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Related papers: Photometric Redshift Techniques: Reliability and A…

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The article provides a brief survey of the mathematics of some of the newly being developed so called "hybrid" (also called "multi-physics" or "multi-wave") imaging techniques.

Mathematical Physics · Physics 2013-02-25 Peter Kuchment

In this paper we propose to apply copula entropy (CE) to photometric redshifts. CE is used to measure the correlations between photometric measurements and redshifts and then the measurements associated with high CEs are selected for…

Machine Learning · Computer Science 2023-10-26 Jian Ma

Medical image registration is vital for disease diagnosis and treatment with its ability to merge diverse information of images, which may be captured under different times, angles, or modalities. Although several surveys have reviewed the…

Computer Vision and Pattern Recognition · Computer Science 2024-03-26 Qiushi Nie , Xiaoqing Zhang , Yan Hu , Mingdao Gong , Jiang Liu

Accurate optical redshifts will be critical for spectral co-adding techniques used to extract detections from below the noise level in ongoing and upcoming surveys for HI, which will extend our current understanding of gas reservoirs in…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Natasha Maddox , Kelley M. Hess , S. -L. Blyth , M. J. Jarvis

We present a neural network based approach to the determination of photometric redshift. The method was tested on the Sloan Digital Sky Survey Early Data Release (SDSS-EDR) reaching an accuracy comparable and, in some cases, better than SED…

Knowing the redshift of galaxies is one of the first requirements of many cosmological experiments, and as it's impossible to perform spectroscopy for every galaxy being observed, photometric redshift (photo-z) estimations are still of…

Instrumentation and Methods for Astrophysics · Physics 2022-03-09 Ben Henghes , Connor Pettitt , Jeyan Thiyagalingam , Tony Hey , Ofer Lahav

We investigate the expected accuracy of redshifts that can be obtained using low-resolution spectroscopic (medium-band) data from the 7-Dimensional Sky Survey (7DS). By leveraging 40 densely sampled filters with widths of full width at half…

Astrophysics of Galaxies · Physics 2025-10-01 Eunhee Ko , Myungshin Im , Yujin Yang , Ji Hoon Kim , Seong-Kook Lee , Gregory S. -H. Paek

Visible images have been widely used for motion estimation. Thermal images, in contrast, are more challenging to be used in motion estimation since they typically have lower resolution, less texture, and more noise. In this paper, a novel…

Computer Vision and Pattern Recognition · Computer Science 2021-05-18 Weichen Dai , Yu Zhang , Shenzhou Chen , Donglei Sun , Da Kong

In order to retrieve cosmological parameters from photometric surveys, we need to estimate the distribution of the photometric redshift in the sky with excellent accuracy. We use and apply three different machine learning methods to…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-13 Elcio Abdalla , Filipe B. Abdalla , Alessandro Marins , Amilcar Queiroz , Rafael M. Ribeiro , Alex S. C. Souza

Many important computer vision applications are naturally formulated as regression problems. Within medical imaging, accurate regression models have the potential to automate various tasks, helping to lower costs and improve patient…

Machine Learning · Computer Science 2023-11-08 Fredrik K. Gustafsson , Martin Danelljan , Thomas B. Schön

This article discuss the problem of color image content comparison. Particularly, methods of image content comparison are analyzed, restrictions of color histogram are described and a modified method of images content comparison is…

Computer Vision and Pattern Recognition · Computer Science 2018-04-05 Anas M. Al-Oraiqat , Natalya S. Kostyukova

This paper describes a new class of experiments that use dispersion in optical fibers to convert the gravitational frequency shift of light into a measurable phase shift or time delay. Two conceptual models are explored. In the first model,…

General Relativity and Quantum Cosmology · Physics 2009-12-31 Steven Manly , Eric Page

Photometric redshifts (photo-z's) provide an alternative way to estimate the distances of large samples of galaxies and are therefore crucial to a large variety of cosmological problems. Among the various methods proposed over the years,…

Instrumentation and Methods for Astrophysics · Physics 2017-06-13 Stefano Cavuoti , Massimo Brescia , Valeria Amaro , Civita Vellucci , Giuseppe Longo , Crescenzo Tortora

Accurate estimation of photometric redshifts (photo-$z$) is crucial in studies of both galaxy evolution and cosmology using current and future large sky surveys. In this study, we employ Random Forest (RF), a machine learning algorithm, to…

Cosmology and Nongalactic Astrophysics · Physics 2023-12-27 Junhao Lu , Zhijian Luo , Zhu Chen , Liping Fu , Wei Du , Yan Gong , Yicheng Li , Xian-Min Meng , Zhirui Tang , Shaohua Zhang , Chenggang Shu , Xingchen Zhou , Zuhui Fan

We present benchmark problems and solutions for the continuum radiative transfer (RT) in a 2D disk configuration. The reliability of three Monte-Carlo and two grid-based codes is tested by comparing their results for a set of well-defined…

Astrophysics · Physics 2009-11-10 I. Pascucci , S. Wolf , J. Steinacker , C. P. Dullemond , Th. Henning , G. Niccolini , P. Woitke , B. Lopez

A new method is developed for estimating photometric redshifts, using realistic template SEDs, extending over four decades in wavelength (i.e from 0.05 $\mu m$ to 1 mm). The SEDs are constructed for four different spectral types of galaxies…

Astrophysics · Physics 2007-05-23 B. Mobasher , P. Mazzei

We present a description of the observations and data reduction procedures for an extensive spectroscopic and multi-band photometric study of nine high redshift, optically-selected cluster candidates. The primary goal of the survey is to…

Astrophysics · Physics 2009-10-30 J. B. Oke , Marc Postman , Lori Lubin

By means of CCD photometry in three bands (Gunn g, r, i) we investigate the existence of 12 candidate clusters extracted via a model independent peak finding algorithm (\cite{memsait}) from DPOSS data. The derived color-magnitude diagrams…

Astrophysics · Physics 2009-11-07 E. Puddu , S. Andreon , G. Longo , V. Strazzullo , M. Paolillo , R. Gal

Improving distance measurements in large imaging surveys is a major challenge to better reveal the distribution of galaxies on a large scale and to link galaxy properties with their environments. Photometric redshifts can be efficiently…

Redshifts have been so easy to measure for so long that we tend to neglect the fact that they too have uncertainties and are susceptible to systematic error. As we strive to measure cosmological parameters to better than 1% it is worth…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-02 Tamara M. Davis , Samuel R. Hinton , Cullan Howlett , Josh Calcino