Spectroscopic temperature measurements in a decaying laser-induced plasma using the C2 Swan system

CN and C2 vibrational spectra analysis in molecular LIBS of organic materials

“…The vibrational temperatures for CN violet and C 2 Swan bands systems were determined by a least-square fitting program NMT applying the Nelder-Mead algorithm, developed at the University of Tennessee Space Institute [35][36][37][38][39]. This program is used in producing theory spectra for the selected diatomic molecular transitions and wavelength regions.…”

“…This program is used in producing theory spectra for the selected diatomic molecular transitions and wavelength regions. It uses accurate line strengths (Hönl-London) factors, along with temperature and full-width halfmaximum (FWHM) values as inputs [35][36][37][38][39]. For instance, Fig.…”

Atomic and molecular emissions in laser-induced breakdown spectroscopy

“…Atomic spectral bases are usually available in the so-called National Institute of Standards and Technology (NIST) database [14]. Molecular data can be found in Herzberg's works; however, frequently accurate databases are required for analytic studies that have become available recently, e.g., for select transitions of diatomic molecules of interest that include diatomic CN, C 2 , AlO molecular transitions [15][16][17][18] amongst other diatomic molecules. Recently, detailed C 2 [19][20][21][22][23][24], Titanium Monoxide TiO [25][26][27] spectra including a study of femto-second versus nano-second laser ablation [28], and AlO emission spectra of the B 2 Σ + → X 2 Σ + [29,30] transition were communicated.…”

Femtosecond laser induced breakdown for combustion diagnostics

“…[26][27][28] Moreover, the OH (A 2 R þ -X 2 P) emission at 307.8 nm has been also clearly observed, even after some delay time, while the weak bands appearing at the spectral regions 564-550 nm, 517-510 nm, and 474-465 nm belong to the C 2 (d 3 P g -a 3 P u ) Swan band system. 25,29 These spectral features are better resolved in Figure 2 measured with a delay time of 230 ns. Finally, the spectral lines of atomic nitrogen at 744.2, 821.6, and 871.2 nm and of atomic oxygen at 777 and 844.6 nm, which have been previously observed in the atmospheric air LIBS spectra, have also been found to appear in the LIBS spectra of the flame although significantly weaker.…”

“…19,[23][24][25] These new features have been attributed to the atomic hydrogen Balmer lines H a at 656.3 and H b at 486.1 nm, and the CN molecular emission at about 388.3 nm, corresponding to the (0,0) band head of the violet CN system corresponding to the transition B 2 R þ -X 2 R þ . In addition to these prominent features, several other spectral features, exhibiting however a weaker intensity have been clearly observed in these emission spectra.…”