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Related papers: Predicting the redshift of gamma-ray loud AGNs usi…

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We present an analysis of deep multiwavelength data for z ~ 0.3-3 starburst galaxies selected by their 70 um emission in the Extended-Chandra Deep Field-South and Extended Groth Strip. We identify active galactic nuclei (AGNs) in these…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 D. A. Rafferty , W. N. Brandt , D. M. Alexander , Y. Q. Xue , F. E. Bauer , B. D. Lehmer , B. Luo , C. Papovich

Estimating redshift is a central task in astrophysics, but its measurement is costly and time-consuming. In addition, current image-based methods are often validated on homogeneous datasets. The development and comparison of networks able…

Instrumentation and Methods for Astrophysics · Physics 2026-03-17 Alessandro Meroni , Nicolò Oreste Pinciroli Vago , Piero Fraternali

Dual-Active Galactic Nuclei (AGN) are a natural consequence of the hierarchical structure formation scenario, and can provide an important test of various models for black hole growth. However, due to their rarity and difficulty to find at…

Astrophysics of Galaxies · Physics 2021-09-22 C. S. Mangat , J. P. McKean , R. Brilenkov , P. Hartley , H. R. Stacey , S. Vegetti , D. Wen

We present a new method to interpret the $\gamma$-ray data of our inner Galaxy as measured by the Fermi Large Area Telescope (Fermi LAT). We train and test convolutional neural networks with simulated Fermi-LAT images based on models tuned…

High Energy Astrophysical Phenomena · Physics 2018-05-29 Sascha Caron , Germán A. Gómez-Vargas , Luc Hendriks , Roberto Ruiz de Austri

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

Over the last few years, the existence of mutual feedback effects between accreting supermassive black holes powering AGN and star formation in their host galaxies has become evident. This means that the formation and the evolution of AGN…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 M. Brusa

We use a novel method to predict the contribution of normal star-forming galaxies, merger-induced bursts, and obscured AGN, to IR luminosity functions (LFs) and global SFR densities. We use empirical halo occupation constraints to populate…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-01 Philip F. Hopkins , Joshua D. Younger , Christopher C. Hayward , Desika Narayanan , Lars Hernquist

We present a framework for detecting transient gamma-ray phenomena in a controlled environment by combining end-to-end simulations of the Fermi-LAT sky with self-supervised spatio-temporal deep learning. We generate a ten-year synthetic…

We explore the role of the group environment in the evolution of AGN at the redshift interval 0.7<z<1.4, by combining deep Chandra observations with extensive optical spectroscopy from the All-wavelength Extended Groth strip International…

Astrophysics · Physics 2009-11-13 A. Georgakakis , Brian F. Gerke , K. Nandra , E. S. Laird , A. L. Coil , M. C. Cooper , J. A. Newman

We describe a method to measure the M-sigma relation in the non-local universe using dust-obscured QSOs. We present results from a pilot sample of nine 2MASS red QSOs with redshifts 0.14<z<0.37. We find that there is an offset (0.8 dex, on…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Gabriela Canalizo , Margrethe Wold , Kyle D. Hiner , Mariana Lazarova , Mark Lacy , Kevin Aylor

We explore the connections between the evolving galaxy and AGN populations. We present a simple phenomenological model that links the evolving galaxy mass function and the evolving quasar luminosity function, which makes specific and…

Astrophysics of Galaxies · Physics 2015-10-07 Neven Caplar , Simon J. Lilly , Benny Trakhtenbrot

We present an analysis of anomaly detection for machine learning redshift estimation. Anomaly detection allows the removal of poor training examples, which can adversely influence redshift estimates. Anomalous training examples may be…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-16 Ben Hoyle , Markus Michael Rau , Kerstin Paech , Christopher Bonnett , Stella Seitz , Jochen Weller

When gravitational waves pass near massive astrophysical objects, they can be gravitationally lensed. The lensing can split them into multiple wave-fronts, magnify them, or imprint beating patterns on the waves. Here we focus on the…

High Energy Astrophysical Phenomena · Physics 2021-11-17 A. Renske A. C. Wierda , Ewoud Wempe , Otto A. Hannuksela , Léon V. E. Koopmans , Chris Van Den Broeck

In the era of large sky surveys, photometric redshifts (photo-z) represent crucial information for galaxy evolution and cosmology studies. In this work, we propose a new Machine Learning (ML) tool called Galaxy morphoto-Z with neural…

We present new results on the cosmological evolution of unabsorbed (type-1) active galactic nuclei (AGN) selected in the soft (0.5-2 keV) X-ray band. From a variety of ROSAT, XMM-Newton and Chandra surveys we selected a total of ~1000 AGN…

Astrophysics · Physics 2009-11-11 G. Hasinger , T. Miyaji , M. Schmidt

In this work, we study the AGN radio detection effectiveness in the major deep extragalactic surveys, considering different AGN obscuration levels, redshift, and AGN bolometric luminosities. We particularly focus on comparing their radio…

We present the first measurement of the AGN fraction in high-redshift clusters of galaxies (z~0.6) with spectroscopy of one cluster and archival data for three additional clusters. We identify 8 AGN in all four of these clusters from the…

We present a measure of the hard (2-8 keV) X-ray luminosity function (XLF) of Active Galactic Nuclei up to z~5. At high redshifts, the wide area coverage of the Chandra Multiwavength Project is crucial to detect rare and luminous (Lx >…

Active galactic nuclei (AGN) are supermassive black holes with luminous accretion disks found in some galaxies, and are thought to play an important role in galaxy evolution. However, traditional optical spectroscopy for identifying AGN…

Astrophysics of Galaxies · Physics 2022-12-16 Ziting Guo , John F. Wu , Chelsea E. Sharon

We have incorporated the description of the X-ray properties of Active Galactic Nuclei (AGNs) into a semi-analytic model of galaxy formation, adopting physically motivated scaling laws for accretion triggered by galaxy encounters. Our model…

Astrophysics · Physics 2009-11-10 N. Menci , F. Fiore , G. C. Perola , A. Cavaliere
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