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Related papers: Nitrogen K-shell photoabsorption

200 papers

The results of K-band-imaging observations of a candidate of an absorbed QSO at z=0.653, AX J131831+3341, are presented. The B-K color of the object is 4.85 mag, which is much redder than optically-selected QSOs. The K-band image shows…

Astrophysics · Physics 2015-06-24 Masayuki Akiyama , Kouji Ohta

Our recent re-analysis of the solar photospheric spectra with non-local thermodynamic equilibrium (non-LTE) models resulted in higher metal abundances compared to previous works. When applying the new chemical abundances to Standard Solar…

Solar and Stellar Astrophysics · Physics 2022-09-07 Manuel A. Bautista , Maria Bergemann , Helena Carvajal Gallego , Sébastien Gamrath , Patrick Palmeri , Pascal Quinet

X-ray absorption spectroscopy is a crucial experimental technique for elucidating the mechanisms of structural degradation in battery materials. However, extracting information from the measured spectrum is challenging without high-quality…

We present a model for electron scattering off nuclei and photon absorption in the resonance energy region (W <= 2 GeV). The elementary gamma/gamma* N-vertex is described using in-medium kinematics and up-to-date form factors for…

Nuclear Theory · Physics 2008-09-16 O. Buss , T. Leitner , U. Mosel , L. Alvarez-Ruso

We present a wide grid of models for the structure and transmission properties of warm absorbers in active galactic nuclei (AGN). Contrary to commonly used constant density models, our absorbing cloud is assumed to be under constant total…

Astrophysics · Physics 2007-05-23 A. Rozanska , R. Goosmann , A. -M. Dumont , B. Czerny

Neutral nickel (Ni I) is abundant in the solar atmosphere and is one of the important elements that contribute to the emission and absorption of radiation in the spectral range between 1900 and 3900 A. Previously, the Solar Radiation…

Solar and Stellar Astrophysics · Physics 2015-06-15 Mariela C. Vieytes , Juan M. Fontenla

We present multi-configuration Breit-Pauli distorted-wave photoionization (PI) cross sections and radiative recombination (RR) and dielectronic recombination (DR) rate coefficients for the first six krypton ions. These were calculated with…

Solar and Stellar Astrophysics · Physics 2015-05-28 N. C. Sterling

The absorption of infrared and visible radiation from stellar emission spectra by the negatively charged hydrogen ions H$^{-}$ is considered. We derive the explicit formulas for the bound-free absorption coefficient $a_{\nu}$ for the…

Solar and Stellar Astrophysics · Physics 2013-12-11 Alexei M. Frolov

We use the Breit Pauli $R$-matrix method to calculate accurate energies and radiative data for states in C I up to $n$=30 and with $l\le 3$. We provide the full dataset of decays to the five 2s$^2$2p$^2$ ground configuration states…

Solar and Stellar Astrophysics · Physics 2023-08-11 P. J. Storey , R. P. Dufresne , G. Del Zanna

The recent and older level shifts and widths in pbar atoms are analyzed. The results are fitted by an antiproton-nucleus optical potential with two basic complex strength parameters. These parameters are related to average S and P wave…

Nuclear Theory · Physics 2008-11-26 S. Wycech , F. J. Hartmann , J. Jastrzebski , B. Klos , A. Trzcinska , T. von Egidy

We develop a theoretical model for calibrating the absorption imaging of cold atoms under high magnetic fields. Comparing to zero or low magnetic fields, the efficiency of the absorption imaging becomes lower while it requires an additional…

Atomic Physics · Physics 2023-07-20 Yuqi Liu , Zhongchi Zhang , Shiwan Miao , Zihan Zhao , Huaichuan Wang , Wenlan Chen , Jiazhong Hu

Although electron energy loss near edge structure analysis provides a tool for experimentally probing unoccupied density of states, a detailed comparison with simulations is necessary in order to understand the origin of individual peaks.…

Reliable fundamental parameters are essential for accurate X-ray fluorescence analysis of sodium. This work presents updated experimental values with reliable uncertainties for sodium K-shell fundamental parameters such as: fluorescence…

Atomic Physics · Physics 2025-06-18 Marie-Louis Venzke , Katja Frenzel , Philipp Hönicke

The advent of the X-ray microcalorimeter spectrometer Resolve onboard the XRISM space telescope opened a new era for high-resolution X-ray spectroscopy of astrophysical plasmas. Many spectral features were newly detected, including the K…

A detailed analysis of the radiative and Auger de-excitation channels of K-shell vacancy states in Fe II-Fe IX has been carried out. Level energies, wavelengths, A-values, Auger rates and fluorescence yields have been calculated for the…

Astrophysics · Physics 2009-11-07 P. Palmeri , C. Mendoza , T. R. Kallman , M. A. Bautista , M. Melendez

Vibrationally resolved near-edge x-ray absorption spectra at the K-edge for a number of small molecules have been computed from anharmonic vibrational configuration interaction calculations of the Franck-Condon factors. The potential energy…

Chemical Physics · Physics 2021-02-03 Torsha Moitra , Diana Madsen , Ove Christiansen , Sonia Coriani

We present results for the optical absorption spectra of small-diameter single-wall carbon and boron nitride nanotubes obtained by {\it ab initio} calculations in the framework of time-dependent density functional theory. We compare the…

Materials Science · Physics 2010-07-01 A. G. Marinopoulos , Ludger Wirtz , Andrea Marini , Valerio Olevano , Angel Rubio , Lucia Reining

[Abridged] Investigations of neutron(n)-capture element nucleosynthesis and chemical evolution have largely been based on stellar spectroscopy. However, the recent detection of these elements in several planetary nebulae (PNe) indicates…

Thanks to the recent availability of large surveys, there has been renewed interest in third-order correlation statistics. Measures of third-order clustering are sensitive to the structure of filaments and voids in the universe and are…

Astrophysics · Physics 2010-11-11 J. M. Loh

Recently an accurate analysis of absorption spectra of molecular hydrogen, observed with the Cosmic Origins Spectrograph aboard the Hubble Space Telescope, in the photosphere of white dwarf stars GD133 and GD29-38 was published in a Letter…

Atomic Physics · Physics 2015-06-23 E. J. Salumbides , J. Bagdonaite , H. Abgrall , E. Roueff , W. Ubachs