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Related papers: Classifying Seyfert galaxies with deep learning

200 papers

We present spatially resolved BPT mapping of the extended narrow line regions (ENLRs) of seven nearby Seyfert 2 galaxies, using HST narrow band filter imaging. We construct the BPT diagrams using $\leq$ 0.1" resolution emission line images…

Modelling the mass distributions of strong gravitational lenses is often necessary to use them as astrophysical and cosmological probes. With the high number of lens systems ($>10^5$) expected from upcoming surveys, it is timely to explore…

Astrophysics of Galaxies · Physics 2021-02-24 S. Schuldt , S. H. Suyu , T. Meinhardt , L. Leal-Taixé , R. Cañameras , S. Taubenberger , A. Halkola

We have selected an all--sky sample of 893 galaxies from the IRAS FSC--2, defined by a total (ADDSCAN) 12um flux limit of 0.22~Jy. Completeness is verified to 0.30~Jy, below which we have quantified the incompleteness down to 0.22~Jy for…

Astrophysics · Physics 2009-10-22 B. Rush , M. A. Malkan , L. Spinoglio

We present a systematic search for wide-separation (Einstein radius >1.5"), galaxy-scale strong lenses in the 30 000 sq.deg of the Pan-STARRS 3pi survey on the Northern sky. With long time delays of a few days to weeks, such systems are…

Astrophysics of Galaxies · Physics 2021-04-08 R. Canameras , S. Schuldt , S. H. Suyu , S. Taubenberger , T. Meinhardt , L. Leal-Taixe , C. Lemon , K. Rojas , E. Savary

The Chinese Space Station Survey Telescope (CSST) aims to map the universe across an unprecedented dynamic range of stellar densities, spanning from extragalactic voids to the crowded Galactic center (e.g. a few stars and galaxies in the…

Instrumentation and Methods for Astrophysics · Physics 2026-05-19 Jinzhi Lai , Man I Lam , Jianjun Chen , Xin Zhang , Hao Tian , Xiaohan Chen , Jialu Nie , Ming Yang , Chao Liu

The Zone of Avoidance makes it difficult for astronomers to catalogue galaxies at low latitudes to our galactic plane due to high star densities and extinction. However, having a complete sky map of galaxies is important in a number of…

Instrumentation and Methods for Astrophysics · Physics 2019-03-21 David Jones , Anja Schroeder , Geoff Nitschke

Machine learning has the potential to improve the reconstruction of the dark matter profile of galaxies with respect to traditional methods, like rotation curves. We demonstrate on the simulation suite Illustris-TNG that a steerable…

Astrophysics of Galaxies · Physics 2025-10-23 Martín de los Rios , Serafina Di Gioia , Fabio Iocco , Roberto Trotta

Convolutional Neural Networks (CNNs) currently achieve state-of-the-art accuracy in image classification. With a growing number of classes, the accuracy usually drops as the possibilities of confusion increase. Interestingly, the class…

Computer Vision and Pattern Recognition · Computer Science 2017-10-25 Bilal Alsallakh , Amin Jourabloo , Mao Ye , Xiaoming Liu , Liu Ren

Seyfert's Sextet (a.k.a HCG 79) is one of the most compact and isolated galaxy groups in the local Universe. It shows a prominent diffuse light component that accounts for ~50% of the total observed light. This likely indicates that the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 S. Tamburri , G. Trinchieri , A. Wolter , J. Sulentic , A. Durbala , M. Rosado

We present archival Hubble Space Telescope images of the nuclear regions of 43 of the 46 Seyfert galaxies found in the volume-limited, spectroscopically-complete CfA Redshift Survey sample. Using an improved method of image contrast…

Astrophysics · Physics 2009-11-07 Richard W. Pogge , Paul Martini

The new generation of deep photometric surveys requires unprecedentedly precise shape and photometry measurements of billions of galaxies to achieve their main science goals. At such depths, one major limiting factor is the blending of…

We have compared the X-ray--to--optical flux ratios (F_x/F_opt) of absorbed active galactic nuclei (AGNs) in the Chandra Deep Field North (CDF-N) with those of nearby, optically classified Seyfert 2 galaxies. The comparison provides an…

Astrophysics · Physics 2009-06-23 Carolin N. Cardamone , Edward C. Moran , Laura E. Kay

We present a new catalog of narrow-line Seyfert 1 (NLSy1) galaxies from the Sloan Digital Sky Survey Data Release 12 (SDSS DR12). This was obtained by a systematic analysis through modeling of the continuum and emission lines of the spectra…

Astrophysics of Galaxies · Physics 2017-04-26 Suvendu Rakshit , C. S. Stalin , Hum Chand , Xue-Guang Zhang

We present the results of broad-band B and I imaging observations for a sample of 88 Seyfert galaxies (29 Seyfert 1's and 59 Seyfert 2's), selected from a mostly isotropic property, the flux at 60$\mu$m. We also present the B and I imaging…

Astrophysics · Physics 2009-10-31 H. R. Schmitt , A. L. Kinney

Based on a new spectroscopic sample observed using the WHT, we examine the kinematic properties of the various emission line regions in narrow line Seyfert 1 galaxies (NLS1s) by modelling their profiles using multiple component fits. We…

Astrophysics · Physics 2009-11-13 James R. Mullaney , Martin J. Ward

Thanks to the execution of extensive spectroscopic surveys that have covered large fractions of the sky down to magnitudes as faint as $i \approx 19$, it has been possible to identify several narrow-line Seyfert 1 galaxies (NLS1s) and to…

Astrophysics of Galaxies · Physics 2018-09-10 G. La Mura , D. Bastieri , M. Berton , S. Chen , S. Ciroi , E. Congiu , V. Cracco , J. -H. Fan , P. Rafanelli

NGC 5033 is an intriguing Seyfert galaxy because its sub-classification may change with time, and because optical and sub-mm observations find that the massive black hole does not sit at the dynamical center of the galaxy, pointing to a…

High Energy Astrophysical Phenomena · Physics 2022-08-17 S. B. Yun , J. M. Miller , D. Barret , D. Stern , W. N. Brandt , L. Brenneman , P. Draghis , A. C. Fabian , J. Raymond , A. Zoghbi

Modulation classification, recognized as the intermediate step between signal detection and demodulation, is widely deployed in several modern wireless communication systems. Although many approaches have been studied in the last decades…

Signal Processing · Electrical Eng. & Systems 2020-09-07 Van-Sang Doan , Thien Huynh-The , Cam-Hao Hua , Quoc-Viet Pham , Dong-Seong Kim

A radio study of a carefully selected sample of 20 Seyfert galaxies that are matched in orientation-independent parameters, which are measures of intrinsic active galactic nuclei (AGN) power and host galaxy properties is presented to test…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Dharam V. Lal , Prajval Shastri , Denise Gabuzda

The hidden broad-line regions (BLRs) in Seyfert 2 galaxies, which display broad emission lines (BELs) in their polarized spectra, are a key piece of evidence in support of the unified model for active galactic nuclei (AGNs). However, the…

Astrophysics of Galaxies · Physics 2017-05-03 Pu Du , Jian-Min Wang , Zhi-Xiang Zhang