| Autor: |
Nevar, A., Nedelko, M., Radomzev, A., Tarasenko, N., Savović, Jelena, Kuzmanović, Miroslav M., Ranković, D. |
| Jazyk: |
angličtina |
| Rok vydání: |
2021 |
| Zdroj: |
PHOTONICA2021 : 8th International School and Conference on Photonics and HEMMAGINERO workshop : Abstracts of Tutorial, Keynote, Invited Lectures, Progress Reports and Contributed Papers; August 23-27, 2021; Belgrade |
| Popis: |
For elucidation a possibility to use molecular emission spectra in LIBS analysis of carbon containing materials time and space resolved spectra of laser ablation plasma from graphite were studied. Laser plasma was produced on a rotated graphite target by fundamental harmonic of YAG: Nd3+ laser (Lotis TII) in air at atmospheric pressure. The optical emission spectra were analyzed using a GSM850 Lotis TII monochromator/spectrograph equipped with a CCD detector. The atomic and molecular spectra in the region of emission of molecules C2 (λ = 516,52 nm) and CN (λ = 421,16 nm) were registered by photomultiplier placed behind the interference filter to record the intensity of the selected plasma emission line. The temporal and spatial characteristics of the plasma spectra with special attention to molecular carbon including molecules СN and С2 were analyzed. It was found that the time range of dominance of the C2 and CN emission is related to the stage of the plasma decay (10–20 μs after the action of the laser pulse, depending on the conditions for plasma creating). The atomic emission spectra of the plasma were used to estimate the concentration of electrons and the electron temperature of the plasma. The vibrational temperature of the carbon plasma was determined from the molecular spectrum of the radical СN ((∆ν = 0, -1). The plasma electron concentration and electron temperature as well as vibrational temperature were determined in different zones of the expanding plasma and at different values of laser power densities (2,2·108 ÷ 3,7·108 W/cm2 ) used in experiments. The electron temperature varied in the range 9700 – 10300 K, the electron concentration was estimated to be in the range from 0,8·1018 cm-3 to 8,0·1018 cm-3 , the vibrational temperature of the plasma was 4560 - 7350 K depending on the experimental conditions (laser power density, spatial zone of the plasma plume). VIII International School and Conference on Photonics and HEMMAGINERO workshop : PHOTONICA2021 : book of abstracts; August 23-27, 2021; Belgrade |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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