English
Related papers

Related papers: Augmenting photometric redshift estimates using sp…

200 papers

We present redshift probability distributions for galaxies in the SDSS DR8 imaging data. We used the nearest-neighbor weighting algorithm presented in Lima et al. 2008 and Cunha et al. 2009 to derive the ensemble redshift distribution N(z),…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Erin S. Sheldon , Carlos Cunha , Rachel Mandelbaum , J. Brinkmann , Benjamin A. Weaver

We explore the accuracy of the clustering-based redshift estimation proposed by M\'enard et al. (2013) when applied to VIPERS and CFHTLS real data. This method enables us to reconstruct redshift distributions from measurement of the angular…

We develop a novel method to explore the galaxy-halo connection using the galaxy imaging surveys by modeling the projected two-point correlation function measured from the galaxies with reasonable photometric redshift measurements. By…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-17 Zhaoyu Wang , Haojie Xu , Xiaohu Yang , Y. P. Jing , Hong Guo , Zheng Zheng , Ying Zu , Zhigang Li , Chengze Liu

The Red-Sequence Cluster Survey (RCS) provides a large and deep photometric catalog of galaxies in the $z'$ and $R_c$ bands for ~90 square degrees of sky, and supplemental $V$ and $B$ data have been obtained for 33.6 deg$^{2}$. We compile a…

Astrophysics · Physics 2009-11-10 B. C. Hsieh , H. K. C. Yee , H. Lin , M. D. Gladders

Galaxy cluster centring is a key issue for precision cosmology studies using galaxy surveys. Mis-identification of central galaxies causes systematics in various studies such as cluster lensing, satellite kinematics, and galaxy clustering.…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-07 Chiaki Hikage , Rachel Mandelbaum , Alexie Leauthaud , Eduardo Rozo , Eli S. Rykoff

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

In order to study the galaxy population of galaxy clusters with photometric data one must be able to accurately discriminate between cluster members and non-members. The redMaPPer cluster finding algorithm treats this problem…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-19 Eduardo Rozo , Eli S. Rykoff , Matthew Becker , Rachel M. Reddick , Risa H. Wechsler

We use a contrastive self-supervised learning framework to estimate distances to galaxies from their photometric images. We incorporate data augmentations from computer vision as well as an application-specific augmentation accounting for…

Instrumentation and Methods for Astrophysics · Physics 2021-01-13 Md Abul Hayat , Peter Harrington , George Stein , Zarija Lukić , Mustafa Mustafa

The number density of galaxy clusters across mass and redshift has been established as a powerful cosmological probe. Cosmological analyses with galaxy clusters traditionally employ scaling relations. However, many challenges arise from…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-08 M. Kosiba , N. Cerardi , M. Pierre , F. Lanusse , C. Garrel , N. Werner , M. Shalak

Photometric galaxy surveys constitute a powerful cosmological probe but rely on the accurate characterization of their redshift distributions using only broadband imaging, and can be very sensitive to incomplete or biased priors used for…

Cosmology and Nongalactic Astrophysics · Physics 2020-09-30 Alex Alarcon , Carles Sánchez , Gary M. Bernstein , Enrique Gaztañaga

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

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

Measuring distances of cosmological sources such as galaxies, stars and quasars plays an increasingly critical role in modern cosmology. Obtaining the optical spectrum and consequently calculating the redshift as a distance indicator could…

Astrophysics of Galaxies · Physics 2022-01-13 Aidin Momtaz , Mohammad Hossein Salimi , Soroush Shakeri

Aims. Using the VIMOS Public Extragalactic Redshift Survey (VIPERS) we aim to jointly estimate the key parameters that describe the galaxy density field and its spatial correlations in redshift space. Methods. We use the Bayesian formalism…

We explore the enhanced self-calibration of photometric galaxy redshift distributions, $n(z)$, through the combination of up to six two-point functions. Our $\rm 3\times2pt$ configuration is comprised of photometric shear, spectroscopic…

WL measurements have well-known shear estimation biases, which can be partially corrected for with the use of image simulations. We present an analysis of simulated images that mimic HST/ACS observations of high-redshift galaxy clusters,…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-26 B. Hernandez-Martin , T. Schrabback , H. Hoekstra , N. Martinet , J. Hlavacek-Larrondo , L. E. Bleem , M. D. Gladders , B. Stalder , A. A. Stark , M. Bayliss

We compile a sample of spectroscopically- and photometrically-selected cluster galaxies from four high-redshift galaxy clusters ($1.59 < z < 1.71$) from the Spitzer Adaptation of the Red-Sequence Cluster Survey (SpARCS), and a comparison…

In Lima et al. 2008 we presented a new method for estimating the redshift distribution, N(z), of a photometric galaxy sample, using photometric observables and weighted sampling from a spectroscopic subsample of the data. In this paper, we…

Astrophysics · Physics 2010-03-18 Carlos E. Cunha , Marcos Lima , Hiroaki Oyaizu , Joshua Frieman , Huan Lin

The use of photometric redshifts in cosmology is increasing. Often, however these photo-zs are treated like spectroscopic observations, in that the peak of the photometric redshift, rather than the full probability density function (PDF),…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Adam D Myers , Martin White , Nicholas M. Ball

Accurately characterizing the redshift distributions of galaxies is essential for analysing deep photometric surveys and testing cosmological models. We present a technique to simultaneously infer redshift distributions and individual…

Cosmology and Nongalactic Astrophysics · Physics 2016-07-27 Boris Leistedt , Daniel J. Mortlock , Hiranya V. Peiris