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相关论文: Characterising Improvements in Photometric Redshif…

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We conduct a comprehensive study of the effects of incorporating galaxy morphology information in photometric redshift estimation. Using machine learning methods, we assess the changes in the scatter and catastrophic outlier fraction of…

Photometric surveys produce large-area maps of the galaxy distribution, but with less accurate redshift information than is obtained from spectroscopic methods. Modern photometric redshift (photo-z) algorithms use galaxy magnitudes, or…

宇宙学与河外天体物理 · 物理学 2016-06-15 J. Asorey , M. Carrasco Kind , I. Sevilla-Noarbe , R. J. Brunner , J. Thaler

This study aims to improve the photometric redshifts (photo-$z$s) of galaxies by integrating two contemporary methods: template-fitting and machine learning. Finding the synergy between these two methods was not a high priority in the past,…

宇宙学与河外天体物理 · 物理学 2023-11-30 Ishaq Y. K. Alshuaili , John Y. H. Soo , Mohd Zubir Mat Jafri , Yasmin Rafid

In the present study, we use the DES Y3 catalog of LRG to incorporate the realistic galaxies' redshift Probability Distribution Function(PDF) into the correlation function cosmological model. We used four different photo-z estimators ANNz2,…

宇宙学与河外天体物理 · 物理学 2026-04-06 Paula S. Ferreira , Ribamar R. R. Reis

We present a determination of the effects of including galaxy morphological parameters in photometric redshift estimation with an artificial neural network method. Neural networks, which recognize patterns in the information content of data…

宇宙学与河外天体物理 · 物理学 2015-05-27 J. Singal , M. Shmakova , B. Gerke , R. L. Griffith , J. Lotz

We apply machine learning in the form of a nearest neighbor instance-based algorithm (NN) to generate full photometric redshift probability density functions (PDFs) for objects in the Fifth Data Release of the Sloan Digital Sky Survey (SDSS…

We developed a Deep Convolutional Neural Network (CNN), used as a classifier, to estimate photometric redshifts and associated probability distribution functions (PDF) for galaxies in the Main Galaxy Sample of the Sloan Digital Sky Survey…

天体物理仪器与方法 · 物理学 2018-12-26 Johanna Pasquet , Emmanuel Bertin , Marie Treyer , Stéphane Arnouts , Dominique Fouchez

A variety of fundamental astrophysical science topics require the determination of very accurate photometric redshifts (photo-z's). A wide plethora of methods have been developed, based either on template models fitting or on empirical…

天体物理仪器与方法 · 物理学 2016-12-13 Stefano Cavuoti , Valeria Amaro , Massimo Brescia , Civita Vellucci , Crescenzo Tortora , Giuseppe Longo

Galaxy photometric redshift (photo-$z$) is crucial in cosmological studies, such as weak gravitational lensing and galaxy angular clustering measurements. In this work, we try to extract photo-$z$ information and construct its probability…

宇宙学与河外天体物理 · 物理学 2022-11-16 Xingchen Zhou , Yan Gong , Xian-Min Meng , Xuelei Chen , Zhu Chen , Wei Du , Liping Fu , Zhijian Luo

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…

We have carried a detailed analysis on the impact of cosmological redshift in the non-parametric approach to automated galaxy morphology classification. We artificially redshifted each galaxy from the EFIGI 4458 sample (re-centred at $z…

星系天体物理 · 物理学 2018-12-04 Leonardo de Albernaz Ferreira , Fabricio Ferrari

Many scientific investigations of photometric galaxy surveys require redshift estimates, whose uncertainty properties are best encapsulated by photometric redshift (photo-z) posterior probability density functions (PDFs). A plethora of…

We introduce an ordinal classification algorithm for photometric redshift estimation, which significantly improves the reconstruction of photometric redshift probability density functions (PDFs) for individual galaxies and galaxy samples.…

宇宙学与河外天体物理 · 物理学 2015-07-20 Markus Michael Rau , Stella Seitz , Fabrice Brimioulle , Eibe Frank , Oliver Friedrich , Daniel Gruen , Ben Hoyle

Precision photometric redshifts will be essential for extracting cosmological parameters from the next generation of wide-area imaging surveys. In this paper we introduce a photometric redshift algorithm, ArborZ, based on the…

宇宙学与河外天体物理 · 物理学 2010-05-06 David W. Gerdes , Adam J. Sypniewski , Timothy A. McKay , Jiangang Hao , Matthew R. Weis , Risa H. Wechsler , Michael T. Busha

Galaxy morphology is one of the most fundamental ways to describe galaxy properties, but the morphology we observe may be affected by wavelength and spatial resolution, which may introduce systematic bias when comparing galaxies at…

星系天体物理 · 物理学 2023-07-27 Yao Yao , Jie Song , Xu Kong , Guanwen Fang , Hong-Xin Zhang , Xinkai Chen

Photometric galaxy surveys are an essential tool to further our understanding of the large-scale structure of the universe, its matter and energy content and its evolution. These surveys necessitate the determination of the galaxy redshifts…

宇宙学与河外天体物理 · 物理学 2014-02-06 Pol Martí , Ramon Miquel , Anne Bauer , Enrique Gaztañaga

Modern galaxy surveys produce redshift probability density functions (PDFs) in addition to traditional photometric redshift (photo-$z$) point estimates. However, the storage of photo-$z$ PDFs may present a challenge with increasingly large…

天体物理仪器与方法 · 物理学 2021-08-03 A. I. Malz , P. J. Marshall , S. J. Schmidt , M. L. Graham , J. DeRose , R. Wechsler

Many astrophysical analyses depend on estimates of redshifts (a proxy for distance) determined from photometric (i.e., imaging) data alone. Inaccurate estimates of photometric redshift uncertainties can result in large systematic errors.…

天体物理仪器与方法 · 物理学 2022-05-31 Biprateep Dey , Jeffrey A. Newman , Brett H. Andrews , Rafael Izbicki , Ann B. Lee , David Zhao , Markus Michael Rau , Alex I. Malz

Although photometric redshifts (photo-z's) are crucial ingredients for current and upcoming large-scale surveys, the high-quality spectroscopic redshifts currently available to train, validate, and test them are substantially…

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