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We present BlendHunter, a proof-of-concept for a deep transfer learning based approach for the automated and robust identification of blended sources in galaxy survey data. We take the VGG-16 network with pre-trained convolutional layers…

Instrumentation and Methods for Astrophysics · Physics 2022-01-19 S. Farrens , A. Lacan , A. Guinot , A. Z. Vitorelli

We present Mantis Shrimp, a multi-survey deep learning model for photometric redshift estimation that fuses ultra-violet (GALEX), optical (PanSTARRS), and infrared (UnWISE) imagery. Machine learning is now an established approach for…

Instrumentation and Methods for Astrophysics · Physics 2025-08-01 Andrew Engel , Nell Byler , Adam Tsou , Gautham Narayan , Emmanuel Bonilla , Ian Smith

Quarter sampling is a novel sensor concept that enables the acquisition of higher resolution images without increasing the number of pixels. This is achieved by covering three quarters of each pixel of a low-resolution sensor such that only…

Image and Video Processing · Electrical Eng. & Systems 2022-03-02 Simon Grosche , Kristian Fischer , Fabian Brand , Jürgen Seiler , André Kaup

The Two-Micron All-Sky Survey (2MASS) has mapped out the low-redshift Universe down to $K_S\sim14$ mag. As its near-infrared photometry primarily probes the featureless Rayleigh-Jeans tail of galaxy spectral energy distributions,…

Astrophysics of Galaxies · Physics 2016-02-17 Mubdi Rahman , Brice Ménard , Ryan Scranton

We use a physically motivated semi-analytic model, based on the mass function of dark matter halos, to predict the number of radio-loud quasars as a function of redshift and luminosity. Simple models in which the central BH mass scales with…

Astrophysics · Physics 2009-11-10 Zoltan Haiman , Eliot Quataert , Geoffrey C. Bower

High-redshift quasars typically have their redshift determined from rest-frame ultraviolet (UV) emission lines. However, these lines, and more specifically the prominent C IV $\lambda 1549$ emission line, are typically blueshifted yielding…

Astrophysics of Galaxies · Physics 2020-04-15 Cooper Dix , Ohad Shemmer , Michael S. Brotherton , Richard F. Green , Michelle Mason , Adam D. Myers

The advent of massive broad-band photometric surveys enabled photometric redshift estimates for unprecedented numbers of galaxies and quasars. These estimates can be improved using better algorithms or by obtaining complementary data such…

The Wide-field Infrared Survey Explorer (WISE) has detected hundreds of millions of sources over the entire sky. However, classifying them reliably is a great challenge due to degeneracies in WISE multicolor space and low detection levels…

Instrumentation and Methods for Astrophysics · Physics 2023-07-12 Guiyu Zhao , Bo Qiu , A-Li Luo , Xiaoyu Guo , Lin Yao , Kun Wang , Yuanbo Liu

Physics models typically contain adjustable parameters to reproduce measured data. While some parameters correspond directly to measured features in the data, others are unobservable. These unobservables can, in some cases, cause…

Nuclear Theory · Physics 2024-03-11 C. H. Kim , K. Y. Chae , M. S. Smith , D. W. Bardayan , C. R. Brune , R. J. deBoer , D. Lu , D. Odell

Substances such as chemical compounds are invisible to human eyes, they are usually captured by sensing equipments with their spectral fingerprints. Though spectra of pure chemicals can be identified by visual inspection, the spectra of…

Numerical Analysis · Mathematics 2015-01-07 Yuanchang Sun , Wensong Wu , Jack Xin

Wide-area imaging surveys are one of the key ways of advancing our understanding of cosmology, galaxy formation physics, and the large-scale structure of the Universe in the coming years. These surveys typically require calculating…

Astrophysics of Galaxies · Physics 2020-10-07 P. W. Hatfield , I. A. Almosallam , M. J. Jarvis , N. Adams , R. A. A. Bowler , Z. Gomes , S. J. Roberts , C. Schreiber

In recent years, deep learning has been successfully applied in various scientific domains. Following these promising results and performances, it has recently also started being evaluated in the domain of radio astronomy. In particular,…

In cosmological analyses, precise redshift determination remains pivotal for understanding cosmic evolution. However, with only a fraction of galaxies having spectroscopic redshifts (spec-$z$s), the challenge lies in estimating redshifts…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-04 Anjitha John William , Priyanka Jalan , Maciej Bilicki , Wojciech A. Hellwing

Future cosmological galaxy surveys such as the Large Synoptic Survey Telescope (LSST) will photometrically observe very large numbers of galaxies. Without spectroscopy, the redshifts required for the analysis of these data will need to be…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-07 Daniel M. Jones , Alan F. Heavens

Improving the accuracy of photometric redshifts (photo-$z$) is essential for reliable statistical studies of cosmology and galaxy evolution. However, missing photometric bands are a common observational challenge that can significantly…

We obtain a sample of 87 radio-loud QSOs in the redshift range 3.6<z<4.4 by cross-correlating sources in the FIRST radio survey S{1.4GHz} > 1 mJy with star-like objects having r <20.2 in SDSS Data Release 7. Of these 87 QSOs, 80 are…

Astrophysics of Galaxies · Physics 2015-06-23 D. Tuccillo , J. I. Gonzalez-Serrano , C. R. Benn

We demonstrate that it is possible to measure metallicity from the SDSS five-band photometry to better than 0.1 dex using supervised machine learning algorithms. Using spectroscopic estimates of metallicity as ground truth, we build,…

Instrumentation and Methods for Astrophysics · Physics 2016-01-21 Viviana Acquaviva

In this paper we present near-infrared K-band imaging of a sample of ultra-steep spectrum (USS) radio sources selected at 74 MHz. The dual selection criteria of low frequency and USS means that we should be sensitive to the highest redshift…

Lensed quasars are key to many areas of study in astronomy, offering a unique probe into the intermediate and far universe. However, finding lensed quasars has proved difficult despite significant efforts from large collaborations. These…

We apply a Machine Learning technique known as Convolutional Denoising Autoencoder to denoise synthetic images of state-of-the-art radio telescopes, with the goal of detecting the faint, diffused radio sources predicted to characterise the…

Instrumentation and Methods for Astrophysics · Physics 2021-11-03 Claudio Gheller , Franco Vazza