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Related papers: Mixture Models for Photometric Redshifts

200 papers

Current and future weak lensing surveys will rely on photometrically estimated redshifts of very large numbers of galaxies. In this paper, we address several different aspects of the demanding photo-z performance that will be required for…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Rongmon Bordoloi , Simon J. Lilly , Adam Amara

We present photometric redshifts for 1,031 X-ray sources in the X-ATLAS field, using the machine learning technique TPZ (Carrasco Kind & Brunner 2013). X-ATLAS covers 7.1 deg2 observed with the XMM-Newton within the Science Demonstration…

Astrophysics of Galaxies · Physics 2017-12-06 G. Mountrichas , A. Corral , V. A. Masoura , I. Georgantopoulos , A. Ruiz , A. Georgakakis , F. J. Carrera , S. Fotopoulou

We present a method, PhotoWeb, for estimating photometric redshifts of individual galaxies, and their equivalent distance, with megaparsec and even sub-megaparsec accuracy using the Cosmic Web as a constraint over photo-z estimates.…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-30 Miguel A. Aragon-Calvo , Rien van de Weygaert , Bernard J. T. Jones , Bahram Mobasher

Around $10^5$ strongly lensed galaxies are expected to be discovered with Euclid and the LSST. Utilising these large samples to study the inner structure of lens galaxies requires source redshifts, to turn lens models into mass…

Cosmology and Nongalactic Astrophysics · Physics 2023-02-01 Danial Langeroodi , Alessandro Sonnenfeld , Henk Hoekstra , Adriano Agnello

We present a machine-learning photometric redshift analysis of the Kilo-Degree Survey Data Release 3, using two neural-network based techniques: ANNz2 and MLPQNA. Despite limited coverage of spectroscopic training sets, these ML codes…

We present a study of photometric redshift accuracy in the 3D-HST photometric catalogs, using 3D-HST grism redshifts to quantify and dissect trends in redshift accuracy for galaxies brighter than $H_{F140W}<24$ with an unprecedented and…

Photometric redshifts will be a key data product for the Rubin Observatory Legacy Survey of Space and Time (LSST) as well as for future ground and space-based surveys. The need for photometric redshifts, or photo-zs, arises from sparse…

(Abridged) In this paper we present photometric redshift estimates for a sample of X-ray selected sources detected in the wide field (~2 deg^2), bright [f_{X} (0.5-8 keV)~10^{-14} cgs] XMM-Newton/2dF survey. Unlike deeper X-ray samples…

Astrophysics · Physics 2008-11-26 S. Kitsionas , E. Hatziminaoglou , A. Georgakakis , I. Georgantopoulos

Accurate photometric redshifts are a lynchpin for many future experiments to pin down the cosmological model and for studies of galaxy evolution. In this study, a novel sparse regression framework for photometric redshift estimation is…

Instrumentation and Methods for Astrophysics · Physics 2025-06-03 Ibrahim A. Almosallam , Sam N. Lindsay , Matt J. Jarvis , Stephen J. Roberts

Despite the high accuracy of photometric redshifts (zphot) derived using Machine Learning (ML) methods, the quantification of errors through reliable and accurate Probability Density Functions (PDFs) is still an open problem. First, because…

Wide, deep photometric surveys require robust photometric redshift estimates (photo-z's) for studies of large-scale structure. These estimates depend critically on accurate photometry. We describe the improvements to the photometric…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Samuel J. Schmidt , Paul Thorman

We present a robust method to estimate the redshift of galaxies using Pan-STARRS1 photometric data. Our method is an adaptation of the one proposed by Beck et al. (2016) for the SDSS Data Release 12. It uses a training set of 2313724…

Astrophysics of Galaxies · Physics 2020-10-14 Paula Tarrío , Stefano Zarattini

Photometric redshift (photo-z) estimates are playing an increasingly important role in extragalactic astronomy and cosmology. Crucial to many photo-z applications is the accurate quantification of photometric redshift errors and their…

Astrophysics · Physics 2010-11-11 Hiroaki Oyaizu , Marcos Lima , Carlos E. Cunha , Huan Lin , Joshua Frieman

Measuring distances of cosmological sources such as galaxies, stars and quasars plays an increasingly critical role in modern cosmology. Obtaining the optical spectrum and consequently calculating the redshift as a distance indicator could…

Astrophysics of Galaxies · Physics 2022-01-13 Aidin Momtaz , Mohammad Hossein Salimi , Soroush Shakeri

In Lima et al. 2008 we presented a new method for estimating the redshift distribution, N(z), of a photometric galaxy sample, using photometric observables and weighted sampling from a spectroscopic subsample of the data. In this paper, we…

Astrophysics · Physics 2010-03-18 Carlos E. Cunha , Marcos Lima , Hiroaki Oyaizu , Joshua Frieman , Huan Lin

We use SDSS photometry of 73 million stars to simultaneously obtain best-fit main-sequence stellar energy distribution (SED) and amount of dust extinction along the line of sight towards each star. Using a subsample of 23 million stars with…

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

We present redshift probability distributions for galaxies in the SDSS DR8 imaging data. We used the nearest-neighbor weighting algorithm presented in Lima et al. 2008 and Cunha et al. 2009 to derive the ensemble redshift distribution N(z),…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Erin S. Sheldon , Carlos Cunha , Rachel Mandelbaum , J. Brinkmann , Benjamin A. Weaver