Experimental Stark widths in the Pb IV and Pb V spectra

Abstract

Context. The triply and fourthly ionized lead (Pb IV and Pb V, respectively) spectral line shapes have been investigated in the laboratory helium plasma at electron densities ranging between 5.1 × 10 22 m −3 and 9.1 × 10 22 m −3 and electron temperatures around 22 000 K (±9%), both interesting for astrophysics. Aims. The aim of this work is to present experimental Stark FWHM (full-width at half of the maximum line intensity, W) for 34 spectral lines from Pb IV and 4 spectral lines from Pb V spectra emitted by the pulsed helium discharge, which is optically thin at the wavelengths of the investigated lines. The values presented in this paper are the first published experimental W data in the Pb IV and Pb V spectra. Methods. The lead atoms were sputtered from the cylindrical lead plates that are located in the homogenous part of the pulsed helium discharge at a pressure of 665 Pa in a flowing regime. The Pb IV and Pb V spectral line profiles were recorded using the McPherson model 209 spectrograph and the Andor ICCD camera as the detection system. Results. The Stark FWHMs of 34 Pb IV and 4 Pb V spectral lines were measured in the wavelength interval between 200 nm and 461 nm. Our experimental Pb IV W values are compared with the existing theoretical data. Twenty four Pb IV W values from the above mentioned set haven't been calculated so far. The isotope shift, caused by the four natural Pb isotopes, and the hyperfine structure have no influence on the observed symmetry of the measured Pb IV and Pb V line shapes at our plasma parameters. Conclusions. At the mentioned plasma parameters we found a tolerable agreement (within the accuracy of the experiment and uncertainties of the theoretical approaches used) between the measured and calculated ten Pb IV W values. For the Pb V spectral lines no comparison is possible because as far as we are aware, no experimental and theoretical W data exist.

Theoretical Stark broadening parameters of Pb vspectral lines

“…In Table 5, we present a comparison between our values of FWHM of Pb v spectral lines and the four experimental values of Bukvic et al (2011). In this table, we present our calculated values in two columns: the first are the theoretical FWHM that are displayed in Table 4.…”

“…Stark widths and shifts are presented for an electron density of 10 17 cm~3 and temperatures T = 1.6-5.0 (10 4 K). The values presented in this work are compared with the values presented by Bukvic et al (2011) for the 2142.5, 2167.9 and 2278.6 Á lines of Pb v. *E-mail: cristobal.colon@upm.es…”

“…In a recent work, Bukvic et al (2011) have measured the Stark broadening of several spectral lines of Pb iv and Pb v in a pulsed helium plasma discharge. The presence of Pb iv in stellar spectra has been reported in a few different types of stars: Proffltt, Sansonetti & Reader (2001) have determined the abundance of lead in the early B main-sequence star AV 304 in the Small Magellanic Cloud by measuring the 1313.1 A resonance line of Pb iv.…”

Division Xii / Commission 14 / Working Group Collision Processes

“…Pb V (Bukvić et al 2011), 28 Cd III (Djeniže et al 2009, 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) (Aragón et al 2011) and C I 833.5 nm (Bartecka et al 2011).…”

“…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).…”