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Related papers: Advances in Spectral Classification

200 papers

The determination of chemical composition is crucial for investigating the formation and evolution of star forming galaxies and provides a powerful tool to constrain the effects of galactic winds and accretion from the cosmic web. In this…

Astrophysics of Galaxies · Physics 2018-10-03 Rolf Kudritzki , Miguel A. Urbaneja

The growth of sky surveys and the large amount of stellar spectra in the current databases, has generated the necessity of developing new methods to estimate atmospheric parameters, a fundamental task on stellar research. In this work we…

Instrumentation and Methods for Astrophysics · Physics 2022-06-27 Miguel Flores R. , Luis J. Corral , Celia R. Fierro-Santillán

In the last two decades about a dozen methods were invented which derive, from a series of composite spectra over the orbit, the spectra of individual components in binary and multiple systems. Reconstructed spectra can then be analyzed…

Solar and Stellar Astrophysics · Physics 2009-09-18 K. Pavlovski , H. Hensberge

Context. The Spectroscopy Made Easy (SME) package has become a popular tool for analyzing stellar spectra, often in connection with large surveys or exoplanet research. SME has evolved significantly since it was first described in 1996, but…

Instrumentation and Methods for Astrophysics · Physics 2016-12-21 Nikolai Piskunov , Jeff A. Valenti

The Square Kilometer Array will have the sensitivity, spatial resolution, and frequency resolution to provide new scientific knowledge of evolved stars. Four basic areas of scientific exploration are enhanced by the construction of the SKA:…

Astrophysics · Physics 2009-11-10 Kevin Marvel

We review recent developments in determining the evolution of magnetic massive OB stars. One of the important scientific questions is the completeness and the detection limits of contemporaneous spectropolarimetric surveys across the HR…

Solar and Stellar Astrophysics · Physics 2020-04-10 Veronique Petit , Alexandre David-Uraz

We describe a technique for deriving effective temperatures, surface gravities, rotation velocities, and radial velocities from high resolution near-IR spectra. The technique matches the observed near-IR spectra to spectra synthesized from…

Astrophysics · Physics 2009-11-10 G. W. Doppmann , D. T. Jaffe

The determination of chemical abundances from stellar spectra is considered a mature field of astrophysics. Digital spectra of stars are recorded and processed with standard techniques, much like samples in the biological sciences.…

Astrophysics · Physics 2007-05-23 C. Allende Prieto

Stellar spectral classification has been highly useful in the study of stars. While there is a currently accepted spectral classification system for carbon stars, the subset of Hydrogen-deficient Carbon (HdC) stars has not been well…

Stellar model atmospheres form the basis for any element abundance determination and hence are crucial ingredients for studies of stellar, galactic and cosmic evolution. With recent observational progress with the advent of 8m-class…

Astrophysics · Physics 2007-05-23 Martin Asplund

Despite their paucity, massive hot stars are real cosmic engines of fundamental importance in shaping our Universe, from its very early stages up to its current appearance. Understanding the physics of massive stars is then a key issue for…

Astrophysics · Physics 2007-08-22 Miguel A. Urbaneja , Rolf Peter Kudritzki , Fabio Bresolin

We review the recent discoveries of magnetic fields in different types of massive stars and briefly discuss strategies for spectropolarimetric observations to be carried out in the future.

The notions of spectral measures and spectral classes, which are well known for graphs, are generalized and investigated for oriented hypergraphs.

Combinatorics · Mathematics 2021-02-16 Raffaella Mulas

In recent years, deep learning techniques revolutionized the way remote sensing data are processed. Classification of hyperspectral data is no exception to the rule, but has intrinsic specificities which make application of deep learning…

Machine Learning · Computer Science 2019-04-25 Nicolas Audebert , Bertrand Saux , Sébastien Lefèvre

Asteroseismology and spectropolarimetry have allowed us to progress significantly in our understanding of the physics of hot stars over the last decade. It is now possible to combine these two techniques to learn even more information about…

Solar and Stellar Astrophysics · Physics 2015-06-22 Coralie Neiner , Maryline Briquet , Stéphane Mathis , Pieter Degroote

Hyperspectroscopy is a new method of surface image taking, providing simultaneously high position and spectral resolutions which allow one to make some conclusions about chemical compositions of the surfaces. We are now studying…

Instrumentation and Detectors · Physics 2016-11-18 I. Rodionov , J-M. Bidault , I. Crotty , P. Fonte , F. Galy , V. Peskov , O. Zanette

We describe the spectral classification of white dwarfs and some of the physical processes important for their understanding. In the major part of this paper we discuss the input physics and computational methods for one of the most widely…

Astrophysics · Physics 2008-12-03 Detlev Koester

Achieving high accuracy and precision in stellar parameter and chemical composition determinations is challenging in massive star spectroscopy. On one hand, the target selection for an unbiased sample build-up is complicated by several…

Solar and Stellar Astrophysics · Physics 2017-11-15 Maria-Fernanda Nieva , Norbert Przybilla

A new method for classification of galaxy spectra is presented, based on a recently introduced information theoretical principle, the `Information Bottleneck'. For any desired number of classes, galaxies are classified such that the…

Astrophysics · Physics 2009-10-31 N. Slonim , R. Somerville , N. Tishby , O. Lahav

I present an overview of the science goals and achievements of ongoing spectroscopic surveys of individual stars in the nearby Universe. I include a brief discussion of the development of the field of Galactic Archaeology - using the fossil…

Astrophysics of Galaxies · Physics 2016-04-19 Rosemary F. G. Wyse