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Line-intensity mapping (LIM) provides a promising way to probe cosmology, reionization and galaxy evolution. However, its sensitivity to cosmology and astrophysics at the same time is also a nuisance. Here we develop a comprehensive…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-21 José Luis Bernal , Patrick C. Breysse , Héctor Gil-Marín , Ely D. Kovetz

Recent state-of-the-art calculations of A-values and electron impact excitation rates for Fe III are used in conjunction with the Cloudy modeling code to derive emission line intensity ratios for optical transitions among the fine-structure…

Using photoemission intensities and a detection system employed by many groups in the electron spectroscopy community as an example, we have quantitatively characterized and corrected detector non-linearity effects over the full dynamic…

Instrumentation and Detectors · Physics 2007-05-23 N. Mannella , S. Marchesini , A. W. Kay , A. Nambu , T. Gresch , S. -H. Yang , B. S. Mun , J. M. Bussat , A. Rosenhahn , C. S. Fadley

Radiation contributes to the acceleration of large-scale flows in various astrophysical environments because of the strong opacity in spectral lines. Quantification of the associated force is crucial to understanding these line-driven…

Solar and Stellar Astrophysics · Physics 2021-03-31 Aylecia S. Lattimer , Steven R. Cranmer

Strong wind-wind collisions in massive binaries generate a very hot plasma that frequently produces a moderately strong iron line. The morphology of this line depends upon the properties of the wind interaction zone and its orientation with…

Solar and Stellar Astrophysics · Physics 2020-12-09 Gregor Rauw , Enmanuelle Mossoux , Yael Naze

In accelerating and supersonic media, the interaction of photons with spectral lines can be of ultimate importance. However, fully accounting for such line forces currently can only be done by specialised codes in 1-D steady-state flows.…

Solar and Stellar Astrophysics · Physics 2022-11-16 L. G. Poniatowski , N. D. Kee , J. O. Sundqvist , F. A. Driessen , N. Moens , S. P. Owocki , K. G. Gayley , L. Decin , A. de Koter , H. Sana

An analysis is made of the effect of a strong field on the shape of the amplification spectral line for mono-velocity V-type three-level atoms. There are three strong-field contributions, differing in their dependence on the set of…

Quantum Physics · Physics 2007-05-23 T. Ya. Popova , A. K. Popov

Fully relativistic calculations of radiative rates and electron impact excitation cross sections for Fe X are used to derive theoretical emission-line ratios involving transitions in the 174-366 A wavelength range. A comparison of these…

Astrophysics · Physics 2009-11-13 F P Keenan , D B Jess , K M Aggarwal , R J Thomas , J W Brosius , J M Davila

Our ability to model the shapes and strengths of iron lines in the solar spectrum is a critical test of the accuracy of the solar iron abundance, which sets the absolute zero-point of all stellar metallicities. We use an extensive 463-level…

Solar and Stellar Astrophysics · Physics 2017-05-31 K. Lind , A. M. Amarsi , M. Asplund , P. S. Barklem , M. Bautista , M. Bergemann , R. Collet , D. Kiselman , J. Leenaarts , T. M. D. Pereira

Recent theory progresses in (3+1)D dynamical descriptions of relativistic nuclear collisions at finite baryon density are reviewed. Heavy-ion collisions at different collision energies produce strongly coupled nuclear matter to probe the…

Nuclear Theory · Physics 2022-02-16 Chun Shen

Fe II emission lines are observed from nearly all classes of astronomical objects over a wide spectral range from the infrared to the ultraviolet. To meaningfully interpret these lines, reliable atomic data are necessary. In work presented…

Atomic Physics · Physics 2019-03-12 Yier Wan , C. Favreau , S. D. Loch , B. M. McLaughlin , Yueying Qi , P. C. Stancil

We show that the nonlinear interactions between x rays and longer wavelengths in crystals depend strongly on the band structure and related properties. Consequently, these types of interactions can be used as a powerful probe for…

Optics · Physics 2019-12-04 Ron Cohen , Sharon Shwartz

We present laboratory spectra of the $3p$--$3d$ transitions in Fe$^{14+}$ and Fe$^{15+}$ excited with a mono-energetic electron beam. In the energy dependent spectra obtained by sweeping the electron energy, resonant excitation is confirmed…

The energies and widths of gamma-ray lines emitted by ambient nuclei excited by flare-accelerated protons and alpha particles provide information on the ions directionality and spectra, and on the characteristics of the interaction region.…

Astrophysics · Physics 2009-11-07 G. H. Share , R. J. Murphy , J. Kiener , N. de Sereville

Non-linear effects in accelerator physics are important for both successful operation of accelerators and during the design stage. Since both of these aspects are closely related, they will be treated together in this overview. Some of the…

Accelerator Physics · Physics 2016-01-22 W. Herr

We present theoretical iron emission line strengths for physical conditions typical of Active Galactic Nuclei with Broad-Line Regions. The non-local thermodynamic equilibrium (NLTE) models include a new and extensive treatment of radiative…

Astrophysics · Physics 2009-11-10 T. A. A. Sigut , Anil K. Pradhan , Sultana N. Nahar

In this work we present a study of the strong optical collisional emission lines of Ne and Ar in an heterogeneous sample of ionized gaseous nebulae for which it is possible to derive directly the electron temperature and hence the chemical…

The radiation force on a single electron in an ultraintense plane wave ($a = eE/mc\omega \sim 1$) is calculated and shown to be proportional to $a^4$ in the high-$a$ limit for arbitrary waveform and polarization. The cyclotron motion of an…

Plasma Physics · Physics 2009-10-31 Joel E. Moore

The three Mn I lines at 17325, 17339 and 17349 \AA~are among the 25 strongest lines ($\log(gf)>0.5$) in the H-band. They are all heavily broadened due to hyperfine structure and the profiles of these lines have so far not been understood.…

Solar and Stellar Astrophysics · Physics 2015-06-19 Martin Andersson , Jon Grumer , Nils Ryde , Richard Blackwell-Whitehead , Roger Hutton , Yaming Zou , Per Jönsson , Tomas Brage

We consider three recent large-scale calculations for the radiative and electron-impact excitation data of N IV, carried out with different methods and codes. The scattering calculations employed the relativistic Dirac $R$-matrix (DARC)…

Solar and Stellar Astrophysics · Physics 2019-02-20 G. Del Zanna , L. Fernandez-Menchero , N. R. Badnell