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Search Publications by: Alexander Kramida (Fed)

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Displaying 1 - 25 of 79

Legacy of Charlotte Moore Sitterly in the Internet Age

March 19, 2024
Author(s)
Alexander Kramida
Most (yet not all) results of atomic physics research of Charlotte Moore Sitterly (CMS), which was closely connected to astrophysics, are now incorporated in online databases, one of which is the Atomic Spectra Database of the National Institute of

Atomic Spectroscopy

June 25, 2022
Author(s)
William C. Martin, Wolfgang L. Wiese, Alexander Kramida
This chapter outlines the main concepts of atomic structure, with some emphasis on terminology and notation. Atomic radiation is discussed, in particular the wavelengths, intensities, and shapes of spectral lines, and a few remarks are made regarding

Critically Evaluated Spectral Data for Singly Ionized Carbon (C II)

May 4, 2022
Author(s)
Alexander Kramida, K. Haris
All available experimental data on the spectrum of singly ionized carbon have been critically analyzed. Measurement uncertainties of all published studies have been re-assessed. The scope of observational data includes laboratory emission spectra of arcs

Update of Atomic Data for the First Three Spectra of Actinium

April 22, 2022
Author(s)
Alexander Kramida
Abstract: The present article describes a complete re-analysis of all published data on observed spectral lines and energy levels of the first three spectra of actinium (Ac I–III). In Ac I, three previously determined energy levels have been rejected, 12

New analysis of Fe VII

February 5, 2022
Author(s)
Alexander Kramida, A.N. Ryabtsev, Peter R. Young
New spectrograms of multiply ionized iron have been recorded and analyzed, targeting the Fe VII spectrum. As a result, several previously unknown spectral lines and energy levels have been identified in this spectrum. These new data have been analyzed

Spectral Data for Gallium: Ga I through Ga XXXI

October 12, 2021
Author(s)
T Shirai, Joseph Reader, Alexander Kramida, J Sugar
The energy levels and spectral lines of gallium atom in all stages of ionization have been compiled. Experimental data on spectral lines and energy levels exist for spectra Ga I through Ga VII, Ga XXIII through Ga XXVI, and Ga XXX. For Li-like Ga XXIX

Development of NIST Atomic Databases and OnlineTools

September 5, 2020
Author(s)
Yuri Ralchenko, Alexander Kramida
Over the last 25 years, the atomic standard reference databases and online tools developed at the National Institute of Standards and Technology (NIST) provide users around the world with the highest-quality data on various atomic parameters (e.g., level

Wavelength Standards

May 5, 2020
Author(s)
Alexander Kramida
The concept of wavelength standards is briefly explained on an undergraduate student level, and a guide to their current values and sources is given

Isotope shifts in neutral and singly-ionized calcium

January 20, 2020
Author(s)
Alexander Kramida
All available experimental data on isotope shifts and absolute frequency measurements in the optical spectra of Ca I and Ca II are analyzed, and from them complete tables of isotope shifts and energy levels of all Ca isotopes from 36 to 52 are derived. A

Spectrum of Ni V in the Vacuum Ultraviolet

November 27, 2019
Author(s)
Jacob W. Ward, A J. Raassen, Alexander Kramida, Gillian Nave
This work presents 97 remeasured Fe V wavelengths (1200 Å to 1600 Å) and 123 remeasured Ni V wavelengths (1200 Å to 1400 Å) with uncertainties of approximately 2 mÅ. An additional 67 remeasured Fe V wavelengths and 72 remeasured Ni V wavelengths with

Cowan code: 50 years of growing impact on atomic physics

July 2, 2019
Author(s)
Alexander Kramida
The famous Cowan's book "The Theory of Atomic Structure and Spectra" published in 1981 and his suite of computer codes based on it continue to be highly influential in atomic physics and many other researchareas. As of September 2018, there are more than

Revision of the ionization energy of neutral carbon

May 22, 2018
Author(s)
W L. Glab, Haris Kunari, Alexander Kramida
This publication describes a re-analysis of previously published data on neutral carbon (C I) utilizing critically examined and improved values for the line energies of the absorption spectrum of molecular iodine to calibrate the transition energies of C I

CRITICALLY EVALUATED SPECTRAL DATA FOR NEUTRAL CARBON (C I)

November 22, 2017
Author(s)
Haris Kunari, Alexander Kramida
In this critical compilation, all known to us experimental data on the spectrum of neutral carbon were methodically evaluated and supplemented by parametric calculations with Cowan's code. The sources of experimental data vary from laboratory to

Radiative rates of transitions from the 2s2p3 5Sdeg2 state in neutral carbon

November 1, 2017
Author(s)
Alexander Kramida, Haris Kunari
The measured radiative rates of the 2s22p2 3P1,2 – 2s2p3 5S°2 intercombination transitions in neutral carbon reported in the literature are critically evaluated in comparison with theoretical results. The experimental and theoretical values are compared

The Cu II Spectrum

February 24, 2017
Author(s)
Alexander Kramida, Gillian Nave, Joseph Reader
New wavelength measurements in the vacuum ultraviolet (VUV), ultraviolet and visible spectral regions have been combined with available literature data to refine and extend the description of the spectrum of singly ionized copper (Cu II). In the VUV region