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Related papers: Implementation of PhotoZ under Astro-WISE - A phot…

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This study aims to improve the photometric redshifts (photo-$z$s) of galaxies by integrating two contemporary methods: template-fitting and machine learning. Finding the synergy between these two methods was not a high priority in the past,…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-30 Ishaq Y. K. Alshuaili , John Y. H. Soo , Mohd Zubir Mat Jafri , Yasmin Rafid

Spectral modeling codes that estimate photometric redshifts (photo-$z$) are a powerful and often reliable method for determining redshifts of galaxies. However, there are notable instances where degeneracies in spectral energy distribution…

Astrophysics of Galaxies · Physics 2025-07-03 A. J. Battisti , E. da Cunha , S. Jin , J. A. Hodge

We present a novel approach to quality control during the processing of astronomical data. Quality control in the Astro-WISE Information System is integral to all aspects of data handing and provides transparent access to quality estimators…

Instrumentation and Methods for Astrophysics · Physics 2012-03-27 J. P. McFarland , E. M. Helmich , E. A. Valentijn

Over 3 billion astronomical objects have been detected in the more than 22 million orthogonal transfer CCD images obtained as part of the Pan-STARRS1 $3\pi$ survey. Over 85 billion instances of those objects have been automatically detected…

Large sets of objects with spectroscopic redshift measurements will be needed for imaging dark energy experiments to achieve their full potential, serving two goals:_training_, i.e., the use of objects with known redshift to develop and…

We present a new algorithm to estimate quasar photometric redshifts (photo-$z$s), by considering the asymmetries in the relative flux distributions of quasars. The relative flux models are built with multivariate Skew-t distributions in the…

We present and describe a catalog of galaxy photometric redshifts (photo-z's) for the Sloan Digital Sky Survey (SDSS) Coadd Data. We use the Artificial Neural Network (ANN) technique to calculate photo-z's and the Nearest Neighbor Error…

As a contribution to the understanding of the dark energy concept, the Dark energy American French Team (DAFT, in French FADA) has started a large project to characterize statistically high redshift galaxy clusters, infer cosmological…

A precise measurement of photometric redshifts (photo-z) is key for the success of modern photometric galaxy surveys. Machine learning (ML) methods show great promise in this context, but suffer from covariate shift (CS) in training sets…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-19 Chiara Moretti , Maximilian Autenrieth , Riccardo Serra , Roberto Trotta , David A. van Dyk , Andrei Mesinger

We demonstrate that the design of the Sloan Digital Sky Survey (SDSS) filter system and the quality of the SDSS imaging data are sufficient for determining accurate and precise photometric redshifts (``photo-z''s) of quasars. Using a sample…

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

We introduce Z-Sequence, a novel empirical model that utilises photometric measurements of observed galaxies within a specified search radius to estimate the photometric redshift of galaxy clusters. Z-Sequence itself is composed of a…

Astrophysics of Galaxies · Physics 2021-04-26 Matthew C. Chan , John P. Stott

Wide-area imaging surveys are one of the key ways of advancing our understanding of cosmology, galaxy formation physics, and the large-scale structure of the Universe in the coming years. These surveys typically require calculating…

Astrophysics of Galaxies · Physics 2020-10-07 P. W. Hatfield , I. A. Almosallam , M. J. Jarvis , N. Adams , R. A. A. Bowler , Z. Gomes , S. J. Roberts , C. Schreiber

We present an enhanced version of the multiwavelength spectral modeling code MAGPHYS that allows the estimation of galaxy photometric redshift and physical properties (e.g., stellar mass, star formation rate, dust attenuation)…

Astrophysics of Galaxies · Physics 2019-09-11 A. J. Battisti , E. da Cunha , K. Grasha , M. Salvato , E. Daddi , L. Davies , S. Jin , D. Liu , E. Schinnerer , M. Vaccari

Astronomy has entered the big data era and Machine Learning based methods have found widespread use in a large variety of astronomical applications. This is demonstrated by the recent huge increase in the number of publications making use…

Instrumentation and Methods for Astrophysics · Physics 2018-07-17 Massimo Brescia , Stefano Cavuoti , Valeria Amaro , Giuseppe Riccio , Giuseppe Angora , Civita Vellucci , Giuseppe Longo

We simulate the performance of a new type of instrument, a Superconducting Multi-Object Spectrograph (SuperMOS), that uses Microwave Kinetic Inductance Detectors (MKIDs). MKIDs, a new detector technology, feature good QE in the UVOIR, can…

Instrumentation and Methods for Astrophysics · Physics 2015-06-16 Danica Marsden , Benjamin A. Mazin , Kieran O'Brien , Chris Hirata

Having a need to perform differential photometry for tens of thousands stars in a several square degrees field, we developed Astrokit program. The software corrects the star brightness variations caused by variations of atmospheric…

Instrumentation and Methods for Astrophysics · Physics 2015-06-22 Artem Y. Burdanov , Vadim V. Krushinsky , Alexander A. Popov

Due to the necessity to evaluate photo-z for a variety of huge sky survey data sets, it seemed important to provide the astronomical community with an instrument able to fill this gap. Besides the problem of moving massive data sets over…

Instrumentation and Methods for Astrophysics · Physics 2016-02-18 Stefano Cavuoti , Massimo Brescia , Virgilio De Stefano , Giuseppe Longo
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