Atomic transitions for the doubly ionized argon spectrum, Ar III

We present new experimental atomic transition values for the atomic emission spectrum of doubly ionized argon, Ar III. In this work we studied 3s23p4 — 3s23p33d, 3s23p4 — 3s23p34s , 3s23p4 — 3s23p34d, 3s23p4 — 3s23p35s, 3s23p33d — 3s23p34p, and 3s23p34s — 3s23p34p transition arrays and 196 lines were identified as new atomic transitions between levels of these configurations. The experimental data were obtained from a capillary-discharge tube. The identifications are supported by multiconfiguration Hartree-Fock relativistic calculations.Centro de Investigaciones ÓpticasFacultad de Ciencias Astronómicas y Geofísica

Atomic transitions for the doubly ionized argon spectrum, Ar III

We present new experimental atomic transition values for the atomic emission spectrum of doubly ionized argon, Ar III. In this work we studied 3s23p4 — 3s23p33d, 3s23p4 — 3s23p34s , 3s23p4 — 3s23p34d, 3s23p4 — 3s23p35s, 3s23p33d — 3s23p34p, and 3s23p34s — 3s23p34p transition arrays and 196 lines were identified as new atomic transitions between levels of these configurations. The experimental data were obtained from a capillary-discharge tube. The identifications are supported by multiconfiguration Hartree-Fock relativistic calculations.Centro de Investigaciones ÓpticasFacultad de Ciencias Astronómicas y Geofísica

Atomic transitions for the doubly ionized argon spectrum, Ar III

We present new experimental atomic transition values for the atomic emission spectrum of doubly ionized argon, Ar III. In this work we studied 3s23p4 — 3s23p33d, 3s23p4 — 3s23p34s , 3s23p4 — 3s23p34d, 3s23p4 — 3s23p35s, 3s23p33d — 3s23p34p, and 3s23p34s — 3s23p34p transition arrays and 196 lines were identified as new atomic transitions between levels of these configurations. The experimental data were obtained from a capillary-discharge tube. The identifications are supported by multiconfiguration Hartree-Fock relativistic calculations.Centro de Investigaciones ÓpticasFacultad de Ciencias Astronómicas y Geofísica

A Portuguese East Indiaman from the 1502-1503 Fleet of Vasco da Gama off Al Hallaniyah Island, Oman: An interim report

Two Portuguese naus from Vasco da Gama's second voyage to India, left behind to disrupt maritime trade between India and the Red Sea, were wrecked in May 1503 off the north-eastern coast of Al Hallaniyah Island, Oman. The ships, Esmeralda and São Pedro, had been commanded by da Gama's maternal uncles, Vicente and Brás Sodré, respectively. A detailed study and scientific analysis of an artefact assemblage recovered during archaeological excavations conducted in Al Hallaniyah in 2013 and 2014 confirms the location of an early 16th-century Portuguese wreck-site, initially discovered in 1998. Esmeralda is proposed as the probable source of the remaining, un-salved wreckage

Weighted oscillator strengths and lifetimes for the SVII spectrum

The weighted oscillator strengths (gf) and the lifetimes presented in this work were carried out in a multiconfiguration Hartree-Fock relativistic approach. In this calculation, the electrostatic parameters were optimized by a least-squares procedure, in order to improve the adjustment to experimental energy levels. This method produces gf-values that are in better agreement with intensity observations and lifetime values that are closer to the experimental ones. In this work, we presented all the experimentally known electric dipole S VII spectral lines

Wavelengths, Energy Levels, Lifetimes, and Weighted Oscillator Strengths for the S VIII Spectrum

The weighted oscillator strengths (gf) and lifetimes for S VIII presented in this work were obtained by a multiconfigurational Hartree-Fock relativistic approach. In this calculation, the electrostatic energy parameters were optimized by a least-squares procedure in order to improve the adjustment to experimental energy levels. The values for gf and lifetimes were then calculated on the basis of these adjusted parameters. New classifications are proposed for energy levels belonging to the 4s and 4d configurations and lines related to them