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Related papers: A Unified Framework for Photometric Redshifts

200 papers

The next generation of weak gravitational lensing surveys is capable of generating good measurements of cosmological parameters, provided that, amongst other requirements, adequate redshift information is available for the background…

Astrophysics · Physics 2009-11-11 Edward Edmondson , Lance Miller , Christian Wolf

We survey some of our recent results on inverse problems for evolution equations. The goal is to provide a unified approach to solve various types of evolution equations. The inverse problems we consider consist in determining unknown…

Analysis of PDEs · Mathematics 2019-12-09 Kaïs Ammari , Mourad Choulli , Faouzi Triki

Many of the cosmological tests to be performed by planned dark energy experiments will require extremely well-characterized photometric redshift measurements. Current estimates are that the true mean redshift of the objects in each photo-z…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-22 Daniel J. Matthews , Jeffrey A. Newman

Studies of the distribution and evolution of galaxies are of fundamental importance to modern cosmology; these studies, however, are hampered by the complexity of the competing effects of spectral and density evolution. Constructing a…

Astrophysics · Physics 2009-10-31 R. J. Brunner , A. J. Connolly , A. S. Szalay

Photometric redshift estimation algorithms are often based on representative data from observational campaigns. Data-driven methods of this type are subject to a number of potential deficiencies, such as sample bias and incompleteness.…

Cosmology and Nongalactic Astrophysics · Physics 2022-07-06 Nesar Ramachandra , Jonás Chaves-Montero , Alex Alarcon , Arindam Fadikar , Salman Habib , Katrin Heitmann

The availability of large, public, multi-modal astronomical datasets presents an opportunity to execute novel research that straddles the line between science of AI and science of astronomy. Photometric redshift estimation is a…

Instrumentation and Methods for Astrophysics · Physics 2024-02-07 Andrew Engel , Gautham Narayan , Nell Byler

To produce images that are suitable for display, tone-mapping is widely used in digital cameras to map linear color measurements into narrow gamuts with limited dynamic range. This introduces non-linear distortion that must be undone,…

Computer Vision and Pattern Recognition · Computer Science 2014-11-11 Ayan Chakrabarti , Ying Xiong , Baochen Sun , Trevor Darrell , Daniel Scharstein , Todd Zickler , Kate Saenko

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

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

We describe and experimentally validate an algorithm to reconstruct an unknown extended object from through-focus measured image intensities blurred by unknown aberrations. It is shown that the method can recover diffraction-limited image…

Optics · Physics 2015-10-29 Yifeng Shao , Niek Doelman , Silvania F. Pereira , H. Paul Urbach

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

Inverse ellipsometry, i.e., reconstructing optical constants and film thickness from the measured phase difference $\Delta$ and amplitude ratio $\Psi$, is a fundamentally ill-posed problem. Traditional solutions rely on slow, expert-driven…

Machine Learning · Computer Science 2026-03-20 Yiming Ma , Jianzhi Teng , Xinjie Li , Xin Sun , Zhiyong Wang , Yuzhou Song , Lionel Z. Wang , Bin Chen

This article adapts the framework of metamorphosis to solve inverse problems in imaging that includes joint reconstruction and image registration. The deformations in question have two components, one that is a geometric deformation moving…

Computer Vision and Pattern Recognition · Computer Science 2018-06-25 Gris Barbara , Chen Chong , Öktem Ozan

We introduce a framework for uncertainty estimation that both describes and extends many existing methods. We consider typical hyperparameters involved in classical training as random variables and marginalise them out to capture various…

Machine Learning · Computer Science 2021-07-07 Francesco Farina , Lawrence Phillips , Nicola J Richmond

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

We propose a new technique for estimating spatially varying parametric materials from a single image of an object with unknown shape in unknown illumination. Our method uses a low-order parametric reflectance model, and incorporates strong…

Graphics · Computer Science 2019-12-30 Kevin Karsch , David Forsyth

Machine learning methods for computational imaging require uncertainty estimation to be reliable in real settings. While Bayesian models offer a computationally tractable way of recovering uncertainty, they need large data volumes to be…

Machine Learning · Computer Science 2020-08-24 Francesco Tonolini , Jack Radford , Alex Turpin , Daniele Faccio , Roderick Murray-Smith

Waveform inversion is theoretically a powerful tool to reconstruct subsurface structures, but a usually encountered problem is that accurate sources are very rare, causing the computation unstable and divergent. This challenging problem,…

Geophysics · Physics 2024-07-12 Han Yu

We propose a paradigm shift in the data-driven modeling of the instrumental response field of telescopes. By adding a differentiable optical forward model into the modeling framework, we change the data-driven modeling space from the pixels…

Instrumentation and Methods for Astrophysics · Physics 2021-12-16 Tobias Liaudat , Jean-Luc Starck , Martin Kilbinger , Pierre-Antoine Frugier
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