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Related papers: The miniJPAS survey quasar selection I: Mock catal…

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Future astrophysical surveys such as J-PAS will produce very large datasets, which will require the deployment of accurate and efficient Machine Learning (ML) methods. In this work, we analyze the miniJPAS survey, which observed about 1…

We present a list of quasar candidates including photometric redshift estimates from the miniJPAS Data Release constructed using SQUEzE. This work is based on machine-learning classification of photometric data of quasar candidates using…

We present a classification-based approach to identify quasi-stellar radio sources (quasars) in the Sloan Digital Sky Survey and evaluate its performance on a manually labeled training set. While reasonable results can already be obtained…

Instrumentation and Methods for Astrophysics · Physics 2016-11-18 Fabian Gieseke , Kai Lars Polsterer , Andreas Thom , Peter-Christian Zinn , Dominik Bomanns , Ralf-Jürgen Dettmar , Oliver Kramer , Jan Vahrenhold

Sophisticated analysis of modern large-scale structure surveys requires mock catalogs. Mock catalogs are used to optimize survey design, test reduction and analysis pipelines, make theoretical predictions for basic observables and propagate…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Martin White , Jeremy L Tinker , Cameron K McBride

We present an algorithm for selecting an uniform sample of gravitationally lensed quasar candidates from low-redshift (0.6<z<2.2) quasars brighter than i=19.1 that have been spectroscopically identified in the SDSS. Our algorithm uses…

Microquasars are ideal natural laboratories for understanding accretion/ejection processes, studying the physics of relativistic jets, and testing gravitational phenomena. Nevertheless, these objects are difficult to find in our Galaxy. The…

Astrophysics · Physics 2009-11-13 J. A. Combi , J. F. Albacete-Colombo , J. Marti

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 explore a variety of statistics of clusters selected with cosmic shear measurement by utilizing both analytic models and large numerical simulations. We first develop a halo model to predict the abundance and the clustering of weak…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-16 Masato Shirasaki , Takashi Hamana , Naoki Yoshida

Reliable extraction of cosmological information from clustering measurements of galaxy surveys requires estimation of the error covariance matrices of observables. The accuracy of covariance matrices is limited by our ability to generate…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-29 Mohammadjavad Vakili , Francisco-Shu Kitaura , Yu Feng , Gustavo Yepes , Cheng Zhao , Chia-Hsun Chuang , ChangHoon Hahn

We use the full-sky ray-tracing weak lensing simulations to generate 2268 mock catalogues for the Subaru Hyper Suprime-Cam (HSC) survey first-year shear catalogue. Our mock catalogues take into account various effects as in the real data:…

Cosmology and Nongalactic Astrophysics · Physics 2019-03-27 Masato Shirasaki , Takashi Hamana , Masahiro Takada , Ryuichi Takahashi , Hironao Miyatake

We describe the algorithm for selecting quasar candidates for optical spectroscopy in the Sloan Digital Sky Survey. Quasar candidates are selected via their non-stellar colors in "ugriz" broad-band photometry, and by matching unresolved…

Context. In modern astronomy, machine learning has proved to be efficient and effective to mine the big data from the newesttelescopes. Spectral surveys enable us to characterize millions of objects, while long exposure time observations…

Cosmic shear is a primary cosmological probe for several present and upcoming surveys investigating dark matter and dark energy, such as Euclid or WFIRST. The probe requires an extremely accurate measurement of the shapes of millions of…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-04 Malte Tewes , Thibault Kuntzer , Reiko Nakajima , Frédéric Courbin , Hendrik Hildebrandt , Tim Schrabback

Massive spectroscopic surveys of high-redshift quasars yield large numbers of correlated Lyman {\alpha} absorption spectra that can be used to measure large-scale structure. Simulations of these surveys are required to accurately interpret…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Andreu Font-Ribera , Patrick McDonald , Jordi Miralda-Escudé

Making mock simulated catalogs is an important component of astrophysical data analysis. Selection criteria for observed astronomical objects are often too complicated to be derived from first principles. However the existence of an…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Amir Hajian , Marcelo Alvarez , J. Richard Bond

This paper presents a comprehensive study of quasar photometric classification and redshift estimation using machine learning techniques. We cross-matched photometric data from the Dark Energy Survey Data Release 2 (DES DR2) with…

Instrumentation and Methods for Astrophysics · Physics 2026-05-19 Pablo Motta , Filipe B. Abdalla , Elcio Abdalla , Gabriel S. Costa , Camila Cardoso
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