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Recently it is advocated that high intensity and low energy $(E_\nu \sim 2 GeV)$ neutrino beams should be built to probe the $(13)$ mixing angle $\phi$ to a level of a few parts in $10^4$. Experiments using such beams will have better…

高能物理 - 唯象学 · 物理学 2009-10-31 Mohan Narayan , S. Uma Sankar

A collection of the best solar and laboratory spectra in the soft X-rays is used here to perform a preliminary benchmark in this wavelength region, by comparing observed vs. predicted wavelengths and calibrated solar irradiances. The…

太阳与恒星天体物理 · 物理学 2015-06-11 G. Del Zanna

We list vacuum wavelengths, energy levels, statistical weights, transition probabilities and oscillator strengths for permitted resonance spectral lines of all ions of 18 astrophysically important elements (H through Si, S, Ar, Ca, Fe).…

atom-ph · 物理学 2009-10-28 D. A. Verner , E. M. Verner , G. J. Ferland

We present the results of a detailed theoretical study which meets the spatial and temporal criteria of the Debye-Hu\"ckel (DH) approximation on the variation of the transition energies as well as the oscillator strengths for the ${2p^53d\…

原子物理 · 物理学 2019-11-20 Chensheng Wu , Shaomin Chen , T. N. Chang , Xiang Gao

The primary X-ray diagnostic lines in He-like ions are mainly excited by electron impact from the ground level to the n = 2 levels, but at high temperatures n > 2 levels are also excited. In order to describe the atomic processes more…

天体物理学 · 物理学 2009-11-07 Franck Delahaye , Anil K. Pradhan

Elemental abundances can be determined from stellar spectra, making it possible to study galactic formation and evolution. Accurate atomic data is essential for the reliable interpretation and modeling of astrophysical spectra. In this…

太阳与恒星天体物理 · 物理学 2023-09-13 Madeleine Burheim , Henrik Hartman , Hampus Nilsson

We have used an electron beam ion trap to measure electron-density-diagnostic line-intensity ratios for extreme ultraviolet lines from F XII, XIII, and XIV at wavelengths of 185-205 255-276 Angstroms. These ratios can be used as density…

Level energies, wavelengths, electric dipole, magnetic dipole, electric quadrupole, and magnetic quadrupole transition rates, oscillator strengths, and line strengths from combined relativistic configuration interaction and many-body…

We present a theoretical study of the effects and signatures of realistic velocity field and atmospheric inhomogeneities associated with convective motions at the surface of cool late-type stars on the emergent profiles of iron spectral…

太阳与恒星天体物理 · 物理学 2014-03-26 Zazralt Magic , Remo Collet , Martin Asplund

As one of the most important elements in astronomy, iron abundance determinations need to be as accurate as possible. We investigate the accuracy of spectroscopic iron abundance analyses using archetypal metal-poor stars. We perform…

太阳与恒星天体物理 · 物理学 2016-09-15 A. M. Amarsi , K. Lind , M. Asplund , P. S. Barklem , R. Collet

The spectrum of neutral iron is critical to astrophysics, yet furnace laboratory experiments cannot reach many high-lying Fe I levels. Instead, Peterson & Kurucz (2015) and Peterson, Kurucz & Ayres (2017) turned to UV and optical spectra of…

太阳与恒星天体物理 · 物理学 2022-06-29 Ruth C. Peterson , Robert L. Kurucz

Nonlinear interactions between x-rays and long wavelengths can be used as a powerful atomic scale probe for light-matter interactions and for properties of valence electrons. This probe can provide novel microscopic information in solids…

光学 · 物理学 2020-02-19 S. Sofer , O. Sefi , E. Strizhevsky , S. P. Collins , B. Detlefs , Ch. J. Sahle , S. Shwartz

Recent improvements to atomic energy-level data allow, for the first time, accurate predictions to be made for the Fe III line emission strengths in the spectra of luminous, $L_\text{bol}=10^{46}-10^{48}$ erg/s, Active Galactic Nuclei. The…

In the context of observations of the rest-frame ultraviolet and optical emission from distant galaxies, we explore the emission-line properties of photoionization models of active and inactive galaxies. Our aim is to identify new…

星系天体物理 · 物理学 2016-01-20 Anna Feltre , Stephane Charlot , Julia Gutkin

The spectrum of the Fe I atom is critical to many areas of astrophysics and beyond. Measurements of the energies of its high-lying levels remain woefully incomplete, however, despite extensive analysis of ultraviolet laboratory iron…

太阳与恒星天体物理 · 物理学 2015-06-19 Ruth C. Peterson , Robert L. Kurucz

We study the possibility to use line-intensity mapping (LIM) to seek photons from the radiative decay of neutrinos in the cosmic neutrino background. The Standard Model prediction for the rate for these decays is extremely small, but it can…

高能物理 - 唯象学 · 物理学 2021-10-25 José Luis Bernal , Andrea Caputo , Francisco Villaescusa-Navarro , Marc Kamionkowski

Carbon abundances in late-type stars are important in a variety of astrophysical contexts. However C i lines, one of the main abundance diagnostics, are sensitive to departures from local thermodynamic equilibrium (LTE). We present a model…

太阳与恒星天体物理 · 物理学 2019-04-24 A. M. Amarsi , P. S. Barklem , R. Collet , N. Grevesse , M. Asplund

Massive stars drive powerful, supersonic winds via the radiative momentum associated with the thermal UV emission from their photospheres. Shock phenomena are ubiquitous in these winds, heating them to millions, and sometimes tens of…

太阳与恒星天体物理 · 物理学 2015-05-13 David H. Cohen

We present spectrophotometry of 12 Galactic and 3 Magellanic Cloud planetary nebulae (PNe). Nine of the Galactic PNe were observed by scanning the slit across the PN. We use the fluxes of collisionally excited lines (CELs) to derive…

天体物理学 · 物理学 2009-11-07 Y. G. Tsamis , M. J. Barlow , X. -W. Liu , I. J. Danziger , P. J. Storey

Many energy levels of singly ionised iron (Fe II, $Z=26$) remain uncertain or experimentally unknown. Their identification and spectral line data are required in reliable astrophysical spectral analyses. In motivation for improving the…

原子物理 · 物理学 2024-08-16 M. Ding , H. Kozuki , F. Concepcion , G. Nave , J. C. Pickering