. Sani ◽  
R. I. Davies ◽  
A. Sternberg ◽  
J. Graciá-Carpio ◽  
E. K. S. Hicks ◽  
...  
Keyword(s):  
Physical Properties ◽  
Seyfert Galaxies ◽  
Molecular Gas

scholarly journals The Coronal Emission-Line Region in AGNs: A Hubble Space Telescope View

2009 ◽  
Vol 5 (S267) ◽  
pp. 122-122
Author(s):  
X. Mazzalay ◽  
A. Rodríguez-Ardila ◽  
S. Komossa
Keyword(s):  
Physical Properties ◽  
Spatial Resolution ◽  
High Spatial Resolution ◽  
Hubble Space Telescope ◽  
Seyfert Galaxies ◽  
Coronal Line ◽  
Coronal Emission ◽  
Line Region ◽  
High Ionization ◽  
Coronal Emission Line

AbstractWe present a study of HST/STIS optical spectra of a sample of ten Seyfert galaxies aimed at analyzing the structure and physical properties of the coronal line region. The high spatial resolution provided by STIS (about 7 pc for the closest objects) allowed us to resolve the coronal line region and obtain key information about the kinematics of the coronal-line gas, measure directly its spatial scale, and study the mechanisms that drive the high-ionization lines.

scholarly journals Molecular gas kinematics in the nuclear region of nearby Seyfert galaxies with ALMA

2021 ◽  
Author(s):  
A. Bewketu Belete ◽  
P. Andreani ◽  
J. A. Fernández-Ontiveros ◽  
E. Hatziminaoglou ◽  
F. Combes ◽  
...  
Keyword(s):  
Seyfert Galaxies ◽  
Molecular Gas ◽  
Nuclear Region ◽  
Gas Kinematics

scholarly journals Luminous Supernova Remnant Candidates in M82 and The Physical Properties of The Variable Radio Source 41.9+58

1983 ◽  
Vol 101 ◽  
pp. 583-590 ◽  
Author(s):  
P. P. Kronberg ◽  
P. Biermann
Keyword(s):  
Physical Properties ◽  
Radio Source ◽  
Supernova Remnant ◽  
Low Frequency ◽  
Nuclear Region ◽  
Large Numbers ◽  
Relativistic Particles ◽  
Bright Source ◽  
Variable Radio ◽  
Variable Radio Source

Large numbers (∼30) of supernova remnant candidates have been revealed in new VLA maps of the inner 600 pc of M82 with subarcsecond resolution. The flux density decrease of the bright source 41.9+58 in the M82 nuclear region is found to be occurring with an approximately constant spectral index of −0.9 at ν≳3 GHz, and the low frequency turnover has moved from ∼700 MHz in 1974–1975 to <400 MHz in 1979–81.A model of 41.9+58 is proposed in which it is, at least initially confined by its own hot (∼108K) pre-SN ejecta, and its relativistic particles are accelerated by a pulsar at its centre.

X-ray probing of NGC 1275 nuclear region with Hitomi, Swift, and Suzaku

2018 ◽  
Vol 14 (S342) ◽  
pp. 118-121
Author(s):  
Yasushi Fukazawa
Keyword(s):  
Gamma Ray ◽  
Seyfert Galaxies ◽  
Continuum Emission ◽  
Line Center ◽  
Nuclear Region ◽  
X Ray ◽  
Line Region ◽  
Flux Increase ◽  
Ngc 1275 ◽  
The Continuum

AbstractNGC 1275 has been known as a ppint-like X-ray source with a continuum and a Fe-K line. Unlike radio and GeV/TeV gamma-ray emissions, origin of X-ray emission is not yet understood; is it a jet emission like blazars or an accretion corona emission like Seyfert galaxies. X-ray emission is important to determine the SED of jet emission to constrain jet parameters and also understand the relation between accretion and jet. Here we report a recent X-ray probing of NGC 1275 nuclear region with Hitomi/SXS, Swift/XRT, and Suzaku/XIS. Hitomi/SXS gave the first opportunity to measure a Fe-K line of AGNs with several eV resolution. The line center is consistent with the neutral iron emission, and the width is constrained to be 500-1600 km/s (FWHM). This ruled out the origin of broad line region and inner accretion disk. A low-covering-fraction molecular torus or a rotating molecular disk around pc scales, illuminated by accretion corona emission, is suggested as a possible origin. For the continuum emission, Suzaku/XIS monitor observations revealed that the X-ray flux has gradually increased as the GeV gamma-ray flux. Swift/XRT showed a several-days flux increase, associated with the GeV gamma-ray flare. These results on the continuum emission suggests a contribution of jet emission to the X-ray emission. Based on the combined results of Fe-K line and continuum, we discuss some scenarios for X-ray emitting region.

The Photometric Properties of the Ap Stars

1976 ◽  
Vol 32 ◽  
pp. 365-377 ◽  
Author(s):  
B. Hauck
Keyword(s):  
Physical Properties ◽  
Ap Stars

The Ap stars are numerous - the photometric systems tool It would be very tedious to review in detail all that which is in the literature concerning the photometry of the Ap stars. In my opinion it is necessary to examine the problem of the photometric properties of the Ap stars by considering first of all the possibility of deriving some physical properties for the Ap stars, or of detecting new ones. My talk today is prepared in this spirit. The classification by means of photoelectric photometric systems is at the present time very well established for many systems, such as UBV, uvbyβ, Vilnius, Geneva and DDO systems. Details and methods of classification can be found in Golay (1974) or in the proceedings of the Albany Colloquium edited by Philip and Hayes (1975).

The Infection of Cells by Bullet-Shaped Viruses

1969 ◽  
Vol 27 ◽  
pp. 372-373
Author(s):  
Frederick A. Murphy ◽  
Alyne K. Harrison ◽  
Sylvia G. Whitfield
Keyword(s):  
Electron Microscopy ◽  
Physical Properties ◽  
Host Cell ◽  
Thin Section ◽  
Cultured Cells ◽  
Cell Infection ◽  
Thin Section Electron Microscopy ◽  
Section Electron ◽  
Section Electron Microscopy

The bullet-shaped viruses are currently classified together on the basis of similarities in virion morphology and physical properties. Biologically and ecologically the member viruses are extremely diverse. In searching for further bases for making comparisons of these agents, the nature of host cell infection, both in vivo and in cultured cells, has been explored by thin-section electron microscopy.

Sign in / Sign up

Export Citation Format

Share Document