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Computational image reconstruction algorithms generally produce a single image without any measure of uncertainty or confidence. Regularized Maximum Likelihood (RML) and feed-forward deep learning approaches for inverse problems typically…

Machine Learning · Computer Science 2020-12-18 He Sun , Katherine L. Bouman

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

In the near future, new surveys promise a significant increase in the number of quasars (QSO) at large redshifts. This will help to constrain the dark energy models using quasars. The Large Synoptic Survey Telescope (LSST) will cover over…

Astrophysics of Galaxies · Physics 2019-10-08 Mary Loli Martínez-Aldama , Swayamtrupta Panda , Bożena Czerny , Michal Zajaček

Context. Since the advent of modern multiband digital sky surveys, photometric redshifts (photo-z's) have become relevant if not crucial to many fields of observational cosmology, from the characterization of cosmic structures, to weak and…

Instrumentation and Methods for Astrophysics · Physics 2012-10-01 Stefano Cavuoti , Massimo Brescia , Giuseppe Longo , Amata Mercurio

In axion models, interactions between axions and electromagnetic waves induce frequency-dependent time delays determined by the axion mass and decay constant. These small delays are difficult to detect, limiting the effectiveness of…

High Energy Astrophysical Phenomena · Physics 2025-10-29 Haihao Shi , Zhenyang Huang , Qiyu Yan , Jun Li , Guoliang Lü , Xuefei Chen

We used 3.1 million spectroscopically labelled sources from the Sloan Digital Sky Survey (SDSS) to train an optimised random forest classifier using photometry from the SDSS and the Widefield Infrared Survey Explorer (WISE). We applied this…

Astrophysics of Galaxies · Physics 2020-07-15 A. O. Clarke , A. M. M. Scaife , R. Greenhalgh , V. Griguta

We use the 6C** sample to investigate the co-moving space density of powerful, steep-spectrum radio sources. This sample, consisting of 68 objects, has virtually complete K-band photometry and spectroscopic redshifts for 32 per cent of the…

Astrophysics · Physics 2008-11-26 Maria J. Cruz , Matt J. Jarvis , Steve Rawlings , Katherine M. Blundell

The information recoverable from galaxy spectra depends fundamentally on spectral resolution, yet assembling large samples at high resolution remains observationally expensive. We present a deep-learning framework for spectral…

Next generation telescopes, like Euclid, Rubin/LSST, and Roman, will open new windows on the Universe, allowing us to infer physical properties for tens of millions of galaxies. Machine learning methods are increasingly becoming the most…

Astrophysics of Galaxies · Physics 2023-01-05 Euclid Collaboration , L. Bisigello , C. J. Conselice , M. Baes , M. Bolzonella , M. Brescia , S. Cavuoti , O. Cucciati , A. Humphrey , L. K. Hunt , C. Maraston , L. Pozzetti , C. Tortora , S. E. van Mierlo , N. Aghanim , N. Auricchio , M. Baldi , R. Bender , C. Bodendorf , D. Bonino , E. Branchini , J. Brinchmann , S. Camera , V. Capobianco , C. Carbone , J. Carretero , F. J. Castander , M. Castellano , A. Cimatti , G. Congedo , L. Conversi , Y. Copin , L. Corcione , F. Courbin , M. Cropper , A. Da Silva , H. Degaudenzi , M. Douspis , F. Dubath , C. A. J. Duncan , X. Dupac , S. Dusini , S. Farrens , S. Ferriol , M. Frailis , E. Franceschi , P. Franzetti , M. Fumana , B. Garilli , W. Gillard , B. Gillis , C. Giocoli , A. Grazian , F. Grupp , L. Guzzo , S. V. H. Haugan , W. Holmes , F. Hormuth , A. Hornstrup , K. Jahnke , M. Kümmel , S. Kermiche , A. Kiessling , M. Kilbinger , R. Kohley , M. Kunz , H. Kurki-Suonio , S. Ligori , P. B. Lilje , I. Lloro , E. Maiorano , O. Mansutti , O. Marggraf , K. Markovic , F. Marulli , R. Massey , S. Maurogordato , E. Medinaceli , M. Meneghetti , E. Merlin , G. Meylan , M. Moresco , L. Moscardini , E. Munari , S. M. Niemi , C. Padilla , S. Paltani , F. Pasian , K. Pedersen , V. Pettorino , G. Polenta , M. Poncet , L. Popa , F. Raison , A. Renzi , J. Rhodes , G. Riccio , H. -W. Rix , E. Romelli , M. Roncarelli , C. Rosset , E. Rossetti , R. Saglia , D. Sapone , B. Sartoris , P. Schneider , M. Scodeggio , A. Secroun , G. Seidel , C. Sirignano , G. Sirri , L. Stanco , P. Tallada-Crespí , D. Tavagnacco , A. N. Taylor , I. Tereno , R. Toledo-Moreo , F. Torradeflot , I. Tutusaus , E. A. Valentijn , L. Valenziano , T. Vassallo , Y. Wang , A. Zacchei , G. Zamorani , J. Zoubian , S. Andreon , S. Bardelli A. Boucaud , C. Colodro-Conde , D. Di Ferdinando , J. Graciá-Carpio , V. Lindholm , D. Maino , S. Mei , V. Scottez , F. Sureau , M. Tenti , E. Zucca , A. S. Borlaff , M. Ballardini , A. Biviano , E. Bozzo , C. Burigana , R. Cabanac , A. Cappi , C. S. Carvalho , S. Casas , G. Castignani , A. Cooray , J. Coupon , H. M. Courtois , J. Cuby , S. Davini , G. De Lucia , G. Desprez , H. Dole , J. A. Escartin , S. Escoffier , M. Farina , S. Fotopoulou , K. Ganga , J. Garcia-Bellido , K. George , F. Giacomini , G. Gozaliasl , H. Hildebrandt , I. Hook , M. Huertas-Company , V. Kansal , E. Keihanen , C. C. Kirkpatrick , A. Loureiro , J. F. Macías-Pérez , M. Magliocchetti , G. Mainetti , S. Marcin , M. Martinelli , N. Martinet , R. B. Metcalf , P. Monaco , G. Morgante , S. Nadathur , A. A. Nucita , L. Patrizii , A. Peel , D. Potter , A. Pourtsidou , M. Pöntinen , P. Reimberg , A. G. Sánchez , Z. Sakr , M. Schirmer , E. Sefusatti , M. Sereno , J. Stadel , R. Teyssier , C. Valieri , J. Valiviita , M. Viel

