English
Related papers

Related papers: Advanced Data Analysis for Observational Cosmology…

200 papers

We present an analysis of the submillimetre/X-ray properties of 19 X-ray absorbed, Compton-thin quasi-stellar objects (QSOs) selected to have luminosities and redshifts which represent the peak of cosmic QSO activity. i.e. ~L* objects at…

Background In analytical chemistry, spatial information about materials is commonly captured through imaging techniques, such as traditional color cameras or with advanced hyperspectral cameras and microscopes. However, efficiently…

Computer Vision and Pattern Recognition · Computer Science 2025-11-07 Puneet Mishra , Martijntje Vollebregt , Yizhou Ma , Maria Font-i-Furnols

A statistical analysis of the space-time distribution of absorption-line systems (ALSs) observed in QSO spectra within the cosmological redshift interval $z$=0.0--3.7 is carried out on the base of our catalog of absorption systems…

Astrophysics · Physics 2008-11-26 A. I. Ryabinkov , A. D. Kaminker , D. A. Varshalovich

We present a data-driven technique to analyze multifrequency images from upcoming cosmological surveys mapping large sky area. Using full information from the data at the two-point level, our method can simultaneously constrain the…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-01 Yun-Ting Cheng , Benjamin D. Wandelt , Tzu-Ching Chang , Olivier Dore

This review summarizes popular unsupervised learning methods, and gives an overview of their past, current, and future uses in astronomy. Unsupervised learning aims to organise the information content of a dataset, in such a way that…

Instrumentation and Methods for Astrophysics · Physics 2024-06-26 Sotiria Fotopoulou

We discuss the detectability of Warm/Hot Intergalactic medium (WHIM) via the absorption lines toward bright point sources with a future X-ray satellite mission, XEUS. While we consider bright QSOs as specific examples, the methodology can…

The recently unveiled deep-field images from the James Webb Space Telescope have renewed interest in what we can and cannot see of the universe. Answering these questions requires understanding the so-called "cosmological horizons" and the…

General Relativity and Quantum Cosmology · Physics 2025-07-15 Michele Re Fiorentin , Stefano Re Fiorentin

The complexity and accuracy of current and future precision cosmology observational campaigns has made it essential to develop an efficient technique for directly combining simulation and observational datasets to determine cosmological and…

Astrophysics · Physics 2009-11-11 Katrin Heitmann , David Higdon , Charles Nakhleh , Salman Habib

Gaussian processes provide a method for extracting cosmological information from observations without assuming a cosmological model. We carry out cosmography -- mapping the time evolution of the cosmic expansion -- in a model-independent…

Cosmology and Nongalactic Astrophysics · Physics 2012-07-11 Arman Shafieloo , Alex G. Kim , Eric V. Linder

Using visible, radio, microwave, and sub-mm data, we study several lines of sight toward stars generally closer than 1 kpc on a component-by-component basis. We derive the component structure seen in absorption at visible wavelengths from…

Broad Absorption Line Quasars (BALQSOs) displaying distinct blue-shifted broad absorption lines. These serve as invaluable probes for unraveling the intricate structure and evolution of quasars, shedding light on the profound influence…

Astrophysics of Galaxies · Physics 2024-06-04 Wei-Bo Kao , Yanxia Zhang , Xue-Bing Wu

Fundamental information about the Universe is encoded in anisotropies of the Cosmic Microwave Background (CMB) radiation. To make full use of this information, an experiment must image the entire sky with the angular resolution,…

The understanding of the nature of ultra-high-energy cosmic rays is one of the most intriguing open questions for current and future observatories. These particles are expected to be accelerated in extragalactic sources. Because of their…

High Energy Astrophysical Phenomena · Physics 2016-12-28 Mariangela Settimo

The analysis of the submm anisotropies that will be mapped by the forthcoming MAP and PLANCK satellites requires careful foreground subtraction before measuring CMB fluctuations. Among these, the foreground due to IR/submm thermal radiation…

Astrophysics · Physics 2007-05-23 B. Guiderdoni

Object perception is a fundamental sub-field of Computer Vision, covering a multitude of individual areas and having contributed high-impact results. While Machine Learning has been traditionally applied to address related problems, recent…

Computer Vision and Pattern Recognition · Computer Science 2020-03-18 Filippos Gouidis , Alexandros Vassiliades , Theodore Patkos , Antonis Argyros , Nick Bassiliades , Dimitris Plexousakis

The tightest cosmological constraints currently available are obtained by combining complementary data sets. When combining correlated data sets, various astrophysical biases that affect the measurements must be identified and treated.…

Cosmology and Nongalactic Astrophysics · Physics 2022-12-15 Yuuki Omori

In the past years modern mathematical methods for image analysis have led to a revolution in many fields, from computer vision to scientific imaging. However, some recently developed image processing techniques successfully exploited by…

Instrumentation and Methods for Astrophysics · Physics 2015-01-19 Marco Castellano , Daniele Ottaviani , Adriano Fontana , Emiliano Merlin , Stefano Pilo , Maurizio Falcone

Cosmography is the tool that makes possible to untie the interpretation of cosmological observations from the definition of any dynamical prior. We review the constraints on the cosmographic parameter obtained using the most thorough data…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-01 Vincenzo Vitagliano , Jun-Qing Xia , Stefano Liberati , Matteo Viel

In the central regions of active galaxies, dense molecular medium are exposed to various types of radiation and energy injections, such as UV, X-ray, cosmic ray, and shock dissipation. With the rapid progress of chemical models and…

Astrophysics of Galaxies · Physics 2017-01-11 Kotaro Kohno , Ryo Ando , Akio Taniguchi , Takuma Izumi , Tomoka Tosaki

Every field of Science is undergoing unprecedented changes in the discovery process, and Astronomy has been a main player in this transition since the beginning. The ongoing and future large and complex multi-messenger sky surveys impose a…

Instrumentation and Methods for Astrophysics · Physics 2021-05-12 Maurizio D'Addona , Giuseppe Riccio , Stefano Cavuoti , Crescenzo Tortora , Massimo Brescia