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Related papers: Spectral Analysis in the Virtual Observatory

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Singular Spectrum Analysis (SSA) or Singular Value Decomposition (SVD) are often used to de-noise univariate time series or to study their spectral profile. Both techniques rely on the eigendecomposition of the cor- relation matrix…

Signal Processing · Electrical Eng. & Systems 2018-07-30 A. M. Tomé , D. Malafaia , A. R. Teixeira , E. W. Lang

We present the general purpose spectral energy distribution (SED) fitting tool SED Analysis Through Markov Chains (SATMC). Utilizing Monte Carlo Markov Chain (MCMC) algorithms, SATMC fits an observed SED to SED templates or models of the…

Instrumentation and Methods for Astrophysics · Physics 2013-09-19 S. P. Johnson , G. W. Wilson , Y. Tang , K. S. Scott

The U.S. Virtual Astronomical Observatory was a software infrastructure and development project designed both to begin the establishment of an operational Virtual Observatory (VO) and to provide the U.S. coordination with the international…

Instrumentation and Methods for Astrophysics · Physics 2015-04-10 R. J. Hanisch , G. B. Berriman , T. J. W. Lazio , S. Emery Bunn , J. Evans , T. A. McGlynn , R. Plante

Context. As increasingly more spectroscopic data are being delivered by medium- and high-resolving power multi-object spectrographs, more automatic stellar parameter determination softwares are being developed. The quality of the spectra…

Solar and Stellar Astrophysics · Physics 2012-09-04 Helene Posbic , David Katz , Elisabetta Caffau , Piercarlo Bonifacio , Ana Gomez , Luca Sbordone , Frederic Arenou

The current detectors of gamma-ray emission specially at TeV energies have too poor resolution to determine whether this emission is produced in the jet or in the core, particularly of low luminous, non-blazar AGNs (like radio galaxies). In…

High Energy Astrophysical Phenomena · Physics 2016-10-28 Behrouz Khiali , Elisabete M. de Gouveia Dal Pino , Hélène Sol

A grid of ATLAS9 model atmospheres has been computed, spanning 3500 K <= T_eff <= 8000 K, 0.0 <= log g <= 5.0, -4.0 <= [M/H] <= 0.0, and -0.8 < [alpha/Fe] <= +1.2. These parameters are appropriate for stars in the red giant branch, subgiant…

Solar and Stellar Astrophysics · Physics 2011-10-26 Evan N. Kirby

The spectral energy distribution (SED) of observed stars in wide-field images is crucial for chromatic point spread function (PSF) modelling methods, which use unresolved stars as integrated spectral samples of the PSF across the field of…

Instrumentation and Methods for Astrophysics · Physics 2025-02-19 Ezequiel Centofanti , Samuel Farrens , Jean-Luc Starck , Tobias Liaudat , Alex Szapiro , Jennifer Pollack

The next generation of High Energy Physics (HEP) experiments requires a GRID approach to a distributed computing system and the associated data management: the key concept is the Virtual Organisation (VO), a group of distributed users with…

The mass-loss rates from single massive stars are high enough to form radio photospheres at large distances from the stellar surface where the wind is optically thick to (thermal) free-free opacity. Here we calculate the far-infrared,…

Solar and Stellar Astrophysics · Physics 2022-06-15 Christiana Erba , Richard Ignace

How to analyse Terabytes of photometric data, and extract knowledge on variable stars? How to detect variable phenomena? How to combine different photometric bands? Which algorithm to search for periods? How to characterize and classify the…

Astrophysics · Physics 2007-05-23 Laurent Eyer

In this contribution we report the current stage of the MOLecular Dissociation (MOL-D) database which is a web service within the Serbian virtual observatory (SerVO) and node within Virtual Atomic and Molecular Data Center (VAMDC). MOL-D is…

Instrumentation and Methods for Astrophysics · Physics 2017-06-20 Vladimir A. Sreckovic , Darko Jevremovic , Veljko Vujcic , Ljubinko M. Ignjatovic , Nenad Milovanovic , Sanja Erkapic , Milan S. Dimitrijevic

As private space companies such as SpaceX and Telesat are building large LEO satellite constellations to provide global broadband Internet access, researchers have proposed to embed compute services within satellite constellations to…

Distributed, Parallel, and Cluster Computing · Computer Science 2022-04-15 Tobias Pfandzelter , David Bermbach

Our multi-wavelength model GRASIL for the SED of galaxies is described, in particular the recent extension to the radio and X-ray range. With our model we can study different aspects of galaxy evolution by exploiting all available spectral…

Astrophysics · Physics 2016-01-27 L. Silva , G. L. Granato , A. Bressan , P. Panuzzo

We present the GalMer database, a library of galaxy merger simulations, made available to users through tools compatible with the Virtual Observatory (VO) standards adapted specially for this theoretical database. To investigate the physics…

Instrumentation and Methods for Astrophysics · Physics 2015-05-18 Igor Chilingarian , Paola Di Matteo , Francoise Combes , Anne-Laure Melchior , Benoit Semelin

Accurate acquisition of surface meteorological conditions at arbitrary locations holds significant importance for weather forecasting and climate simulation. Due to the fact that meteorological states derived from satellite observations are…

Machine Learning · Computer Science 2025-02-13 Siwei Tu , Ben Fei , Weidong Yang , Fenghua Ling , Hao Chen , Zili Liu , Kun Chen , Hang Fan , Wanli Ouyang , Lei Bai

We present a visibility based estimator namely, the Tapered Gridded Estimator (TGE) to estimate the power spectrum of the diffuse sky signal. The TGE has three novel features. First, the estimator uses gridded visibilities to estimate the…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-16 Samir Choudhuri

Leveraging the photometric data of the Sloan Digital Sky Survey and the Galaxy Evolution Explorer (GALEX), we construct mean/median spectral energy distributions (SEDs) for unique bright quasars in redshift bins of 0.2 and up to $z \simeq…

Astrophysics of Galaxies · Physics 2024-11-21 Zhen-Yi Cai

To address the lack of public power system data for machine learning research in energy networks, we investigate the use of variational graph autoencoders (VGAEs) for synthetic distribution grid generation. Using two open-source datasets,…

Machine Learning · Computer Science 2025-12-02 Syed Zain Abbas , Ehimare Okoyomon

Spectral energy distributions are computed using 2D rotating stellar models and NLTE plane parallel model atmospheres. A rotating, 2D stellar model has been found which matches the observed ultraviolet and visible spectrum of ? Oph. The SED…

Solar and Stellar Astrophysics · Physics 2015-06-04 Robert G. Deupree , Diego Castañeda , Fernando Peña , C. Ian Short

Multi-wavelength observations with TeV photons are an essential diagnostic tool to study the physics of TeV sources. The complex variability of blazars, however (timescales from years down to minutes, with different patterns and SED…

Astrophysics · Physics 2009-11-10 L. Costamante
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