In this paper, we explore how the forthcoming generation of large-scale radio continuum surveys, with the inclusion of some degree of redshift information, can constrain cosmological parameters. By cross-matching these radio surveys with…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-20 Stefano Camera , Mário G. Santos , David J. Bacon , Matt J. Jarvis , Kim McAlpine , Ray P. Norris , Alvise Raccanelli , Huub Röttgering

We show how to enhance the redshift accuracy of surveys consisting of tracers with highly uncertain positions along the line of sight. Photometric surveys with redshift uncertainty delta_z ~ 0.03 can yield final redshift uncertainties of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Jens Jasche , Benjamin D. Wandelt

Deep learning methodologies have been employed in several different fields, with an outstanding success in image recognition applications, such as material quality control, medical imaging, autonomous driving, etc. Deep learning models rely…

Computer Vision and Pattern Recognition · Computer Science 2022-03-11 Saul Calderon-Ramirez , Shengxiang Yang , David Elizondo

We have conducted an optical/near-infrared study of the environments of radio-loud quasars (RLQs) at redshifts z=0.6-2. In this paper we discuss the sample selection and observations for the z=1-2 subsample and the reduction and cataloguing…

Astrophysics · Physics 2009-10-30 Patrick B. Hall , Richard F. Green , Martin Cohen

[Abridged] We present reliable multiwavelength identifications and high-quality photometric redshifts for the 462 X-ray sources in the ~2 Ms Chandra Deep Field-South. Source identifications are carried out using deep optical-to-radio…

We present a parameter-decoupled superresolution framework for estimating sub-wavelength separations of passive two-point sources without requiring prior knowledge or control of the source. Our theoretical foundation circumvents the need to…

In many real-world inverse problems, only incomplete measurement data are available for training which can pose a problem for learning a reconstruction function. Indeed, unsupervised learning using a fixed incomplete measurement process is…

Machine Learning · Statistics 2022-09-30 Julián Tachella , Dongdong Chen , Mike Davies

A new approach to estimating photometric redshifts - using Artificial Neural Networks (ANNs) - is investigated. Unlike the standard template-fitting photometric redshift technique, a large spectroscopically-identified training set is…

Astrophysics · Physics 2009-11-07 Andrew E. Firth , Ofer Lahav , Rachel S. Somerville

Extreme deconvolution (XD) of broad-band photometric data can both separate stars from quasars and generate probability density functions for quasar redshifts, while incorporating flux uncertainties and missing data. Mid-infrared…

Astrophysics of Galaxies · Physics 2015-08-06 M. A. DiPompeo , J. Bovy , A. D. Myers , D. Lang

Deep reinforcement learning is an emerging machine learning approach which can teach a computer to learn from their actions and rewards similar to the way humans learn from experience. It offers many advantages in automating decision…

Mesoscale and Nanoscale Physics · Physics 2021-07-08 V. Nguyen , S. B. Orbell , D. T. Lennon , H. Moon , F. Vigneau , L. C. Camenzind , L. Yu , D. M. Zumbühl , G. A. D. Briggs , M. A. Osborne , D. Sejdinovic , N. Ares

Accurate estimation of photometric redshifts (photo-$z$s) is crucial for cosmological surveys. Various methods have been developed for this purpose, such as template fitting methods and machine learning techniques, each with its own…