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Updated: Jun 16, 2026
09:40
Measurement and Analysis of Atomic Hydrogen and Diatomic Molecular AlO, C2, CN, and TiO Spectra Following Laser-induced Optical Breakdown
Published on: February 14, 2014
Summary
Laser power densities for Lyman and Werner bands were calculated. Lyman band transitions are stronger, despite Werner band excitation, due to lower ground state population reducing net inversion density.
Area of Science:
- Spectroscopy
- Atomic and Molecular Physics
Background:
- Understanding molecular hydrogen (H2) spectroscopy is crucial for astrophysics and plasma physics.
- Lyman and Werner bands are key electronic transitions in H2, relevant to various physical conditions.
Purpose of the Study:
- To calculate laser power densities for Lyman and Werner bands using rotational analysis.
- To compare the strengths and population dynamics of transitions within these bands.
Main Methods:
- Performed a complete rotational analysis of the Lyman and Werner bands.
- Calculated laser power densities based on the rotational analysis.
Main Results:
- Lyman band transitions, specifically P(3) and P(1), were found to be stronger than Werner band transitions (Q(1), P(3)).
- Despite higher excitation favoring Werner transitions, their termination on lower ground state vibrational levels reduced net inversion density.
- This population dynamics significantly impacts the observed band strengths.
Conclusions:
- The relative strengths of Lyman and Werner bands are influenced by rotational population distributions and ground state vibrational populations.
- Laser power densities are critically dependent on these spectroscopic and population factors.
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