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We present results from a joint Xmm-Newton/NuSTAR monitoring of the Seyfert 1 NGC 4593, consisting of 5x20 ks simultaneous observations spaced by two days, performed in January 2015. The source is variable, both in flux and spectral shape,…

High Energy Astrophysical Phenomena · Physics 2016-08-17 F. Ursini , P. -O. Petrucci , G. Matt , S. Bianchi , M. Cappi , B. De Marco , A. De Rosa , J. Malzac , A. Marinucci , G. Ponti , A. Tortosa

We discuss preliminary results from a joint XMM-Newton and NuSTAR monitoring program on the active galactic nucleus NGC 4593, consisting of 5x20 ks observations, spaced by two days, performed in January 2015. The source is found to be…

High Energy Astrophysical Phenomena · Physics 2016-05-25 F. Ursini , P. -O. Petrucci , G. Matt , S. Bianchi , M. Cappi , B. De Marco , A. De Rosa , J. Malzac , G. Ponti

We discuss the results of a campaign to monitor spectral variations in the low-luminosity Seyfert~1 galaxy NGC~4593, at X-rays, ultraviolet, optical and near IR frequencies. The observations and data analysis have been described in a…

Astrophysics · Physics 2015-06-24 M. Santos-Lleo , J. Clavel , P. Barr , I. S. Glass , D. Pelat , B. M. Peterson , G. Reichert

In this paper, we make a multi-epoch analysis of NGC 1052, one of the prototypical LLAGN, using XMM-Newton, Suzaku and NuSTAR observations, taken from 2001 to 2017. This is the first time that results from NuSTAR observations are reported…

We report on the short and long term X-ray properties of the bright nearby Seyfert 2 galaxy NGC 2992, which was extensively observed with Swift, XMM-Newton and NuSTAR. Swift targeted the source more than 100 times between 2019 and 2021 in…

High Energy Astrophysical Phenomena · Physics 2022-05-25 R. Middei , A. Marinucci , V. Braito , S. Bianchi , B. De Marco , A. Luminari , G. Matt , E. Nardini , M. Perri , J. N. Reeves , F. Vagnetti

Changing-look active galactic nuclei (CLAGNs) are known to change their spectral type between 1 and 2 (changing-state) or change their absorption between Compton-thick and Compton-thin (changing-obscuration) on timescales of years or less.…

High Energy Astrophysical Phenomena · Physics 2025-01-17 Bing Lyu , Zhen Yan , Xue-bing Wu , Qingwen Wu , Wenfei Yu , Hao Liu

We present the results of a 17 ks Chandra ACIS-S observation of the nearby dwarf spiral galaxy NGC 4395. Chandra affords the first high-quality, broadband X-ray detection of the active nucleus of this object that is uncontaminated by nearby…

Low luminosity active galactic nuclei are more abundant and closer to us than the luminous ones but harder to explore as they are faint. We have selected the four sources NGC 315, NGC 4261, NGC 1275, and NGC 4486, which have been detected…

High Energy Astrophysical Phenomena · Physics 2021-10-13 Gunjan Tomar , Nayantara Gupta , Raj Prince

Low-luminosity active galactic nuclei (LLAGN; $L_{\rm bol} < 10^{42}$~erg~s$^{-1}$) may comprise a significant fraction of the local AGN population, yet their weak emission makes them difficult to detect. In this paper, we analyse 38 LLAGN…

Astrophysics of Galaxies · Physics 2026-05-19 M. N. Rosli , A. Annuar

We present the first robust evidence of an anti-correlation between the X-ray photon index, \Gamma, and the X-ray luminosity in a single low luminosity active galactic nuclei (LLAGN), NGC 7213. Up to now, such anti-correlation trends have…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 D. Emmanoulopoulos , I. E. Papadakis , I. M. McHardy , P. Arevalo , D. E. Calvelo , P. Uttley

Context. Our consortium performed an extensive multi-wavelength campaign of the nearby Seyfert 1 galaxy NGC 5548 in 2013-14. The source appeared unusually heavily absorbed in the soft X-rays, and signatures of outflowing absorption were…

We report hints for the correlation between the X-ray and gamma-ray emission in the nearby galaxy NGC 4945, which harbors both an active galactic nucleus and a nuclear starburst region. We have divided the Fermi/LAT observations of NGC 4945…

High Energy Astrophysical Phenomena · Physics 2017-11-15 Rafal Wojaczynski , Andrzej Niedzwiecki

We have observed four low-luminosity active galactic nuclei classified as Type 1 LINERs with the X-ray Telescope (XRT) and the UltraViolet-Optical Telescope (UVOT) onboard Swift, in an attempt to clarify the main powering mechanism of this…

High Energy Astrophysical Phenomena · Physics 2015-05-14 Elena Pian , Patrizia Romano , Dan Maoz , Antonino Cucchiara , Claudio Pagani , Valentina La Parola

Obscured active galactic nuclei (AGNs) are thought to be very common in the Universe. Observations and surveys have shown that the number of sources increases for near galaxies and at the low-luminosity regime (the so-called LLAGNs).…

We use ROSAT HRI spatial data and ASCA spectral measurements for a sample of seven nearby, early type spiral galaxies, to address the question of whether a low-luminosity Active Galactic Nucleus (LLAGN) is present in galaxies that have a…

Astrophysics · Physics 2016-08-30 T. P. Roberts , N. J. Schurch , R. S. Warwick

We report the analysis of simultaneous XMM-Newton+NuSTAR observations of two low-luminosity Active Galactic Nuclei (LLAGN), NGC 3998 and NGC 4579. We do not detect any significant variability in either source over the ~3 day length of the…

Astrophysics of Galaxies · Physics 2019-01-16 George Younes , Andrew Ptak , Luis C. Ho , Fu-Guo Xie , Yuichi Terasima , Feng Yuan , Daniela Huppenkothen , Mihoko Yukita

We present the analysis of four NuSTAR observations of the luminous infrared galaxy merger NGC 6240, hosting a close pair of highly obscured active galactic nuclei (AGN). Over a period of about two years, the source exhibits hard X-ray…

High Energy Astrophysical Phenomena · Physics 2017-08-23 Emanuele Nardini

We report the detection of a heavily obscured Active Galactic Nucleus (AGN) in the luminous infrared galaxy (LIRG) NGC 6286, identified in a 17.5 ks NuSTAR observation. The source is in an early merging stage, and was targeted as part of…

Recent studies have suggested that the short-timescale ($\lesssim7$ days) variability of the broad ($\sim$10,000 km s$^{-1}$) double-peaked H$\alpha$ profile of the LINER nucleus of NGC1097 could be driven by a variable X-ray emission from…

We report preliminary results from an arcsecond-resolution X-ray survey of nearby galaxies using ACIS on board Chandra. The total sample consists of 41 low-luminosity AGNs, including Seyferts, LINERs, and LINER/H II transition objects. In…

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