中文
相关论文

相关论文: Abundance sensitive points of line profiles in the…

200 篇论文

Understanding the evolution of the Milky Way calls for the precise abundance determination of many elements in many stars. A common perception is that deriving more than a few elemental abundances ([Fe/H], [$\alpha$/Fe], perhaps [C/H],…

太阳与恒星天体物理 · 物理学 2017-07-05 Yuan-Sen Ting , Charlie Conroy , Hans-Walter Rix , Phillip Cargile

The derivation of nebular abundances in galaxies using strong line methods is simple and quick. Various indices have been designed and calibrated for this purpose, and they are widely used. However, abundances derived with such methods may…

宇宙学与河外天体物理 · 物理学 2015-05-14 Grazyna Stasinska

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.…

天体物理学 · 物理学 2007-05-23 C. Allende Prieto

We propose a new method for determination of element abundances in stellar atmospheres aimed for the automatic processing of high-quality stellar spectra. The pan-spectral method is based on weighted cumulative line-widths Q of studied…

天体物理学 · 物理学 2012-04-02 A. Sapar , A. Aret , L. Sapar , R. Poolamäe

*Context: The optimisation of new multiplex spectrographs (resolution, wavelength range,...), their associated surveys (choice of setup), or their parameterisation pipelines require methods that estimate which wavelengths contain useful…

天体物理仪器与方法 · 物理学 2023-06-14 Georges Kordopatis , Vanessa Hill , Karin Lind

FUSE spectra of star-forming regions in nearby galaxies are compared to composite spectra of Lyman-break galaxies (LBGs), binned by strength of Lyman alpha emission and by mid-UV luminosity. Several far-UV spectral features, including lines…

天体物理学 · 物理学 2008-11-26 William C. Keel

To analyse stellar populations in galaxies a widely used method is to apply theoretically derived responses of stellar spectra and line indices to element abundance variations, hereafter referred to as response functions. These are applied…

太阳与恒星天体物理 · 物理学 2015-06-16 A. E. Sansom , A. de Castro Milone , A. Vazdekis , P. Sanchez-Blazquez

Stellar emission and absorption lines are routinely observed in galaxies at redshifts up to 5 with spectrographs on 8-10m class telescopes. While the overall spectra are well understood and have been successfully modeled using empirical and…

太阳与恒星天体物理 · 物理学 2013-12-10 Claus Leitherer

A number of large spectroscopic surveys of stars in the Milky Way are under way or are being planned. In this context it is important to discuss the extent to which elemental abundances can be used as discriminators between different (known…

星系天体物理 · 物理学 2015-06-15 Lennart Lindegren , Sofia Feltzing

We have used a combination of stellar population synthesis and photoionization models to develop a set of ionization parameter and abundance diagnostics based only on the use of the strong optical emission lines. These models are applicable…

天体物理学 · 物理学 2008-11-26 L. J. Kewley , M. A. Dopita

An ever-looming threat to astronomical applications of machine learning is the danger of over-fitting data, also known as the `curse of dimensionality.' This occurs when there are fewer samples than the number of independent variables. In…

天体物理仪器与方法 · 物理学 2023-12-29 Sankalp Gilda

Methods to determine abundances of the elements in the atmospheres of F, G, and K stars with precisions of 0.01-0.03 dex are reviewed. Such high-precision stellar abundances have led to the discovery of unexpected phenomena and relations…

太阳与恒星天体物理 · 物理学 2018-11-06 Poul Erik Nissen , Bengt Gustafsson

Over the last half-century quantitative stellar spectroscopy has made great progress. However, most stellar abundance analyses today still employ rather simplified models, which can introduce severe systematic errors swamping the…

天体物理学 · 物理学 2007-05-23 Martin Asplund

Weak lensing convergence can be used directly to map and probe the dark mass distribution in the universe. Building on earlier studies, we recall how the statistics of the convergence field are related to the statistics of the underlying…

天体物理学 · 物理学 2009-11-07 Andrew J. Barber , Dipak Munshi , Patrick Valageas

We present a compilation of spectral energy distributions of 35 weak AGNs in LINERs using recent data from the published literature. We make use of previously published compilations of data, after complementing and extending them with more…

星系天体物理 · 物理学 2015-05-18 Michael Eracleous , Jason A. Hwang , Helene M. L. G. Flohic

(abriged) Stellar clusters with the same general physical properties (e.g., total mass, age, and star-formation mode) may have very different stellar mass spectra due to the incomplete sampling of the underlying mass function; such…

天体物理学 · 物理学 2009-11-07 M. Cervino , V. Luridiana , E. Perez , J. M. Vilchez , D. Valls-Gabaud

We approach the following question: if supersymmetry is discovered, how can we select among different supersymmetric extensions of the Standard Model? In particular, we perform an analysis of the sparticle spectrum in low-energy string…

高能物理 - 唯象学 · 物理学 2009-11-07 B. C. Allanach , D. Grellscheid , F. Quevedo

Many recent studies have demonstrated that scaling arguments, such as the so-called hierarchical {\em ansatz}, are extremely useful in understanding the statistical properties of weak gravitational lensing. This is especially true on small…

天体物理学 · 物理学 2009-10-31 Dipak Munshi , Peter Coles

Stellar spectra derived from current multiple-object fiber-fed spectroscopic radial-velocity surveys, of the type feasible with, among other examples, AUTOFIB, 2dF, HYDRA, NESSIE, and the Sloan survey, differ significantly from those…

天体物理学 · 物理学 2007-05-23 J. Bryn Jones , Rosemary F. G. Wyse , Gerard Gilmore

CONTEXT: Spectral-line asymmetries and wavelength shifts are signatures of hydrodynamics in solar and stellar atmospheres. Theory may precisely predict idealized lines, but observed spectra are limited by blends, too few suitable lines,…

天体物理学 · 物理学 2009-11-13 Dainis Dravins
‹ 上一页 1 2 3 10 下一页 ›