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Search Publications by: Alexander Kramida (Fed)

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Displaying 76 - 100 of 150

Re-optimized energy levels and Ritz wavelengths of 198Hg I

May 10, 2011
Author(s)
Alexander Kramida
Energy levels and observed spectral lines of 198Hg I were recently compiled at the National Institute of Standards and Technology (NIST) [E. B. Saloman, J. Phys. Chem. Ref. Data 35, 1519 (2006)]. In that compilation, the energy level values were optimized

The program LOPT for least-squares optimization of energy levels

February 1, 2011
Author(s)
Alexander Kramida
The article describes a program that solves the least-squares optimization problem for finding the energy levels of a quantum-mechanical system based on a set of measured energy separations or wavelengths of transitions between those energy levels, as well

Atomic Spectroscopic Databases at NIST

October 28, 2010
Author(s)
Joseph Reader, Alexander Kramida, Yuri Ralchenko
We present recent work at NIST to develop and maintain databases for spectra, transition probabilities, and energy levels of atoms that are astrophysically important. We also describe our programs to critically compile these data as well as the recently

Revised interpretation of the Na I EUV absorption spectrum

September 27, 2010
Author(s)
Alexander Kramida
Spectral data for neutral sodium were recently compiled by Sansonetti (2008 J. Phys. Chem. Ref. Data 37 1659). In that compilation, some of the energy levels of the 2p53snl configurations were quoted from the studies of the absorption spectrum in the

Extension of the resonance line series of Mg III

December 1, 2009
Author(s)
C M. Brown, Alexander Kramida, Uri Feldman, Joseph Reader
Spectra of Mg emitted by a Penning discharge were recorded in the extreme ultraviolet (EUV) on a 10.7-m grazing-incidence spectrograph with phosphor image plates. The spectra provided nine new lines of Mg III between 156 and 166 Å and allowed us to improve

A Critical Compilation of Energy Levels and Spectral Lines of Neutral Boron

October 16, 2008
Author(s)
Alexander Kramida, A N. Ryabtsev
Observed spectral lines of neutral boron are critically compiled. Fromselected best measurements, an improved and extended set of energy levels isderived for the two most abundant isotopes, 11B and 10B. The ionization energyis determined to a greater

The Ne II Spectrum

October 16, 2008
Author(s)
Alexander Kramida, Gillian Nave
Spectra of neon-filled hollow cathode discharge lamps were observed by means of high-resolution Fourier-transform spectroscopy (FTS) covering the region from vacuum ultraviolet to near infrared. By combining these new measurements with results of other FTS

Extended EUV and UV Spectrum of Ne II

July 1, 2006
Author(s)
Alexander Kramida, C M. Brown, Uri Feldman, Joseph Reader
The extreme ultraviolet (EUV) spectrum of Ne emitted by a Penning discharge has been recorded at high resolution with a 10.7 m grazing incidence spectrometer. Based on the recorded spectra 75 new Ne II lines have been observed between 286 and 325

Energy Levels and Spectral Lines of Ne VIII

June 7, 2006
Author(s)
Alexander Kramida, M-C Buchet-Poulizac
All experimental data on the valence-shell-excited and inner-shell-excited spectra of Li-like neon, including previously unpublished beam-foil spectroscopy data, have been compiled and critically evaluated. Seventeen spectral lines have been newly

Energy Levels and Spectral Lines of Ne VII

February 8, 2006
Author(s)
Alexander Kramida, M-C Buchet-Poulizac
All experimental data on Ne VII, including previously unpublished beam-foil spectroscopy data, have been compiled and critically evaluated. More than a hundred spectral lines have been newly identified. For 40 transitions, the previous identifications have