X-ray properties of bright far-infrared galaxies

1992 ◽  
Vol 388 ◽  
pp. 82 ◽  
Author(s):  
L. P. David ◽  
C. Jones ◽  
W. Forman
Keyword(s):  
Far Infrared ◽  
Infrared Galaxies ◽  
X Ray

scholarly journals AGN Absorption Linked to Host Galaxies

2013 ◽  
Vol 9 (S304) ◽  
pp. 319-322
Author(s):  
Stéphanie Juneau
Keyword(s):  
Star Formation Rate ◽  
Formation Rate ◽  
Far Infrared ◽  
Host Galaxies ◽  
Infrared Galaxies ◽  
Nuclear Activity ◽  
X Ray ◽  
Star Forming ◽  
Diagnostic Diagram ◽  
X Ray Absorption

AbstractMultiwavelength identification of AGN is crucial not only to obtain a more complete census, but also to learn about the physical state of the nuclear activity (obscuration, efficiency, etc.). A panchromatic strategy plays an especially important role when the host galaxies are star-forming. Selecting far-Infrared galaxies at 0.3<z<1, and using AGN tracers in the X-ray, optical spectra, mid-infrared, and radio regimes, we found a twice higher AGN fraction than previous studies, thanks to the combined AGN identification methods and in particular the recent Mass-Excitation (MEx) diagnostic diagram. We furthermore find an intriguing relation between AGN X-ray absorption and the specific star formation rate (sSFR) of the host galaxies, indicating a physical link between X-ray absorption and either the gas fraction or the gas geometry in the hosts. These findings have implications for our current understanding of both the AGN unification model and the nature of the black hole-galaxy connection.

Properties of OH Megamaser Galaxies

1998 ◽  
Vol 11 (2) ◽  
pp. 949-951
Author(s):  
Rafik Kandalyan
Keyword(s):  
Luminosity Function ◽  
Far Infrared ◽  
Main Line ◽  
Spectral Energy ◽  
Amplification Coefficient ◽  
Infrared Galaxies ◽  
Expected Number ◽  
Energy Distributions ◽  
X Ray ◽  
Luminous Infrared Galaxies

AbstractAn analysis of a sample of OH megamaser galaxies is presented. It is shown that the dependence of OH luminosity on FIR (far infrared) luminosity is not quadratic, as previously assumed, but closer to linear. Using a luminosity function of the luminous infrared galaxies, as well as linear relationship between OH and FIR luminosities the expected number of OH megamaser galaxies has been estimated. Spectral energy distributions (SED) of 16 megamaser galaxies have been constructed using multiwavelength (from radio to X-ray) data. The SED of megamasers look closely similar from radio to X-ray. It is shown that the maser amplification coefficient depends both on the OH main line to 60 micron ratio and the main line to 2.2 micron ratio. The OH main lines ratio (f1667/f1665) decreases, while the flux density at 10 micron is increasing.

Tracing young SMBHs in the dusty distant universe – a Chandra view of DOGs

2020 ◽  
Vol 15 (S359) ◽  
pp. 17-21
Author(s):  
Karín Menéndez-Delmestre ◽  
Laurie Riguccini ◽  
Ezequiel Treister
Keyword(s):  
Star Formation ◽  
Main Sequence ◽  
Far Infrared ◽  
Host Galaxy ◽  
X Ray ◽  
Star Forming ◽  
Near Ir ◽  
X Ray Imaging ◽  
Combined Use ◽  
Dusty Galaxies

AbstractThe coexistence of star formation and AGN activity has geared much attention to dusty galaxies at high redshifts, in the interest of understanding the origin of the Magorrian relation observed locally, where the mass of the stellar bulk in a galaxy appears to be tied to the mass of the underlying supermassive black hole. We exploit the combined use of far-infrared (IR) Herschel data and deep Chandra ˜160 ksec depth X-ray imaging of the COSMOS field to probe for AGN signatures in a large sample of >100 Dust-Obscured Galaxies (DOGs). Only a handful (˜20%) present individual X-ray detections pointing to the presence of significant AGN activity, while X-ray stacking analysis on the X-ray undetected DOGs points to a mix between AGN activity and star formation. Together, they are typically found on the main sequence of star-forming galaxies or below it, suggesting that they are either still undergoing significant build up of the stellar bulk or have started quenching. We find only ˜30% (6) Compton-thick AGN candidates (NH > 1024 cm–2), which is the same frequency found within other soft- and hard-X-ray selected AGN populations. This suggests that the large column densities responsible for the obscuration in Compton-thick AGNs must be nuclear and have little to do with the dust obscuration of the host galaxy. We find that DOGs identified to have an AGN share similar near-IR and mid-to-far-IR colors, independently of whether they are individually detected or not in the X-ray. The main difference between the X-ray detected and the X-ray undetected populations appears to be in their redshift distributions, with the X-ray undetected ones being typically found at larger distances. This strongly underlines the critical need for multiwavelength studies in order to obtain a more complete census of the obscured AGN population out to higher redshifts. For more details, we refer the reader to Riguccini et al. (2019).

