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Related papers: An iterative method to deblend AGN-Host contributi…

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Context. Most popular algorithms in use to remove the effects of a telescope's point spread function (PSF) in radio astronomy are variants of the CLEAN algorithm. Most of these algorithms model the sky brightness using the delta-function…

Instrumentation and Methods for Astrophysics · Physics 2017-12-18 L. Zhang , S. Bhatnagar , U. Rau , M. Zhang

Several different methods are regularly used to infer the properties of the neutral interstellar medium (ISM) using atomic hydrogen (H I) 21cm absorption and emission spectra. In this work, we study various techniques used for inferring ISM…

Astrophysics of Galaxies · Physics 2023-11-27 Soumyadeep Bhattacharjee , Nirupam Roy , Prateek Sharma , Amit Seta , Christoph Federrath

Context. Medium-resolution IFS, such as MUSE at the VLT, are equipped to detect the emission lines of faint accreting companions when associated with dedicated stellar halo subtraction methods. We recently proposed a new approach based on…

Instrumentation and Methods for Astrophysics · Physics 2025-11-26 R. Julo , M. Bonnefoy , F. Chatelain , O. Flasseur , O. J. J. Michel , S. Jorquera , P. Delorme , G. Chauvin

Classification of galactic morphologies is a crucial task in galactic astronomy, and identifying fine structures of galaxies (e.g., spiral arms, bars, and clumps) is an essential ingredient in such a classification task. However, seeing…

Instrumentation and Methods for Astrophysics · Physics 2021-03-30 Fang Kai Gan , Kenji Bekki , Abdolhosein Hashemizadeh

We report a point spread function (PSF) and deconvolution procedure to remove stray light from the Helioseismic and Magnetic Imager (HMI) data. Pre-launch calibration observations, post-launch Venus transit and lunar transit data were used…

Solar and Stellar Astrophysics · Physics 2025-11-18 A. A. Norton , T. L. Duvall, , J. Schou , R. S. Bogart , J. Zhao , C. Rabello-Soares , P. J. Levens , J. T. Hoeksema , C. S. Baldner

We present a model-independent method of quantifying galaxy evolution in high-resolution images, which we apply to the Hubble Deep Field (HDF). Our procedure is to k-correct all pixels belonging to the images of a complete set of bright…

Astrophysics · Physics 2009-10-31 Rychard J. Bouwens , Tom Broadhurst , Joseph Silk

In the case of ground-based telescopes equipped with adaptive optics systems, the point spread function (PSF) is only poorly known or completely unknown. Moreover, an accurate modeling of the PSF is in general not available. Therefore in…

Numerical Analysis · Mathematics 2015-06-09 M. Prato , A. La Camera , S. Bonettini , S. Rebegoldi , M. Bertero , P. Boccacci

We present a new probabilistic method for detecting, deblending, and cataloging astronomical sources called the Bayesian Light Source Separator (BLISS). BLISS is based on deep generative models, which embed neural networks within a Bayesian…

Instrumentation and Methods for Astrophysics · Physics 2022-07-13 Derek Hansen , Ismael Mendoza , Runjing Liu , Ziteng Pang , Zhe Zhao , Camille Avestruz , Jeffrey Regier

Active Galactic Nuclei (AGN) are intertwined with galaxy evolution, injecting energy into the interstellar medium (ISM) that could regulate star formation as a galaxy evolves. However, the phenomena through which we observe AGN are…

Aims.The main purpose of this study is to investigate aspects regarding the validity of the active galactic nucleus (AGN) unification paradigm (UP). In particular, we focus on the AGN host galaxies, which according to the UP should show no…

Astrophysics of Galaxies · Physics 2021-09-03 Anamaria Gkini , Manolis Plionis , Maria Chira , Elias Koulouridis

Disentangling the radio flux contribution from star formation (SF) and active-galactic-nuclei (AGN) activity is a long-standing problem in extragalactic astronomy, since at frequencies of $\lesssim$ 10 GHz, both processes emit synchrotron…

With the onset of large-scale astronomical surveys capturing millions of images, there is an increasing need to develop fast and accurate deconvolution algorithms that generalize well to different images. A powerful and accessible…

Instrumentation and Methods for Astrophysics · Physics 2022-11-18 Utsav Akhaury , Jean-Luc Starck , Pascale Jablonka , Frédéric Courbin , Kevin Michalewicz

We present a multi-wavelength study of seven AGN at spectroscopic redshift >2.5 in the 7 Ms Chandra Deep Field South, selected to have good FIR/sub-mm detections. Our aim is to investigate the possibility that the obscuration observed in…

Astrophysics of Galaxies · Physics 2019-04-03 C. Circosta , C. Vignali , R. Gilli , A. Feltre , F. Vito , F. Calura , V. Mainieri , M. Massardi , C. Norman

Astronomical observations of extended sources, such as cubes of integral field spectroscopy (IFS), encode auto-correlated spatial structures that cannot be optimally exploited by standard methodologies. This work introduces a novel…

Instrumentation and Methods for Astrophysics · Physics 2019-01-01 S. González-Gaitán , R. S. de Souza , A. Krone-Martins , E. Cameron , P. Coelho , L. Galbany , E. E. O. Ishida

In the absence of the two emission lines H$\alpha$ and [NII] (6584\AA) in a BPT diagram, we show that other spectral information is sufficiently informative to distinguish AGN galaxies from star-forming galaxies. We use pattern recognition…

Astrophysics of Galaxies · Physics 2018-06-06 Hossen Teimoorinia , Jared Keown

We describe improved modelling of the emission by dust in a toroidal--like structure heated by a central illuminating source within Active Galactic Nuclei (AGN). We chose a simple but realistic torus geometry, a flared disc, and a dust…

Astrophysics · Physics 2009-11-13 J. Fritz , A. Franceschini , E. Hatziminaoglou

We present a model-independent method of quantifying galaxy evolution in high- resolution images, which we apply to the Hubble Deep Field (HDF). Our procedure is to k-correct the pixels belonging to the images of a complete set of bright…

Astrophysics · Physics 2015-06-24 Rychard J. Bouwens , Tom Broadhurst , Joseph Silk

Active Galactic Nuclei often show evidence of photoionized outflows. A major uncertainty in models for these outflows is the distance ($R$) to the gas from the central black hole. In this paper we use the HST/COS data from a massive…

Archival HST/NICMOS-2 images of the Cloverleaf gravitational lens (H1413+117), a quadruply imaged quasar, have been analysed with a new method derived from the MCS deconvolution algorithm (Magain et al., 1998). This method is based on an…

Astrophysics · Physics 2009-11-11 Virginie Chantry , Pierre Magain

AIMS. This work addresses the AGN IR-selection dependency on intrinsic source luminosity and obscuration, in order to identify and charaterise biases which could affect conclusions in studies. METHODS. We study IR-selected AGN in the…

Astrophysics of Galaxies · Physics 2015-06-18 Hugo Messias , Jose M. Afonso , Mara Salvato , Bahram Mobasher , Andrew M. Hopkins