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Related papers: The 3.4 micron absorption feature towards three ob…

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We present results of near-infrared photometry (J, H, K_S) for a sample of active galactic nuclei (AGNs) obtained from hard X-ray surveys with ASCA. The sample covers the AGNs at z=0.1-1 with L(2-10keV)=10^42-10^46 erg/s with very high…

Astrophysics · Physics 2009-11-10 Chisato Watanabe , Kouji Ohta , Masayuki Akiyama , Yoshihiro Ueda

We have observed the continuum emission of the interacting galaxy NGC4631 at 0.87 and 1.23mm using the Heinrich-Hertz-Telescope on Mt. Graham and the IRAM 30-m telescope on Pico Veleta. We have obtained fully sampled maps which cover the…

Astrophysics · Physics 2009-11-10 M. Dumke , M. Krause , R. Wielebinski

Using starlight polarization, we present the properties of foreground dust towards cluster NGC 7380 embedded in H{\sc ii} region Sh 2-142. Observations of starlight polarization are carried out in four filters using an imaging polarimeter…

Astrophysics of Galaxies · Physics 2024-04-01 Sadhana Singh , Jeewan C. Pandey , Thiem Hoang , Neelam Panwar , Biman J. Medhi , Vishal Joshi , Shashikiran Ganesh

We presented the multiwavelength analysis of a heavily obscured active galactic nucleus (AGN) in NGC 449. We first constructed a broadband X-ray spectrum using the latest NuSTAR and XMM-Newton data. Its column density ($\simeq 10^{24}…

Astrophysics of Galaxies · Physics 2023-02-15 Xiaotong Guo , Qiusheng Gu , Jun Xu , Guanwen Fang , Xue Ge , Yongyun Chen , Xiaoling Yu , Nan Ding

We present high-resolution (<0.65") optical broad-band images of the edge-on Sb galaxy NGC 891 obtained with the WIYN 3.5-m telescope. These BVR images reveal a complex network of hundreds of dust absorbing structures far from the mid-plane…

Astrophysics · Physics 2009-05-29 J. Christopher Howk , Blair D. Savage

We present a detailed analysis of the most luminous and obscured Active Galactic Nuclei (AGNs) detected in the ultra-hard X-ray band (14-195 keV) by Swift/BAT. Our sample comprises 21 X-ray luminous (log $L_X/{\rm erg\,s^{-1}}>44.6$, 2-10…

We present X-ray spectral analyses for three Seyfert 2 active galactic nuclei, NGC 424, NGC 1320, and IC 2560, observed by NuSTAR in the 3-79 keV band. The high quality hard X-ray spectra allow detailed modeling of the Compton reflection…

We present preliminary results from the highest available signal-to-noise rest-frame 2-8um spectra of z~2 ULIRGs. Our 10 targets are selected for their deep silicate absorption features based on previous shallower IRS spectra. The goal of…

Astrophysics of Galaxies · Physics 2009-03-25 A. Sajina , L. Yan , H. Spoon , D. Fadda

Compact obscured nuclei (CONs) are mainly found in local U/LIRGs. In the local Universe, these sources are generally selected through the detection of the HCN-vib (3-2) emission line at submillimetre wavelengths. In this work, we present a…

(abridged) This paper is the second part of a work investigating the properties of dusty tori in AGN by means of multi-component SED fitting. It focuses on low luminosity, low redshift (z < 0.25) AGN selected among emission line galaxies as…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Evanthia Hatziminaoglou , Jacopo Fritz , Tom Jarrett

We discuss the spectral analysis of a sample of 63 Active Galactic Nuclei (AGN) detected above a limiting flux of $S(8-24$ keV$)=7\times10^{-14}$ erg/s/cm$^2$ in the multi-tiered NuSTAR Extragalactic Survey program. The sources span a…

The silicate cross section peak near 10um produces emission and absorption features in the spectra of dusty galactic nuclei observed with the Spitzer Space Telescope. Especially in ultraluminous infrared galaxies, the observed absorption…

Astrophysics · Physics 2010-11-11 N. A. Levenson , M. M. Sirocky , L. Hao , H. W. W. Spoon , J. A. Marshall , M. Elitzur , J. R. Houck

We present the analysis of Spitzer-IRS spectra of four early-type galaxies, NGC 1297, NGC 5044, NGC 6868, and NGC 7079, all classified as LINERs in the optical bands. Their IRS spectra present the full series of H2 rotational emission lines…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 O. Vega , A. Bressan , P. Panuzzo , R. Rampazzo , M. Clemens , G. L. Granato , L. Buson , L. Silva , W. W. Zeilinger

We present ALMA Cycle 1 observations of the central kpc region of the luminous type-1 Seyfert galaxy NGC 7469 with unprecedented high resolution (0.5$"$ $\times$ 0.4$"$ = 165 pc $\times$ 132 pc) at submillimeter wavelengths. Utilizing the…

We report the first direct X-ray evidence that an AGN is hidden in the center of IRAS12393+3520. An ASCA observation of this target unveiled a bright (0.5-10 keV luminosity 3.9 x 10^42 erg/s) and variable source, with minimum observed…

Astrophysics · Physics 2007-05-23 M. Guainazzi , M. Dennefeld , L. Piro , T. Boller , P. Rafanelli , M. Yamauchi

We present a new sample of active galactic nuclei (AGNs) identified using the catalog of the AKARI Mid-infrared(MIR) All-Sky Survey. Our MIR search has an advantage in detecting AGNs that are obscured at optical wavelengths due to…

Cosmology and Nongalactic Astrophysics · Physics 2011-03-24 S. Oyabu , D. Ishihara , M. Malkan , H. Matsuhara , T. Wada , T. Nakagawa , Y. Ohyama , Y. Toba , T. Onaka , S. Takita , H. Kataza , I. Yamamura , M. Shirahata

We perform a detailed investigation of moderate-to-high quality X-ray spectra of ten of the most luminous active galactic nuclei (AGNs) known at z>4 (up to z~6.28). This study includes five new XMM observations and five archived X-ray…

Astrophysics · Physics 2008-11-26 O. Shemmer , W. N. Brandt , C. Vignali , D. P. Schneider , X. Fan , G. T. Richards , M. A. Strauss

We present a study of reddening and absorption towards the Narrow Line Regions (NLR) in active galactic nuclei (AGN) selected from the Revised Shapley-Ames, 12mu, and Swift/Burst Alert Telescope samples. For the sources in host galaxies…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 S. B. Kraemer , H. R. Schmitt , D. M. Crenshaw , M. Melendez , T. J. Turner , M. Guainazzi. , R. F. Mushotzky

Context. Compact Obscured Nuclei (CONs) are an extreme phase of galaxy evolution where rapid supermassive black hole growth and$/$or compact star-forming activity is completely obscured by gas and dust. Aims. We investigate the properties…

We present the distributions of geometrical covering factors of active galactic nuclei (AGNs) dusty tori (f2) using an X-ray selected complete sample of 227 AGN drawn from the Bright Ultra-hard XMM-Newton Survey. The AGN have z from 0.05 to…