| 1. |
- Johansson, Sveneric, et al.
(författare)
-
The FERRUM Project: New f-value Data for Fe II and Astrophysical Applications
- 2002
-
Ingår i: Physica Scripta. - : Institute of Physics Publishing (IOPP). - 0281-1847 .- 0031-8949 .- 1402-4896. ; T100, s. 71-80
-
Konferensbidrag (refereegranskat)abstract
- We present the FERRUM Project, an international collaboration aiming at a production and evaluation of oscillator strengths (transition probabilities) of selected spectral lines of singly ionized iron group elements, that are of astrophysical relevance. The results obtained include measurements and calculations of permitted and forbidden lines of Fe II. The data have been applied to both emission and absorption lines in astrophysical spectra. We make comparisons between experimental, theoretical and astrophysical f-values. We give a general review of the various measurements, and discuss the UV8 multiplet of Fe II around 1610 Šin detail.
|
|
| 2. |
- Sabel, Hans, et al.
(författare)
-
The FERRUM project: Experimental f-values for 4p-5s transitions in Fe II
- 2001
-
Ingår i: Astronomy & Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 371, s. 360-365
-
Tidskriftsartikel (refereegranskat)abstract
- New measurements of radiative lifetimes of four 3d65s levelsin Fe II at about 10 eV are presented along with absolute oscillator strengths for twenty 4p-5s transitions involving the four levels. The experimental measurements are compared with two different sets oftheoretical calculations. The lines are of particular interest in the modeling of HLyalpha pumped fluorescence of Fe II in astrophysical plasmas.
|
|
| 3. |
- Andersson, Martin, et al.
(författare)
-
Hyperfine induced interference effects in the 4s4d 3D2–4s4f 3F2,3 transitions in Ga II
- 2006
-
Ingår i: Journal of Physics B. - : Bibliopolis, Edizioni di Filosofia e Scienze. - 0953-4075 .- 1361-6455. ; 39:20, s. 4239-4247
-
Tidskriftsartikel (refereegranskat)abstract
- We report relativistic multiconfiguration Dirac–Hartree–Fock calculations of transitions between the hyperfine levels of 4s4f 3F2,3 and 4s4d 3D2 in Ga II. The capacity of two newly developed programs connected to the graspVU package for generating synthetic spectra is explored. The obtained theoretical spectra are compared to Fourier transform spectra and good agreement is found. The importance of hyperfine induced interference effects for the 4s4d 3D2–4s4f 3F2 transitions is pointed out, and the gf values for all the hyperfine transitions are given.
|
|
| 4. |
- Andersson, Martin, et al.
(författare)
-
Hyperfine induced interference effects in the 4s4d D-3(2)-4s4f F-3(2,3) transitions in GaII
- 2006
-
Ingår i: Journal of Physics B: Atomic, Molecular and Optical Physics. - : IOP Publishing. - 0953-4075 .- 1361-6455. ; 39:20, s. 4239-4247
-
Tidskriftsartikel (refereegranskat)abstract
- We report relativistic multiconfiguration Dirac-Hartree-Fock calculations of transitions between the hyperfine levels of 4s4f F-3(2,3) and 4s4d D-3(2) in Ga II. The capacity of two newly developed programs connected to the grasp VU package for generating synthetic spectra is explored. The obtained theoretical spectra are compared to Fourier transform spectra and good agreement is found. The importance of hyperfine induced interference effects for the 4s4d D-3(2)-4s4f F-3(2) transitions is pointed out, and the gf values for all the hyperfine transitions are given.
|
|
| 5. |
|
|
| 6. |
- Jönsson, Per, et al.
(författare)
-
Oscillator strengths and hypertine structures in GaII from multiconfiguration Dirac-Hartree-Fock calculations
- 2006
-
Ingår i: Journal of Physics B: Atomic, Molecular and Optical Physics. - : IOP Publishing. - 0953-4075 .- 1361-6455. ; 39:7, s. 1813-1824
-
Tidskriftsartikel (refereegranskat)abstract
- We report relativistic multiconfiguration Dirac-Hartree-Fock calculations of oscillator strengths and hyperfine structures for a large number of electric dipole transitions in Ga II. Results for the 4s(2) S-1(0)-4s4p 3P(0)(o) hyperfine-induced transition are also given. Core polarization is accounted for by means of explicit CI. To describe spin and orbital polarization, which are important for the hyperfine structures, configuration state functions obtained by single excitations from all core shells are included in the expansions. The computed oscillator strengths for transitions between low-lying states are in good agreement with recent CIV3 calculations. The hyperfine interaction constants are in close agreement with experimental constants derived from Fourier transform spectra.
|
|
| 7. |
- Nilsson, Hampus, et al.
