Stellar laboratories

Abstract

Context. For the spectral analysis of spectra of hot stars with a high resolution and high signal-to-noise ratio (S/N), advanced nonlocal thermodynamic equilibrium (NLTE) model atmospheres are mandatory. These are strongly dependent on the reliability of the atomic data that are used for their calculation.Aims. Reliable Xe vi oscillator strengths are used to identify Xe lines in the ultraviolet spectrum of the DO-type white dwarf RE 0503−289 and to determine its photospheric Xe abundance.Methods. We publish newly calculated oscillator strengths that are based on a recently measured Xe vi laboratory line spectrum.These strengths were used to consider their radiative and collisional bound-bound transitions in detail in our NLTE stellar-atmosphere models to analyze Xe vi lines exhibited in high-resolution and high S/N UV observations of RE 0503−289. Results. We identify three hitherto unknown Xe vi lines in the ultraviolet spectrum of RE 0503−289 and confirm the previously measured photospheric Xe abundance of this white dwarf (log Xe = −4.2 ± 0.6 by mass). Conclusions. Reliable measurements and calculations of atomic data are prerequisite for stellar-atmosphere modeling. Observed Xe vi line profiles in the ultraviolet spectrum of the white dwarf RE 0503−289 were well reproduced with the newly calculated Xe vi oscillator strengths.

Stellar laboratories

“…Like Mo, Kr, and Xe exhibit prominent lines in the UV spectra of RE 0503−289, but not in those of G191−B2B. To investigate on their abundances, we individually included Kr and Xe in our G191−B2B models and calculated theoretical profiles for all Kr and Xe lines that were identified in RE 0503−289 (Werner et al 2012b;Rauch et al 2015a). An upper Kr abundance limit of 10 times solar (1.09 × 10 −6 by mass) is determined from lines of Kr vi-vii simultaneously (Fig.…”

Stellar laboratories

“…8) based on atomic data available at that time. Calculations of transition probabilities for Zn, Ga, Ge, Kr, Mo, Xe, and Ba in the subsequent years allowed precise abundance measurements for these elements (Rauch et al 2014a(Rauch et al , 2015b(Rauch et al , 2012(Rauch et al , 2016a(Rauch et al , 2014b(Rauch et al , 2015a(Rauch et al , 2016b.…”

Spectral Analysis of Moderately Charged Rare-Gas Atoms

“…The Xe VI analysis is difficult because of the strong mixing of level composition and the non-smooth behavior of the structure which together result in changes in level positions and composition along the isoelectronic sequence. By using all this research, a new paper on the Xe VI ultraviolet spectrum and the xenon abundance in the hot DO-type white dwarf RE 0503-289 was also reported [44].…”