Cobalt(II) Mercury Tetrathiocyanate Complexes with Lewis Bases

1973 ◽  
Vol 51 (3) ◽  
pp. 438-447 ◽  
Author(s):  
R. Makhija ◽  
L. Pazdernik ◽  
R. Rivest
Keyword(s):  
Magnetic Susceptibility ◽  
Powder Diffraction ◽  
Elemental Analysis ◽  
Far Infrared ◽  
Crystalline Solid ◽  
Ultraviolet Spectroscopy ◽  
X Ray ◽  
Lewis Bases ◽  
Polydentate Ligands

A new series of octahedral cobalt(II) complexes are formed when CoX2(X = Cl, Br, I, SCN) reacts with Hg(SCN)2 in the presence of Lewis bases. These complexes of stoichiometry CoHg(SCN)4•2L (L = THF, dioxane, pyridine, aniline) are pink to violet solids which slowly decompose to the blue crystalline solid, CoHg(SCN)4, the stable magnetic susceptibility standard. On further reaction of CoHg(SCN)4•2THF with mono-, bi-, and polydentate ligands in dry ethanol, complexes of the following types are obtained: CoHg(SCN)4•2L (L = PΦ3), CoHg(SCN)4•2LL (LL = trien), CoHg(SCN)4•3LL (LL = en, bipy), and CoHg(SCN)4•4LL (LL = phen). The stoichiometry of these were determined by elemental analysis. Possible structures of these are discussed with the help of mid and far infrared, visible, and ultraviolet spectroscopy, magnetic susceptibility, and X-ray powder diffraction. Some new i.r. bands like Co—P, Co—N, and Hg—S are assigned in the low region.

Radiation Production Using Femtosecond Electron Bunches

2005 ◽  
Vol 107 ◽  
pp. 11-14
Author(s):  
C. Thongbai ◽  
V. Jinamoon ◽  
N. Kangrang ◽  
K. Kusoljariyakul ◽  
S. Rimjaem ◽  
...  
Keyword(s):  
Far Infrared ◽  
Bunch Length ◽  
X Rays ◽  
Research Facility ◽  
X Ray ◽  
Electron Bunches ◽  
Rf Gun ◽  
Intense Radiation ◽  
Far Infrared Radiation ◽  
Femtosecond Electron Bunches

Femtosecond electron bunches can be generated from a system consisting of an RF gun with a thermionic cathode, an alpha magnet, and a linear accelerator and can be used to produce femtosecond (fs) electromagnetic radiation pulses. At the Fast Neutron Research Facility (FNRF), Thailand, we are especially interested in production in Far-infrared (FIR) and x-radiation. In the far-infrared, radiation is emitted coherently for wavelengths which are longer than the electron bunch length, yielding intense radiation. Although, the x-rays emitted are incoherent, its femtosecond time scale is crucial for development of a femtosecond x-ray source.

Grating groove metrology and efficiency predictions from the soft x-ray to the far infrared

2002 ◽  
Author(s):  
David A. Content ◽  
Petar Arsenovic ◽  
Ivan G. Kuznetsov ◽  
Theo Hadjimichael
Keyword(s):  
Far Infrared ◽  
X Ray

scholarly journals The Far‐Infrared Spectral Energy Distributions of X‐Ray–selected Active Galaxies

2003 ◽  
Vol 590 (1) ◽  
pp. 128-148 ◽  
Author(s):  
Joanna K. Kuraszkiewicz ◽  
Belinda J. Wilkes ◽  
Eric ◽  
J. Hooper ◽  
Kim K. McLeod ◽  
...  
Keyword(s):  
Far Infrared ◽  
Active Galaxies ◽  
Spectral Energy ◽  
Spectral Energy Distributions ◽  
Energy Distributions ◽  
X Ray ◽  
Infrared Spectral

scholarly journals AHerschel/PACS Far-infrared Line Emission Survey of Local Luminous Infrared Galaxies

2017 ◽  
Vol 846 (1) ◽  
pp. 32 ◽  
Author(s):  
T. Díaz-Santos ◽  
L. Armus ◽  
V. Charmandaris ◽  
N. Lu ◽  
S. Stierwalt ◽  
...  
Keyword(s):  
Line Emission ◽  
Far Infrared ◽  
Infrared Galaxies ◽  
Luminous Infrared Galaxies

scholarly journals Radio Loud Far-Infrared Galaxies

1990 ◽  
Vol 124 ◽  
pp. 309-314 ◽  
Author(s):  
Arjun Dey ◽  
Wil van Breugel ◽  
Joseph C. Shields
Keyword(s):  
Star Formation ◽  
Radio Emission ◽  
Point Source ◽  
Optical Imaging ◽  
Radio Galaxy ◽  
Far Infrared ◽  
Infrared Galaxies ◽  
Galaxy Interactions ◽  
First Results ◽  
Radio Survey

AbstractWe present the first results of a multiwavelength study of IRAS galaxies with excess radio emission. The sample was selected by cross-correlating the IRAS Faint Source Survey (for |b| ≥ 50°) and the Point Source Catalogue (for 10° < |b| < 50°) with the Texas radio survey. Recent optical (imaging and spectroscopic) and radio (VLA) observations are discussed. These observations will be used to investigate possible connections between radio galaxy activity, star formation and galaxy interactions.

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