(författare)
-
Measurements of transition probabilities for complex ions
- 2003
-
Ingår i: Physica Scripta. - 0031-8949. ; T105, s. 61-66
-
Tidskriftsartikel (refereegranskat)abstract
- Fourier transform spectroscopy has proven to be a useful toot when measuring wavelengths and branching fractions. The high spectral resolution makes it possible to extend and improve term analyses of complex spectra. We present an overview of our measurements with the Fourier transform spectrometer at Lund Observatory. Much of our work is motivated by astrophysical problems, and we show an application of some of our measurements related to the age determination of the Galaxy.
|
|
| 8. |
- Sabel, Hans, et al.
(författare)
-
Ru II wavelengths and energy levels derived by Fourier transform spectroscopy
- 2002
-
Ingår i: Physica Scripta. - 0031-8949. ; 66:3, s. 238-251
-
Tidskriftsartikel (refereegranskat)abstract
- The RuII spectrum emitted from a hollow cathode discharge has been recorded in the region 12500-55500cm(-1) (8000-1800Angstrom) using a Fourier transform spectrometer. 538 RuII lines have been measured with high accuracy (+/- 0.003-0.020cm(-1)). Improved energy level values have been derived from the lines and 17 new even levels have been found. The level structure has been interpreted by means of parametric calculations.
|
|
| 9. |
- Sabel, Nina, 1973, et al.
(författare)
-
Analysis of some elements in primary enamel during postnatal mineralization.
- 2009
-
Ingår i: Swedish dental journal. - 0347-9994. ; 33:2, s. 85-95
-
Tidskriftsartikel (refereegranskat)abstract
- The primary teeth start to mineralize in utero and continue development and maturation during the first year of life.The aim of this study was to investigate the concentrations of some elements, C, F, Na, Mg, Cl, K and Sr, by secondary ion mass spectrometry (SIMS) in human primary incisors at different stages of mineralization.The teeth derived from an autopsy material from children who had died in sudden infant death.The buccal enamel of specimens from the ages 1, 2, 3, 4, 6 and 19 months, respectively, was analyzed. It was evident that posteruptive effects play an important role in composition of the outermost parts of the enamel. Before the tooth erupts, the concentrations of the elements vary with the maturation grade of the mineralization in the enamel. Sodium was the element with the highest concentration of the measured elements and chlorine was the element of lowest concentration.The 19 month old specimen, considered as the only mature and erupted tooth, showed to differ from the other specimens.The concentration of fluorine, in the 19 month old specimen's outermost surface, is readily seen higher compared with the other specimens at this depth zone. In the 19 month old specimen the concentration of carbon is lower. Potassium, sodium and chlorine have higher concentrations, in general, in the 19 month old specimen compared with the immature specimens. The thickness of the enamel during mineralization was calculated from data from SIMS.The thickness of the buccal enamel of primary incisors seemed to be fully developed between 3-4 months after birth, reaching a thickness of 350-400 microm.
|
|
| 10. |
- Sabel, Nina, 1973, et al.
(författare)
-
Elemental composition of normal primary tooth enamel analyzed with XRMA and SIMS.
- 2009
-
Ingår i: Swedish dental journal. - 0347-9994. ; 33:2, s. 75-83
-
Tidskriftsartikel (refereegranskat)abstract
- There is an interest to analyze the chemical composition of enamel in teeth from patients with different developmental disorders or syndromes and evaluate possible differences compared to normal composition. For this purpose, it is essential to have reference material. The aim of this study was to, by means of X-ray micro analyses (XRMA) and secondary ion mass spectrometry (SIMS), present concentration gradients for C, O, P and Ca and F, Na, Mg, Cl, K and Sr in normal enamel of primary teeth from healthy individuals. 36 exfoliated primary teeth from 36 healthy children were collected, sectioned, and analyzed in the enamel and dentin with X-ray micro analyses for the content of C, O, P and Ca and F, Na MgCl, K and Sr. This study has supplied reference data for C, O, P and Ca in enamel in primary teeth from healthy subjects. No statistically significant differences in the elemental composition were found between incisors and molars.The ratio Ca/P is in concordance with other studies. Some elements have shown statistically significant differences between different levels of measurement. These results may be used as reference values for research on the chemical composition of enamel and dentin in primary teeth from patients with different conditions and/or syndromes.
|
|
