English
Related papers

Related papers: Photometric redshift estimation based on data mini…

200 papers

In order to answer the open questions of modern cosmology and galaxy evolution theory, robust algorithms for calculating photometric redshifts (photo-z) for very large samples of galaxies are needed. Correct estimation of the various…

Instrumentation and Methods for Astrophysics · Physics 2021-08-25 Oleksandra Razim , Stefano Cavuoti , Massimo Brescia , Giuseppe Riccio , Mara Salvato , Giuseppe Longo

We present the first systematic analysis of photometric redshifts (photo-z) estimated from the Rubin Observatory Data Preview 1 (DP1) data taken with the Legacy Survey of Space and Time (LSST) Commissioning Camera. Employing the Redshift…

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…

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

We present an unsupervised machine learning approach that can be employed for estimating photometric redshifts. The proposed method is based on a vector quantization approach called Self--Organizing Mapping (SOM). A variety of…

Instrumentation and Methods for Astrophysics · Physics 2015-06-03 M. J. Way , C. D. Klose

Machine learning photo-z methods, trained directly on spectroscopic redshifts, provide a viable alternative to traditional template fitting methods but may not generalise well on new data that deviates from that in the training set. In this…

Instrumentation and Methods for Astrophysics · Physics 2024-02-02 Shingo Tanigawa , Karl Glazebrook , Colin Jacobs , Ivo Labbe , Alex K. Qin

The need to analyze the available large synoptic multi-band surveys drives the development of new data-analysis methods. Photometric redshift estimation is one field of application where such new methods improved the results, substantially.…

Instrumentation and Methods for Astrophysics · Physics 2018-01-31 Antonio D'Isanto , Kai Lars Polsterer

In cosmological analyses, precise redshift determination remains pivotal for understanding cosmic evolution. However, with only a fraction of galaxies having spectroscopic redshifts (spec-$z$s), the challenge lies in estimating redshifts…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-04 Anjitha John William , Priyanka Jalan , Maciej Bilicki , Wojciech A. Hellwing

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 ANNz2, a new implementation of the public software for photometric redshift (photo-z) estimation of Collister and Lahav (2004), which now includes generation of full probability distribution functions (PDFs). ANNz2 utilizes…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-24 Iftach Sadeh , Filipe B. Abdalla , Ofer Lahav

Redshift is a key quantity for inferring cosmological model parameters. In photometric redshift estimation, cosmologists use the coarse data collected from the vast majority of galaxies to predict the redshift of individual galaxies. To…

Applications · Statistics 2016-04-07 Rafael Izbicki , Ann B. Lee , Peter E. Freeman

The importance of photometric galaxy redshift estimation is rapidly increasing with the development of specialised powerful observational facilities. We develop a new photometric redshift estimation workflow TOPz to provide reliable and…

The need for accurate photometric redshifts estimation is a topic that has fundamental importance in Astronomy, due to the necessity of efficiently obtaining redshift information without the need of spectroscopic analysis. We propose a…

Instrumentation and Methods for Astrophysics · Physics 2017-06-14 Antonio D'Isanto

We describe a new program for determining photometric redshifts, dubbed EAZY. The program is optimized for cases where spectroscopic redshifts are not available, or only available for a biased subset of the galaxies. The code combines…

Astrophysics · Physics 2009-11-13 Gabriel B. Brammer , Pieter G. van Dokkum , Paolo Coppi

We present a new machine learning model for estimating photometric redshifts with improved accuracy for galaxies in Pan-STARRS1 data release 1. Depending on the estimation range of redshifts, this model based on neural networks can handle…

Instrumentation and Methods for Astrophysics · Physics 2021-12-09 Joongoo Lee , Min-Su Shin

Accurate redshift estimates are a vital component in understanding galaxy evolution and precision cosmology. In this paper, we explore approaches to increase the applicability of machine learning models for photometric redshift estimation…

Instrumentation and Methods for Astrophysics · Physics 2026-01-27 Jonathan Soriano , Tuan Do , Srinath Saikrishnan , Vikram Seenivasan , Bernie Boscoe , Jack Singal , Evan Jones

We present a photometric redshift (photo-$z$) estimation technique for galaxies in the P\lowercase{an}-STARRS1 (PS1) $3\pi $ survey. Specifically, we train and test a regression and a classification Random-Forest (RF) models using…

Astrophysics of Galaxies · Physics 2021-05-28 A. Baldeschi , M. Stroh , R. Margutti , T. Laskar , A. Miller

Based on the SDSS and SDSS-WISE quasar datasets, we put forward two schemes to estimate the photometric redshifts of quasars. Our schemes are based on the idea that the samples are firstly classified into subsamples by a classifier and then…

Instrumentation and Methods for Astrophysics · Physics 2019-12-05 Yanxia Zhang , Jingyi Zhang , Xin Jin , Yongheng Zhao

In the modern galaxy surveys photometric redshifts play a central role in a broad range of studies, from gravitational lensing and dark matter distribution to galaxy evolution. Using a dataset of about 25,000 galaxies from the second data…

Instrumentation and Methods for Astrophysics · Physics 2017-06-14 Stefano Cavuoti , Crescenzo Tortora , Massimo Brescia , Giuseppe Longo , Mario Radovich , Nicola R. Napolitano , Valeria Amaro , Civita Vellucci

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