Accurate and experimentally validated transition data for Si I and Si II
Pehlivan Rhodin, A. LU ; Hartman, H. LU
; Nilsson, H.
LU
and Jönsson, P.
(2024)
In Astronomy and Astrophysics
682.
- Abstract
Aims. The aim of this study is to provide radiative data for neutral and singly ionised silicon, in particular for the first experimental oscillator strengths for near-infrared Si I lines. In addition, we aim to perform atomic structure calculations both for neutral and singly ionised silicon while including lines from highly excited levels. Methods. We performed large-scale atomic structure calculations with the relativistic multiconfiguration Dirac-Hartree-Fock method using the GRASP2K package to determine log(ð A) values of Si I and Si II lines, taking into account valence-valence and core-valence electron correlation. In addition, we derived oscillator strengths of near-infrared Si I lines by combining the experimental branching... (More)
Aims. The aim of this study is to provide radiative data for neutral and singly ionised silicon, in particular for the first experimental oscillator strengths for near-infrared Si I lines. In addition, we aim to perform atomic structure calculations both for neutral and singly ionised silicon while including lines from highly excited levels. Methods. We performed large-scale atomic structure calculations with the relativistic multiconfiguration Dirac-Hartree-Fock method using the GRASP2K package to determine log(ð A) values of Si I and Si II lines, taking into account valence-valence and core-valence electron correlation. In addition, we derived oscillator strengths of near-infrared Si I lines by combining the experimental branching fractions with radiative lifetimes from our calculations. The silicon plasma was obtained from a hollow cathode discharge lamp, and the intensity-calibrated high-resolution spectra between 1037 and 2655 nm were recorded by a Fourier transform spectrometer. Results. We provide an extensive set of accurate experimental and theoretical log(ðA) values. For the first time, we derived 17 log(ðA) values of Si I lines in the infrared from experimental measurements. We report data for 1500 Si I lines and 500 Si II lines. The experimental uncertainties of our A-values vary between 5% for the strong lines and 25% for the weak lines. The theoretical log(ð A) values for Si I lines in the range 161 nm to 6340 nm agree very well with the experimental values of this study and complete the missing transitions involving levels up to 3s23p7s (61 970 cm' 1). In addition, we provide accurate calculated log(ðA) values of Si II lines from the levels up to 3s27f (122 483 cm' 1) in the range 81 nm to 7324 nm.
(Less)
- author
- Pehlivan Rhodin, A.
LU
; Hartman, H.
LU
; Nilsson, H.
LU
and Jönsson, P.
- organization
- publishing date
- 2024-02
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Atomic data, Methods: laboratory: atomic, Methods: numerical, Techniques: spectroscopic
- in
- Astronomy and Astrophysics
- volume
- 682
- article number
- A184
- publisher
- EDP Sciences
- external identifiers
-
- scopus:85186144682
- ISSN
- 0004-6361
- DOI
- 10.1051/0004-6361/202245686
- language
- English
- LU publication?
- yes
- id
- 00fb29ce-c840-44e5-9620-59e7ce661549
- date added to LUP
- 2024-03-27 15:32:02
- date last changed
- 2024-03-28 06:52:44
@article{00fb29ce-c840-44e5-9620-59e7ce661549,
abstract = {{<p>Aims. The aim of this study is to provide radiative data for neutral and singly ionised silicon, in particular for the first experimental oscillator strengths for near-infrared Si I lines. In addition, we aim to perform atomic structure calculations both for neutral and singly ionised silicon while including lines from highly excited levels. Methods. We performed large-scale atomic structure calculations with the relativistic multiconfiguration Dirac-Hartree-Fock method using the GRASP2K package to determine log(ð A) values of Si I and Si II lines, taking into account valence-valence and core-valence electron correlation. In addition, we derived oscillator strengths of near-infrared Si I lines by combining the experimental branching fractions with radiative lifetimes from our calculations. The silicon plasma was obtained from a hollow cathode discharge lamp, and the intensity-calibrated high-resolution spectra between 1037 and 2655 nm were recorded by a Fourier transform spectrometer. Results. We provide an extensive set of accurate experimental and theoretical log(ðA) values. For the first time, we derived 17 log(ðA) values of Si I lines in the infrared from experimental measurements. We report data for 1500 Si I lines and 500 Si II lines. The experimental uncertainties of our A-values vary between 5% for the strong lines and 25% for the weak lines. The theoretical log(ð A) values for Si I lines in the range 161 nm to 6340 nm agree very well with the experimental values of this study and complete the missing transitions involving levels up to 3s<sup>2</sup>3p7s (61 970 cm<sup>' 1</sup>). In addition, we provide accurate calculated log(ðA) values of Si II lines from the levels up to 3s<sup>2</sup>7f (122 483 cm<sup>' 1</sup>) in the range 81 nm to 7324 nm.</p>}},
author = {{Pehlivan Rhodin, A. and Hartman, H. and Nilsson, H. and Jönsson, P.}},
issn = {{0004-6361}},
keywords = {{Atomic data; Methods: laboratory: atomic; Methods: numerical; Techniques: spectroscopic}},
language = {{eng}},
publisher = {{EDP Sciences}},
series = {{Astronomy and Astrophysics}},
title = {{Accurate and experimentally validated transition data for Si I and Si II}},
url = {{http://dx.doi.org/10.1051/0004-6361/202245686}},
doi = {{10.1051/0004-6361/202245686}},
volume = {{682}},
year = {{2024}},
}