Stark width measurements of Fe II lines with wavelengths in the range 260–300 nm

Abstract

To cite this version:C Aragón, P Vega, J A Aguilera. Stark width measurements of Fe II lines with wavelengths in the range 260300 nm. Journal of Physics B: Atomic, Molecular and Optical Physics, IOP Publishing, 2011, 44 (5) Abstract. The Stark widths of 21 Fe II lines with wavelengths in the range 260-300 nm have been measured using laser-induced plasmas as spectroscopic sources. A set of Fe-Cu samples has been employed to generate the plasmas. To reduce self-absorption, each line has been measured using a different sample, with an iron concentration determined by means of the curve-of-growth methodology. The remaining error due to self-absorption has been estimated as lower than 10 %. Different instants of the plasma evolution, from 0.84 µs to 2.5 µs are included in the measurements. The electron density, in the range (1.6-7.3)×10 17 cm -3 , is determined by the Stark broadening of the H line. Within this range, the Stark widths are found to be proportional to the electron density. The Boltzmann plot method is used to obtain the plasma temperature, which is in the range 12900-15200 K. The Stark widths obtained have been compared with available experimental and theoretical data.

Quantitative analysis by laser-induced breakdown spectroscopy based on generalized curves of growth

“…The experimental setup is the same used in previous works [30,32], so it is only described briefly here. Laser-induced plasmas are generated by a Nd:YAG laser (wavelength 1064 nm, pulse energy 60 mJ, pulse width 4.5 ns), focused at right angles to the sample surface, placed in air at atmospheric pressure.…”

“…A home-made computer program based on least-squares fitting is used to obtain the line intensities and widths from the measured spectra. The electron density of the laser-induced plasma has been measured from the Stark broadening of the H α line by the same procedure described in previous works [30][31][32][33]. The electron density obtained at the time window 1.6-2.0 μs used for detection of ionic lines is (1.8 ± 0.2) × 10 17 cm − 3 .…”

Method for measurement of transition probabilities by laser-induced breakdown spectroscopy based on CSigma graphs–Application to Ca II spectral lines

“…The experimental system is the same used in previous works [20,24], so it is only described briefly. Laserinduced plasmas are generated by focusing a Nd:YAG laser (wavelength 1064 nm, pulse energy 60 mJ, pulse width 4.5 ns) at right angles onto the sample surface, in air at atmospheric pressure.…”

“…The Ca II lines of interest are listed in Table 2, with their transition probabilities and oscillator strengths obtained from the NIST Atomic Database [23]. The Stark widths for most of the Fe II and Ca II lines have been measured in previous works of our group [24][25][26][27]. To illustrate Cσ graphs and their application for transition probability determination, we have calculated one of such graphs including the Fe II reference lines of Table 1 and the Ca II lines numbered 1-5 in Table 2.…”

Division Xii / Commission 14 / Working Group Collision Processes

“…A semi-empirical approach, which uses a set of wave functions obtained from Hartree-Fock relativistic calculations and includes core polarization effects, has been applied to 58 lines of Pb IV (Alonso-Medina Broadening parameters have been obtained experimentally for the following numbers of lines: Bukvić et al 2011), 28 Cd III , Bukvić et al 2009b, 13 Si I, 15 Si II, 28 Si III and 9 Si IV (Bukvić et al 2009a), 29 (Bukvić et al 2008) (Peláez et al 2010b), 38 Xe II (Peláez et al 2009a, Peláez et al 2009b, 10 Xe III (Peláez et al 2009b), 5 Au I and 26 Au II (Djeniže 2009), 9 Sb III (Djeniže 2008), 15 Mn I and 10 Fe I (Zielinska et al 2010), 21 Fe II (Aragón et al 2011) and C I 833.5 nm (Bartecka et al 2011).…”