Results 31 to 40 of about 1,130 (187)
Review on Active-Galactic Nuclei at hard X-ray energies [PDF]
Proceedings of An INTEGRAL view of the high-energy sky (the first 10 years) - 9th INTEGRAL Workshop and celebration of the 10th anniversary of the launch — PoS(INTEGRAL 2012), 2013 Hard X-ray surveys are an important tool for the study of active galactic nuclei (AGN): they provide almost an unbiased view of absorption in the extragalactic population, allow the study of spectral features such as reflection and high energy cut-off which would otherwise be unexplored and favour the discovery of some blazars at high redshift.
Bassani, Loredana +8 more
openaire +2 more sources
X-ray absorption in Active Galactic Nuclei
, 2007 10 pages, 4 figures, Conference proceedings to appear in "The Central Engine of Active Galactic Nuclei", ed. L. C. Ho and J.-M. Wang (San Francisco: ASP)
Maiolino, R., Risaliti, G.
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Radiation pressure acceleration by X-rays in active galactic nuclei [PDF]
Monthly Notices of the Royal Astronomical Society, 2001 We present calculations of the dynamics of highly ionized gas clouds that are confined by external pressure, and are ionized by AGN continuum. We focus on the gas that is seen in absorption in the X-ray spectrum of many AGN and show that such gas can reach hydrostatic equilibrium under various conditions. The principal conclusion is that the clouds can
Chelouche, Doron, Netzer, Hagai
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The Astrophysical JournalA core sample of 59 unobscured type 1 active galactic nuclei (AGNs) with simultaneous XMM-Newton X-ray and UV observations is compiled from the archives to probe the nature of soft X-ray excess (SE).
Shi-Jiang Chen +7 more
doaj +1 more source
The Astrophysical JournalWe conduct precise measurements of active galactic nucleus (AGN) clustering at z ∼ 1 and z ∼ 2 by measuring the two-point cross-correlation function (CCF) between galaxies and X-ray-selected AGNs, and the two-point autocorrelation function (ACF) of ...
Hiroyuki Ikeda +8 more
doaj +1 more source
Journal of Field Robotics, EarlyView.ABSTRACT As a crucial puzzle piece of deep space exploration, exploring small bodies can provide significant scientific insights and valuable mineral resources. Unlike missions to the Moon and Mars, small‐body missions pose distinct technical challenges, including communication delays, weak gravity, and uncertain environments. This paper reviews a full
Xin Zhang +3 more
wiley +1 more source
Active Galactic Nuclei with High-Resolution X-Ray Spectroscopy
, 2023 Invited review chapter for the book High-Resolution X-Ray Spectroscopy: Instrumentation, Data Analysis, and Science (Eds. C. Bambi and J. Jiang, Springer Singapore, expected in 2023).
Gallo, Luigi C. +2 more
openaire +2 more sources
The NH Distribution of Hard X-Ray Selected Active Galactic Nuclei in the NEP Field
The Astrophysical JournalX-ray surveys are one of the most unbiased methods for detecting Compton-thick (CT; N _H ≥ 10 ^24 cm ^−2 ) active galactic nuclei (AGN), which are thought to comprise up to 60% of AGN within z ≲ 1.0.
Samantha Creech +11 more
doaj +1 more source
A Low‐Power Radioisotope XRF Spectrometer for Detection of Light Elements on Planetary Missions
X-Ray Spectrometry, EarlyView.ABSTRACT Current X‐ray spectrometers for in situ geochemical analysis on planetary missions typically rely either on X‐ray tubes, which demand electrical power and add mass and thermal complexity, or on alpha particle X‐ray spectrometers (APXS) that use rare 244Cm$$ {}^{244}\mathrm{Cm} $$ sources, and come with severe concerns on radiation safety and ...
Leandro Silveri +14 more
wiley +1 more source
The Astrophysical JournalX-ray variability provides a powerful probe of the innermost regions of active galactic nuclei (AGNs), offering valuable insights into the accretion process and the structure of the corona.
Ruisong Xia +11 more
doaj +1 more source