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Related papers: Chandra Grating Observations of AGN

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We present a study of the core of the Fe Ka emission line at ~6.4 keV in a sample of type II Seyfert galaxies observed by the Chandra High Energy Grating (HEG). The sample consists of 29 observations of 10 unique sources. We present…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Xinwen Shu , Tahir Yaqoob , Junxian Wang

We report on the results of 18 observations of the core, or peak, of the Fe K emission line at $\sim 6.4$ keV in 15 Seyfert I galaxies using the {\it Chandra} High Energy Grating (HEG). These data afford the highest precision measurements…

Astrophysics · Physics 2009-11-10 Tahir Yaqoob , Urmila Padmanabhan

We present measurements of the Fe-K line for nine Seyfert I galaxies using Chandra High Energy Transmission Grating Spectrometer (HETGS) data. The centroid energies are narrowly dispersed (6.403 +/- 0.062 keV) and indicate an origin of the…

Astrophysics · Physics 2007-05-23 U. Padmanabhan , T. Yaqoob

We present a study of the narrow Fe K$\alpha$ line in seven bright, nearby AGN that have been observed extensively with the Chandra High Energy Transmission Grating (HETG). The HETG data reveal a wider Fe K$\alpha$ line in the first order…

High Energy Astrophysical Phenomena · Physics 2022-09-07 Megan Masterson , Christopher S. Reynolds

We present new results from a Chandra HETG observation of NGC 5548 and give a comparison of absorption and emission features found in other Seyfert 1 galaxies using Chandra grating observations. Deep soft X-ray edges are seen in Mkn 509 and…

Astrophysics · Physics 2007-05-23 T. Yaqoob , I. M. George , T. J. Turner

Chandra and XMM observations are showing that the Fe-K emission lines in type 1 AGN are composite, in general consisting of a narrow and a broad component. We review the latest Chandra HETG results and compare the line profiles with those…

Astrophysics · Physics 2007-05-23 T. Yaqoob , U. Padmanabhan , T. Dotani , I. M. George , T. J. Turner , K. Nandra

In active galactic nuclei (AGN), fluorescent Fe K$\alpha$ (iron) line emission is generally interpreted as originating from obscuring material around a supermassive black hole (SMBH) on the scale of a few parsecs (pc). However, recent…

Astrophysics of Galaxies · Physics 2021-06-30 Wei Yan , Ryan C. Hickox , Chien-Ting J. Chen , Claudio Ricci , Alberto Masini , Franz E. Bauer , David M. Alexander

Recent observations of nearby Compton thick (CT) active galactic nuclei (AGNs) with Chandra have resolved hard (>3 keV) X-ray emission extending out from the central supermassive black hole to kiloparsec scales, challenging the long-held…

Astrophysics of Galaxies · Physics 2020-03-25 Mackenzie L. Jones , G. Fabbiano , Martin Elvis , A. Paggi , M. Karovska , W. P. Maksym , A. Siemiginowska , J. Raymond

The 6.4 keV Fe Ka emission line is a ubiquitous feature in X-ray spectra of AGN, and its properties track the interaction between the variable primary X-ray continuum and the surrounding structure from which it arises. We clarify the nature…

We extend the study of the core of the Fe K$\alpha$ emission line at \sim 6.4 keV in Seyfert galaxies reported in Yaqoob & Padmanabhan (2004) using a larger sample observed by the Chandra High Energy Grating (HEG). Whilst heavily obscured…

High Energy Astrophysical Phenomena · Physics 2015-05-18 X. W. Shu , T. Yaqoob , J. X. Wang

We present the results of the spatial and spectral analysis of the deep (~200 ksec) Chandra HETG observation of the changing look AGN NGC7582. During this observation NGC7582 was in a highly obscured state. Therefore, we considered also a…

High Energy Astrophysical Phenomena · Physics 2017-04-19 Valentina Braito , James Reeves , Stefano Bianchi , Emanuele Nardini , Enrico Piconcelli

(ABRIDGED) AIMS: We searched for X-ray signatures of AGN in a sample of star-forming, relatively early-type, nearby spiral galaxies. Such galaxies are likely to host nuclear super-massive black holes. METHODS: For 9 sources from the Ho et…

Astrophysics · Physics 2008-11-26 P. Tzanavaris , I. Georgantopoulos

We present some early results on AGN from the Chandra X-ray Observatory, highlighting high resolution spectroscopy using the High Energy Transmission Grating Spectrometer (HETGS). The quasar PKS 0637-752 was found to have a very bright…

Astrophysics · Physics 2009-10-31 H. L. Marshall

We report the detection of complex Fe K line emission from a Chandra High Energy Transmission Grating Spectrometer observation of the Seyfert 1 galaxy IC 4329A. The line emission is double-peaked, one peak centered at ~6.3 keV, and the…

Astrophysics · Physics 2009-11-10 B. McKernan , T. Yaqoob

X-ray fluorescent lines are unique features of the reflection spectrum of the cold torus when irradiated by the central AGN. Their intrinsic line widths can be used to probe the line-emitting region. The line widths of the Fe \Ka line…

High Energy Astrophysical Phenomena · Physics 2016-09-28 Jiren Liu

High-resolution X-ray spectra of $\pi\,$Aqr, a $\gamma\,$Cas-type star, obtained with the Chandra/HETG grating spectrometer, revealed emission lines of H-like ions of Mg, Si, S, and Fe, a strong, hard continuum, and a lack of He-like ions,…

We report a clumpy elongated feature found with deep Chandra ACIS high-resolution imaging of the Fe K{\alpha} line emission in the nuclear region of the Compton Thick Active Galactic Nucleus (CT AGN) galaxy NGC 5643. This feature extends…

High Energy Astrophysical Phenomena · Physics 2018-12-26 G. Fabbiano , A. Paggi , A. Siemiginowska , M. Elvis

We report the detection of a narrow Fe-K emission line in the Seyfert 1 galaxy NGC 5548 with the Chandra High-Energy Transmission Gratings. In the galaxy frame we measure a center energy of 6.40 \pm 0.03 keV, a FWHM of 4515 (+3525,-2645)…

Astrophysics · Physics 2009-10-31 T. Yaqoob , I. M. George , K. Nandra , T. J. Turner , P. J. Serlemitsos , R. F. Mushotzky

Chandra X-ray Observatory grating spectra of the supergiant X-ray Binary 4U 1700-37 reveal emission lines from hydrogen and helium-like S, Si, Mg, and Ne in the 4-13 A range. The spectrum also shows fluorescent lines from S, Si, and a…

Astrophysics · Physics 2009-11-07 B. Boroson , S. Vrtilek , T. Kallman , M. Corcoran

We present an analysis of the narrow Fe K-alpha line in Chandra/HETGS observations of the Seyfert AGN, NGC 4151. The sensitivity and resolution afforded by the gratings reveal asymmetry in this line. Models including weak Doppler boosting,…

High Energy Astrophysical Phenomena · Physics 2018-10-10 J. M. Miller , E. Cackett , A. Zoghbi , D. Barret , E. Behar , L. W. Brenneman , A. C. Fabian , J. S. Kaastra , A. Lohfink , . R. Mushotzky , K. Nandra , J. Raymond
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