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Radiative cooling of C₇⁻
K Najafian1, M S Pettersson1, B Dynefors2
1Department of Physics, University of Gothenburg, 41296 Gothenburg, Sweden.
The Journal of Chemical Physics
|March 18, 2014
Summary
Carbon-7 anion (C₇⁻) neutralization was studied using a storage ring. Measurements confirmed theoretical radiative cooling rates and provided excitation energy distribution data.
Area of Science:
- Chemical Physics
- Atomic and Molecular Physics
- Physical Chemistry
Background:
- Carbon cluster anions are important in astrochemistry and materials science.
- Understanding their stability and cooling mechanisms is crucial for theoretical and experimental studies.
Purpose of the Study:
- To measure the spontaneous and photo-induced neutralization of C₇⁻.
- To determine radiative cooling rates and excitation energy distribution of C₇⁻.
- To validate theoretical predictions of radiative cooling.
Main Methods:
- Utilized an electrostatic storage ring to study C₇⁻ produced via laser ablation.
- Measured spontaneous decay and photo-induced neutralization signals over time (0.5 ms to 35 ms).
- Analyzed signal amplitude and shape dependence on photon wavelength and ion storage time.
Main Results:
- Obtained three independent measurements of radiative cooling rates for C₇⁻.
- Demonstrated that radiative cooling rates match theoretical predictions.
- Measured the excitation energy distribution of the ions.
- Observed dependence of photo-induced signal amplitude on photon wavelength and storage time.
Conclusions:
- The study successfully characterized the radiative cooling of C₇⁻.
- Experimental results align with theoretical oscillator strength predictions.
- Provides valuable data for understanding the energy dynamics of carbon cluster anions.
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