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We build a simple physical model to study the high-redshift active galactic Nucleus (AGN) evolution within the co-evolution framework of central black holes (BHs) and their host galaxies. The correlation between the circular velocity of a…

Astrophysics of Galaxies · Physics 2016-09-21 Jirong Mao , Minsun Kim

Although the optical colour-magnitude diagram of galaxies allows one to select red sequence objects, neither can it be used for galaxy classification without additional observational data such as spectra or high-resolution images, nor to…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Igor Chilingarian , Ivan Zolotukhin

Astronomical adaptive optics (AO) has come into its own. Major O/IR telescopes are achieving diffraction-limited imaging; major facilities are being built with AO as an integral part. To the layperson, it may seem that AO has developed…

Instrumentation and Methods for Astrophysics · Physics 2012-04-02 Katie M. Morzinski , Jared R. Males

We present the clustering properties and halo occupation distribution (HOD) modelling of very low redshift, hard X-ray-detected active galactic nuclei (AGN) using cross-correlation function measurements with Two-Micron All Sky Survey…

Astrophysics of Galaxies · Physics 2017-12-01 Mirko Krumpe , Takamitsu Miyaji , Alison L. Coil , Hector Aceves

Dwarf galaxies are ideal laboratories to study the relationship between the environment and AGN activity. However, the type of environments in which dwarf galaxies hosting AGN reside is still unclear and limited to low-redshift studies (z <…

Astrophysics of Galaxies · Physics 2022-11-09 M. Siudek , M. Mezcua , J. Krywult

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

The use of laser guide stars in astronomical adaptive optics results in elongated Shack-Hartmann wavefront sensor image patterns. Image correlation techniques can be used to determine local wavefront slope by correlating each sub-aperture…

Instrumentation and Methods for Astrophysics · Physics 2014-03-05 Alastair Basden

In the recent Astro2020 Decadal Report, ''Pathways to Discovery in Astronomy and Astrophysics for the 2020s'' Adaptive Optics (AO) was identified as a crucial technology for a variety of reasons. These included an emphasis on high-contrast…

Instrumentation and Methods for Astrophysics · Physics 2024-02-13 Julian Christou , Mark Chun , Richard Dekany , Philip Hinz , Jessica Lu , Jared Males , Peter Wizinowich

Luminous AGNs are usually selected by their non-stellar colours or their X-ray emission. Colour selection cannot be used to select low-luminosity AGNs, since their emission is dominated by the host galaxy. Objects with low X-ray to optical…

Astrophysics of Galaxies · Physics 2009-11-13 K. Boutsia , B. Leibundgut , D. Trevese , F. Vagnetti

We describe an Artificial Neural Network (ANN) approach to classification of galaxy images and spectra. ANNs can replicate the classification of galaxy images by a human expert to the same degree of agreement as that between two human…

Astrophysics · Physics 2007-05-23 Ofer Lahav

Active Galactic Nuclei (AGN) sources feature supermassive black holes that launch relativistic plasma jets. They are key $\gamma$-ray sources providing a unique laboratory for studying extreme particle acceleration and plasma physics.…

High Energy Astrophysical Phenomena · Physics 2026-02-03 Luana Passos-Reis , Elisabete M. de Gouveia Dal Pino , Tarek Hassan , Santiago Pita , Alberto Domínguez

Machine-learning (ML) algorithms will play a crucial role in studying the large datasets delivered by new facilities over the next decade and beyond. Here, we investigate the capabilities and limits of such methods in finding galaxies with…

Instrumentation and Methods for Astrophysics · Physics 2019-08-22 Andreas L. Faisst , Abhishek Prakash , Peter L. Capak , Bomee Lee

We propose a large quasar demographic optical multi-object spectroscopic (MOS) survey targeting over 50 million AGN candidates up to the highest redshifts possible in the optical (z~6.5), with repeat visits, using a variety of selection…

We describe the results from a new instrument which combines Lucky Imaging and Adaptive Optics to give the first routine direct diffraction-limited imaging in the visible on a 5m telescope. With fast image selection behind the Palomar AO…

Capitalizing on the all-sky coverage of {\it WISE}, and the 35\% and 50\% sky coverage from SDSS and Pan-STARRS, respectively, we explore the efficacy of $m_{R}$ (optical) - $m_{3.4 \mu m}$ (mid-infrared), hereafter $R-W1$, as a color…

The recent discovery of gravitational radiation from merging black holes poses a challenge of how to organize the electromagnetic follow-up of gravitational-wave events as well as observed bursts of neutrinos. We propose a technique to…

High Energy Astrophysical Phenomena · Physics 2017-02-01 Elisa Antolini , Ilaria Caiazzo , Romeel Davé , Jeremy S. Heyl

Adaptive optics (AO) systems and image reconstruction algorithms are indispensable tools when it comes to high-precision astrometry. In this paper, we analyze the potential of combining both techniques, i.e. by applying image reconstruction…

Instrumentation and Methods for Astrophysics · Physics 2019-03-13 Felix Bosco , Jörg-Uwe Pott , Rainer Schödel

Performances of an adaptive optics (AO) system are directly linked with the quality of its alignment. During the instrument calibration, having open loop fast tools with a large capture range are necessary to quickly assess the system…

We describe several projects addressing the growth of galaxies and massive black holes, for which adaptive optics is mandatory to reach high spatial resolution but is also a challenge due to the lack of guide stars and long integrations. In…

Instrumentation and Methods for Astrophysics · Physics 2015-05-19 Richard Davies , Hauke Engel , Erin Hicks , Natascha Foerster Schreiber , Reinhard Genzel , Linda Tacconi , Frank Eisenhauer , Sebastian Rabien
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