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Related papers: An Active Galactic Nucleus Recognition Model based…

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We present results of recurrence analysis of 46 active galactic nuclei (AGN) using light curves from the 157-month catalog of the Swift Burst Alert Telescope (BAT) in the 14-150 keV band. We generate recurrence plots and compute recurrence…

High Energy Astrophysical Phenomena · Physics 2022-11-28 R. A. Phillipson , M. S. Vogeley , P. T. Boyd

We present the Active Galactic Nuclei (AGN) classifier as currently implemented within the Fink broker. Features were built upon summary statistics of available photometric points, as well as color estimation enabled by symbolic regression.…

Instrumentation and Methods for Astrophysics · Physics 2022-11-22 Etienne Russeil , Emille E. O. Ishida , Roman Le Montagner , Julien Peloton , Anais Moller

Active Galactic Nuclei (AGNs) are among the most luminous objects in the universe, making them valuable probes for studying galaxy evolution. However, understanding how AGN properties evolve over cosmic time remains a fundamental challenge.…

Astrophysics of Galaxies · Physics 2025-05-06 Shreya Sareen , Swayamtrupta Panda

We present ongoing work on the spectral energy distributions (SEDs) of active galactic nuclei (AGNs), derived from X-ray, ultraviolet, optical, infrared and radio photometry and spectroscopy. Our work is motivated by new wide-field imaging…

Astrophysics of Galaxies · Physics 2020-06-17 M. J. I. Brown , K. J. Duncan , H. Landt , M. Kirk , C. Ricci , N. Kamraj

An important question in extragalactic astronomy concerns the distribution of black hole accretion rates of active galactic nuclei (AGN). Based on observations at X-ray wavelengths, the observed Eddington ratio distribution appears as a…

Astrophysics of Galaxies · Physics 2016-07-20 M. L. Jones , R. C. Hickox , C. S. Black , K. N. Hainline , M. A. DiPompeo , A. D. Goulding

One of the main challenges in modeling massive stars to the onset of core collapse is the computational bottleneck of nucleosynthesis during advanced burning stages. The number of isotopes formed requires solving a large set of…

We present the results from performing spectral energy distribution (SED) fitting on 121 variable active galactic nuclei (AGN) candidates in the Hubble Ultra Deep Field (HUDF) using photometry from both the Hubble Space Telescope (HST) and…

Extragalactic radio continuum surveys play an increasingly more important role in galaxy evolution and cosmology studies. While radio galaxies and radio quasars dominate at the bright end, star-forming galaxies (SFGs) and radio-quiet Active…

Deep field observations are an essential tool to probe the cosmological evolution of galaxies. In this context, X-ray deep fields provide information about some of the most energetic cosmological objects: active galactic nuclei (AGN).…

Astrophysics · Physics 2007-05-23 G. Hasinger , A. Mueller

We explore spectroscopic and photometric methods for identifying high-redshift galaxies containing an Active Galactic Nucleus (AGN) with JWST observations. After demonstrating the limitations of standard optical methods, which appear…

Utilizing Chandra X-ray observations in the All-wavelength Extended Groth Strip International Survey (AEGIS) we identify 241 X-ray selected Active Galactic Nuclei (AGNs, L > 10^{42} ergs/s) and study the properties of their host galaxies in…

We apply and compare various Artificial Neural Network (ANN) and other algorithms for automatic morphological classification of galaxies. The ANNs are presented here mathematically, as non-linear extensions of conventional statistical…

Astrophysics · Physics 2015-06-24 O. Lahav , A. Naim , L. Sodre , M. C. Storrie-Lombardi

We have conducted a high-resolution spectroscopic study using Spitzer of 18 bulgeless (Sd/Sdm) galaxies that show no definitive signatures of nuclear activity in their optical spectra. This is the first systematic mid-IR search for weak or…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 S. Satyapal , T. Boeker , W. Mcalpine , M. Gliozzi , N. P. Abel , T. Heckman

We present a study of the active galactic nucleus (AGN) activity in the local Universe (z < 0.33) and its correlation with the host galaxy properties, derived from a Sloan Digital Sky Survey (SDSS DR8) sample with spectroscopic…

Deep convolutional neural networks (DCNNs) have become the most common solution for automatic image annotation due to their non-parametric nature, good performance, and their accessibility through libraries such as TensorFlow. Among other…

Astrophysics of Galaxies · Physics 2022-01-11 Sanchari Dhar , Lior Shamir

Active Galactic Nuclei (AGN) unification, which implies a large number of obscured AGN, can explain the optical, infrared and X-ray content of deep multiwavelength surveys. Here, we show that the same model also successfully explains the…

Astrophysics · Physics 2007-05-23 Ezequiel Treister , C. M. Urry

Active galactic nuclei (AGN) have been observed in dwarf galaxies, yet the impact of black hole feedback in these low-mass systems remains unclear. To uncover the potential effects of AGN in the low-mass galaxy regime, we study the…

X-ray spectroscopy of active galactic nuclei (AGN) offers the opportunity to directly probe the inner regions of the accretion disk. We present the results of our analysis of average AGN XMM-Newton X-ray spectra in the Chandra Deep Field…

High Energy Astrophysical Phenomena · Physics 2014-08-12 S. Falocco , F. J. Carrera , A. Corral , X. Barcons , A. Comastri , R. Gilli , P. Ranalli , C. Vignali , K. Iwasawa , N. Cappelluti , E. Rovilos , I. Georgantopoulos , M. Brusa , F. Vito

Galaxy mergers play a crucial role in the formation of massive galaxies and the buildup of their bulges. An important aspect of the merging process is the in-spiral of the supermassive black-holes (SMBHs) to the centre of the merger remnant…

Astrophysics of Galaxies · Physics 2017-08-04 M. Das , K. Rubinur , P. Kharb , A. Varghese , K. Navyasree , A. James

Physical processes such as re-ignition, enhancement, and fading of active galactic nuclei (AGN) are not entirely understood because the timeline of these events is expected to last many years. However, it is well known that the differences…