English
Related papers

Related papers: Automatic line selection for abundance determinati…

200 papers

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

Context. High-resolution spectroscopy in the near-infrared (NIR) is a powerful tool for characterising the physical and chemical properties of cool-star atmospheres. The current generation of NIR echelle spectrographs enables the sampling…

Solar and Stellar Astrophysics · Physics 2021-01-04 C. Fanelli , L. Origlia , E. Oliva , A. Mucciarelli , N. Sanna , E. Dalessandro , D. Romano

Innovation in the ground and space-based instruments has taken us into a new age of spectroscopy, in which a large amount of stellar content is becoming available. So, automatic classification of stellar spectra became subjective in recent…

Solar and Stellar Astrophysics · Physics 2020-06-26 Y. A. Azzam , M. I. Nouh , A. A. Shaker

We have derived elemental abundances of three field red horizontal branch stars using high-resolution (R$\simeq$ 45,000), high signal-to-noise ratio (S/N $\gtrsim$ 200) $H$ and $K$ band spectra obtained with the Immersion Grating Infrared…

Automatic discovery and curve fitting of absorption bands in hyperspectral data can enable the analyst to identify materials present in a scene by comparison with library spectra. This procedure is common in laboratory spectra, but is…

Instrumentation and Methods for Astrophysics · Physics 2014-01-23 Adrian J. Brown

We provide a new method to derive heavy element abundances based on the unique suite of nebular lines in the mid- to far-infrared (IR) range. Using grids of photo-ionisation models that cover a wide range in O/H and N/O abundances, and…

Astrophysics of Galaxies · Physics 2021-08-11 J. A. Fernández-Ontiveros , E. Pérez-Montero , J. M. Vílchez , R. Amorín , L. Spinoglio

Active galactic nuclei (AGN) are typically identified through their distinctive X-ray or radio emissions, mid-infrared (MIR) colors, or emission lines. However, each method captures different subsets of AGN due to signal-to-noise (SNR)…

A spectroscopic analysis of stellar spectra can be carried out using different approaches; different methods, line lists, atomic parameters, solar abundances etc. The resulting atmospheric parameters from these choices can vary beyond…

Solar and Stellar Astrophysics · Physics 2019-02-13 Ditte Slumstrup , Frank Grundahl , Victor Silva Aguirre , Karsten Brogaard

Recently, sparsity-based algorithms are proposed for super-resolution spectrum estimation. However, to achieve adequately high resolution in real-world signal analysis, the dictionary atoms have to be close to each other in frequency,…

Machine Learning · Statistics 2015-06-05 Yiyuan She , Huanghuang Li , Jiangping Wang , Dapeng Wu

We have developed techniques to extract true iron abundances and surface gravities from spectra of the type provided by the multiple-object fibre-fed spectroscopic radial-velocity surveys underway with 2dF, HYDRA, NESSIE, and the…

Astrophysics · Physics 2007-05-23 J. Bryn Jones , Gerard Gilmore , Rosemary F. G. Wyse

Photospheric parameters and abundances are presented for a sample of single-lined chromospherically active binaries from a differential LTE analysis of high-resolution spectra. Abundances have been derived for 13 chemical species, including…

Astrophysics · Physics 2009-11-10 T. Morel , G. Micela , F. Favata , D. Katz , I. Pillitteri

With the large amounts of spectroscopic data available today and the very large surveys to come (e.g. Gaia), the need for automatic data analysis software is unquestionable. We thus developed an automatic spectra analysis program for the…

Astrophysics of Galaxies · Physics 2015-06-03 Helene Posbic , David Katz , Elisabetta Caffau , Piercarlo Bonifacio , Luca Sbordone , Ana Gomez , Frederic Arenou

A fundamental challenge for wide-field imaging surveys is obtaining follow-up spectroscopic observations: there are > $10^9$ photometrically cataloged sources, yet modern spectroscopic surveys are limited to ~few x $10^6$ targets. As we…

Solar and Stellar Astrophysics · Physics 2015-06-23 A. A. Miller , J. S. Bloom , J. W. Richards , Y. S. Lee , D. L. Starr , N. R. Butler , S. Tokarz , N. Smith , J. A. Eisner

Opacities of molecules in exoplanet atmospheres rely on increasingly detailed line-lists for these molecules. The line lists available today contain for many species up to several billions of lines. Computation of the spectral line profile…

Earth and Planetary Astrophysics · Physics 2017-11-08 Michiel Min

We are able to clearly distinguish the processes responsible for enhanced low-intensity atomic Kerr nonlinearity, namely coherent population trapping and coherent population oscillations in experiments performed on the Rb D1 line, where one…

Atomic Physics · Physics 2015-06-05 A. M. Akulshin , R. J. McLean

Context. This work is part of a long-term spectroscopic study of a sample of 30 multiple stars with early-type components. In this second paper we present the results of six multiple systems in which new stellar components have been…

Solar and Stellar Astrophysics · Physics 2014-09-05 M. E. Veramendi , J. F. González

Characterizing exoplanet host stars at a population level requires a method of homogeneously characterizing stellar properties across all spectral types. To this end, we have developed Metal Pipe, a new code for determining stellar…

Solar and Stellar Astrophysics · Physics 2026-01-19 Jared R. Kolecki , Lauren M. Weiss

There has been an incredibly large investment in obtaining high-resolution stellar spectra for determining chemical abundances of stars. This information is crucial to answer fundamental questions in Astronomy by constraining the formation…

Solar and Stellar Astrophysics · Physics 2019-09-11 Paula Jofré , Ulrike Heiter , Caroline Soubiran

Mass spectrometry provides a high-throughput approach to identify proteins in biological samples. A key step in the analysis of mass spectrometry data is to identify the peptide sequence that, most probably, gave rise to each observed…

Applications · Statistics 2013-01-14 Qunhua Li , Jimmy K. Eng , Matthew Stephens

The identification of spectral lines can be a tedious process requiring the interrogation of large spectroscopic databases, but it does lend itself to software algorithms that can determine the characteristics of candidate line…

Astrophysics · Physics 2009-11-10 Brian Sharpee , Robert Williams , Jack A. Baldwin , Peter A. M. van Hoof
‹ Prev 1 4 5 6 7 8 10 Next ›