English
Related papers

Related papers: Deriving Photometric Redshifts using Fuzzy Archety…

200 papers

Recovering credible cosmological parameter constraints in a weak lensing shear analysis requires an accurate model that can be used to marginalize over nuisance parameters describing potential sources of systematic uncertainty, such as the…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-20 Tianqing Zhang , Markus Michael Rau , Rachel Mandelbaum , Xiangchong Li , Ben Moews

We use the full-sky ray-tracing weak lensing simulations to generate 2268 mock catalogues for the Subaru Hyper Suprime-Cam (HSC) survey first-year shear catalogue. Our mock catalogues take into account various effects as in the real data:…

Cosmology and Nongalactic Astrophysics · Physics 2019-03-27 Masato Shirasaki , Takashi Hamana , Masahiro Takada , Ryuichi Takahashi , Hironao Miyatake

The observing strategy of a galaxy survey influences the degree to which its resulting data can be used to accomplish any science goal. LSST is thus seeking metrics of observing strategies for multiple science cases in order to optimally…

Instrumentation and Methods for Astrophysics · Physics 2021-04-19 Alex I. Malz , François Lanusse , John Franklin Crenshaw , Melissa L. Graham

Photometric redshifts are essential in studies of both galaxy evolution and cosmology, as they enable analyses of objects too numerous or faint for spectroscopy. The Rubin Observatory, Euclid, and Roman Space Telescope will soon provide a…

Cosmology and Nongalactic Astrophysics · Physics 2022-10-28 Jeffrey A. Newman , Daniel Gruen

We examine a general framework for visualizing datasets of high (> 2) dimensionality, and demonstrate it using the morphology of galaxies at moderate redshifts. The distributions of various populations of such galaxies are examined in a…

Astrophysics · Physics 2007-05-23 A. Naim , K. U. Ratnatunga , R. E. Griffiths

An accurate calibration of the source redshift distribution $p(z)$ is a key aspect in the analysis of cosmic shear data. This, one way or another, requires the use of spectroscopic or high-quality photometric samples. However, the…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-25 Carlos García-García , David Alonso , Pedro G. Ferreira , Boryana Hadzhiyska , Andrina Nicola , Carles Sánchez , Anže Slosar

We present a data-driven method to infer the redshift distribution of an arbitrary dataset based on spatial cross-correlation with a reference population and we apply it to various datasets across the electromagnetic spectrum to show its…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-31 Brice Ménard , Ryan Scranton , Samuel Schmidt , Chris Morrison , Donghui Jeong , Tamas Budavari , Mubdi Rahman

We investigate the potential and accuracy of clustering-based redshift estimation using the method proposed by M\'enard et al. (2013). This technique enables the inference of redshift distributions from measurements of the spatial…

Astrophysics of Galaxies · Physics 2015-06-22 Mubdi Rahman , Brice Ménard , Ryan Scranton , Samuel J. Schmidt , Christopher B. Morrison

In the era of large sky surveys, photometric redshifts (photo-z) represent crucial information for galaxy evolution and cosmology studies. In this work, we propose a new Machine Learning (ML) tool called Galaxy morphoto-Z with neural…

We describe a new method (Poisson Probability Method, PPM) to search for high redshift galaxy clusters and groups by using photometric redshift information and galaxy number counts. The method relies on Poisson statistics and is primarily…

Astrophysics of Galaxies · Physics 2015-06-19 Gianluca Castignani , Marco Chiaberge , Annalisa Celotti , Colin Norman

We present a flexible template-based photometric redshift estimation framework, implemented in C#, that can be seamlessly integrated into a SQL database (or DB) server and executed on-demand in SQL. The DB integration eliminates the need to…

Astrophysics of Galaxies · Physics 2017-03-21 Róbert Beck , László Dobos , Tamás Budavári , Alexander S. Szalay , István Csabai

The technique of estimating redshifts using photometric rather than spectroscopic observations has recently received great attention due to its simplicity and the accuracy of the results obtained. In this work, we estimate photometric…

Astrophysics · Physics 2007-05-23 S. Kitsionas , E. Hatziminaoglou , I. Georgantopoulos , A. Georgakakis , O. Giannakis

We present a method to simulate color, 3-dimensional images taken with a space-based observatory by building off of the established shapelets pipeline. The simulated galaxies exhibit complex morphologies, which are realistically correlated…

Astrophysics · Physics 2009-08-18 M. Ferry , J. Rhodes , R. Massey , M. White , D. Coe , B. Mobasher

We present methods to (i) graphically identify robust redshifts using emission lines in the (sub)mm regime, (ii) evaluate the capabilities of different (sub)mm practices for measuring spectroscopic redshifts, and (iii) optimise future…

Instrumentation and Methods for Astrophysics · Physics 2022-05-25 Tom J. L. C. Bakx , Helmut Dannerbauer

In addition to the maximum likelihood approach, there are two other methods which are commonly used to reconstruct the true redshift distribution from photometric redshift datasets: one uses a deconvolution method, and the other a…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Ravi K. Sheth , Graziano Rossi

We present a photometric method for identifying stars, galaxies and quasars in multi-color surveys and estimating multi-color redshifts for the extragalactic objects. We use a library of >65000 color templates for comparison with observed…

Astrophysics · Physics 2009-10-31 Christian Wolf , Klaus Meisenheimer , Hermann-Josef Röser

We present a comparison between the spectroscopic catalog of the HDF recently published by Cohen et al and the redshifts measured by our group for those objects using photometric techniques. We perform this comparison in order to…

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

Based on the Sloan Digital Sky Survey Data Release 5 Galaxy Sample, we explore photometric morphology classification and redshift estimation of galaxies using photometric data and known spectroscopic redshifts. An unsupervised method,…

Astrophysics · Physics 2009-11-13 Yanxia Zhang , Lili Li , Yongheng Zhao