English
Related papers

Related papers: Creating Spectral Templates from Multicolor Redshi…

200 papers

Calibrating the photometric redshifts of >10^9 galaxies for upcoming weak lensing cosmology experiments is a major challenge for the astrophysics community. The path to obtaining the required spectroscopic redshifts for training and…

We introduce a framework for the enhanced estimation of photometric redshifts using Self-Organising Maps (SOMs). Our method projects galaxy Spectral Energy Distributions (SEDs) onto a two-dimensional map, identifying regions that are…

Obtaining accurate photometric redshift estimations is an important aspect of cosmology, remaining a prerequisite of many analyses. In creating novel methods to produce redshift estimations, there has been a shift towards using machine…

Instrumentation and Methods for Astrophysics · Physics 2021-07-07 Ben Henghes , Connor Pettitt , Jeyan Thiyagalingam , Tony Hey , Ofer Lahav

Large imaging surveys will rely on photometric redshifts (photo-z's), which are typically estimated through machine learning methods. Currently planned spectroscopic surveys will not be deep enough to produce a representative training…

The Wide Field Survey Telescope (WFST) is a dedicated time-domain multi-band ($u$, $g$, $r$, $i$, and $z$) photometric survey facility under construction. In this paper, we present a preliminary study that assesses the quality of…

Cosmology and Nongalactic Astrophysics · Physics 2023-09-06 Yu Liu , Xiao-zhi Lin , Yong-quan Xue , Huynh Anh N. Le

Handling big data has largely been a major bottleneck in traditional statistical models. Consequently, when accurate point prediction is the primary target, machine learning models are often preferred over their statistical counterparts for…

Methodology · Statistics 2021-04-02 Arindam Fadikar , Stefan M. Wild , Jonas Chaves-Montero

We present a combined galaxy-quasar approach to template-fitting photometric redshift techniques and show the method to be a powerful one. The code (ImpZ) is presented, developed and applied to two spectroscopic redshift catalogues, namely…

Broadband time-ordered data obtained from telescopes with a wavelength-dependent, asymmetric beam pattern can be used to extract maps at multiple wavelengths from a single scan. This technique is especially useful when collecting data on…

Instrumentation and Methods for Astrophysics · Physics 2023-06-06 Brianna Cantrall , Solomon Quinn , Emory F. Bunn

Photometric redshift uncertainties are a major source of systematic error for ongoing and future photometric surveys. We study different sources of redshift error caused by choosing a suboptimal redshift histogram bin width and propose…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-02 Markus Michael Rau , Ben Hoyle , Kerstin Paech , Stella Seitz

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…

Instrumentation and Methods for Astrophysics · Physics 2016-12-13 Stefano Cavuoti , Valeria Amaro , Massimo Brescia , Civita Vellucci , Crescenzo Tortora , Giuseppe Longo

Template fits to observed galaxy fluxes allow calculation of K-corrections and conversions among observations of galaxies at various wavelengths. We present a method for creating model-based template sets given a set of heterogeneous…

Astrophysics · Physics 2008-11-26 Michael R. Blanton , Sam Roweis

The next generation of spectroscopic surveys will have a wealth of photometric data available for use in target selection. Selecting the best targets is likely to be one of the most important hurdles in making these spectroscopic campaigns…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 S. Jouvel , F. B. Abdalla , O. Lahav , D. Kirk , H. Lin , J. Annis , R. Kron , J. A. Frieman

The calibration of redshift distributions for photometric samples using spectroscopic surveys is plagued by the difficulty in modelling the selection functions of spectroscopic surveys. In this work, we analyse how these selection functions…

Instrumentation and Methods for Astrophysics · Physics 2022-07-19 Isaac McMahon , Markus Michael Rau , Rachel Mandelbaum

Since the development of photography art, many so-called "templates" have been formed, namely visual styles summarized from a series of themed and stylized photography works. In this paper, we propose to analysize and and summarize these…

Computer Vision and Pattern Recognition · Computer Science 2024-10-10 Xin Jin , Liaoruxing Zhang , Chenyu Fan , Wenbo Yuan

Low redshift surveys of galaxy peculiar velocities provide a wealth of cosmological information. We revisit the idea of extracting this information by directly measuring the redshift-space momentum power spectrum from such surveys. We…

Cosmology and Nongalactic Astrophysics · Physics 2019-06-19 Cullan Howlett

The aim of this paper is to investigate ways to optimize the accuracy of photometric redshifts for a SNAP like mission. We focus on how the accuracy of the photometric redshifts depends on the magnitude limit and signal-to-noise ratio,…

Photometric redshifts (photo-$z$s) are an essential tool for galaxy evolution science with JWST. However, for deep surveys with more limited filter sets (i.e. $N_{\text{filt}} \sim6$) such as large pure parallel surveys, the most commonly…

Astrophysics of Galaxies · Physics 2025-11-07 Kenneth J. Duncan

We showcase machine learning (ML) inspired target selection algorithms to determine which of all potential targets should be selected first for spectroscopic follow up. Efficient target selection can improve the ML redshift uncertainties as…

Instrumentation and Methods for Astrophysics · Physics 2016-06-16 Ben Hoyle , Kerstin Paech , Markus Michael Rau , Stella Seitz , Jochen Weller

Interloper contamination due to line misidentification is an important issue in the future low-resolution spectroscopic surveys. We realize that the algorithm previously used for photometric redshift self-calibration, with minor…

Cosmology and Nongalactic Astrophysics · Physics 2023-09-28 Hui Peng , Yu Yu

The Southern Photometric Local Universe Survey (S-PLUS) is a novel project that aims to map the Southern Hemisphere using a twelve filter system, comprising five broad-band SDSS-like filters and seven narrow-band filters optimized for…