English
Related papers

Related papers: Imputation of Missing Photometric Data and Photome…

200 papers

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

In this work, we explore methods to improve galaxy redshift predictions by combining different ground truths. Traditional machine learning models rely on training sets with known spectroscopic redshifts, which are precise but only represent…

Instrumentation and Methods for Astrophysics · Physics 2024-11-28 Jonathan Soriano , Srinath Saikrishnan , Vikram Seenivasan , Bernie Boscoe , Jack Singal , Tuan Do

We present forecasts for the $E_G$ statistic using redshift distributions of realistic mock galaxy samples from the upcoming Chinese Space Station Survey Telescope (CSST). The dominant uncertainty in $E_G$ stems from the redshift space…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-27 Yu Song , Yi Zheng

We consider the possibility that the Gaia mission can supply data which will improve the photometric calibration of LSST. After outlining the LSST calibra- tion process and the information that will be available from Gaia, we explore two…

Instrumentation and Methods for Astrophysics · Physics 2016-06-30 Tim Axelrod , Calder Miller

We use the mock catalog of galaxies, constructed based on the COSMOS galaxy catalog including information on photometric redshifts (photo-z) and SED types of galaxies, in order to study how to define a galaxy subsample suitable for weak…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Atsushi J. Nishizawa , Masahiro Takada , Takashi Hamana , Hisanori Furusawa

We conduct a detailed analysis of the photometric redshift requirements for the proposed Dark Energy Survey (DES) using two sets of mock galaxy simulations and an artificial neural network code - ANNz. In particular, we examine how optical…

Astrophysics · Physics 2010-03-26 Manda Banerji , Filipe B. Abdalla , Ofer Lahav , Huan Lin

Time series data are ubiquitous in real-world applications. However, one of the most common problems is that the time series data could have missing values by the inherent nature of the data collection process. So imputing missing values…

Machine Learning · Computer Science 2022-09-23 Eunkyu Oh , Taehun Kim , Yunhu Ji , Sushil Khyalia

In this paper we apply ideas from information theory to create a method for the design of optimal filters for photometric redshift estimation. We show the method applied to a series of simple example filters in order to motivate an…

Instrumentation and Methods for Astrophysics · Physics 2021-01-27 J. Bryce Kalmbach , Jacob T. VanderPlas , Andrew J. Connolly

Wide field images taken in several photometric bands allow simultaneous measurement of redshifts for thousands of galaxies. A variety of algorithms to make this measurement have appeared in the last few years, the majority of which can be…

Cosmology and Nongalactic Astrophysics · Physics 2016-05-11 Juan De Vicente , Eusebio Sánchez , Ignacio Sevilla

Photometric redshifts (photo-$z$'s) are crucial for the cosmology, galaxy evolution, and transient science drivers of next-generation imaging facilities like the Euclid Mission, the Rubin Observatory, and the Nancy Grace Roman Space…

Astrophysics of Galaxies · Physics 2025-12-03 Emma R. Moran , Brett H. Andrews , Jeffrey A. Newman , Biprateep Dey

Accurate and reliable photometric redshift determination is one of the key aspects for wide-field photometric surveys. Determination of photometric redshift for galaxies, has been traditionally solved by use of machine-learning and…

Instrumentation and Methods for Astrophysics · Physics 2025-07-18 M. Garcia-Fernandez

We calculate photometric redshifts from the Sloan Digital Sky Survey Main Galaxy Sample, The Galaxy Evolution Explorer All Sky Survey, and The Two Micron All Sky Survey using two new training-set methods. We utilize the broad-band…

Astrophysics · Physics 2008-11-26 M. J. Way , A. N. Srivastava

The Chinese Space Station Survey Telescope (CSST) aims to map the universe across an unprecedented dynamic range of stellar densities, spanning from extragalactic voids to the crowded Galactic center (e.g. a few stars and galaxies in the…

Instrumentation and Methods for Astrophysics · Physics 2026-05-19 Jinzhi Lai , Man I Lam , Jianjun Chen , Xin Zhang , Hao Tian , Xiaohan Chen , Jialu Nie , Ming Yang , Chao Liu

Photometric redshifts (photo-$z$'s) will be crucial for studies of galaxy evolution, large-scale structure, and transients with the Nancy Grace Roman Space Telescope. Deep learning methods leverage pixel-level information from ground-based…

Instrumentation and Methods for Astrophysics · Physics 2026-05-14 Ashod Khederlarian , Brett H. Andrews , Jeffrey A. Newman , Tianqing Zhang , Biprateep Dey

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

Cosmic shear is regarded one of the most powerful probes to reveal the properties of dark matter and dark energy. To fully utilize its potential, one has to be able to control systematic effects down to below the level of the statistical…

Cosmology and Nongalactic Astrophysics · Physics 2010-02-03 B. Joachimi , P. Schneider

A goal of forthcoming imaging surveys is to use weak gravitational lensing shear measurements to constrain dark energy. We quantify the importance of uncalibrated photometric redshift outliers to the dark energy goals of forthcoming imaging…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-13 Andrew P. Hearin , Andrew R. Zentner , Zhaoming Ma , Dragan Huterer

We use simulations to demonstrate that photometric redshift "errors" can be greatly reduced by using the photometric redshift probability distribution p(z) rather than a one-point estimate such as the most likely redshift. In principle this…

Cosmology and Nongalactic Astrophysics · Physics 2009-08-03 D. Wittman

We study how the addition of on-board optical photometric bands to future space-based weak lensing instruments could affect the photometric redshift estimation of galaxies, and hence improve estimations of the dark energy parameters through…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Robert Sorba , Marcin Sawicki