THE Xe VI ULTRAVIOLET SPECTRUM AND THE XENON ABUNDANCE IN THE HOT DO-TYPE WHITE DWARF RE 0503−289

T. RAUCH; D. HOYER; P. QUINET; MARIO GALLARDO; MÓNICA RAINERI

ASTRONOMY AND ASTROPHYSICS

EDP SCIENCES S A

Lugar: Paris; Año: 2015 vol. 577

0004-6361

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 theatomic data that are used for their calculation.Aims.Reliable Xevioscillator strengths are used to identify Xe lines in the ultraviolet spectrum of the DO-type white dwarfRE 0503−289 and to determine its photospheric Xe abundance.Methods.We publish newly calculated oscillator strengths that are based on a recently measured Xevilaboratory line spectrum.These strengths were used to consider their radiative and collisional bound-bound transitions in detail in our NLTE stellar-atmospheremodels to analyze Xevilines exhibited in high-resolution and high S/N UV observations of RE 0503−289.Results.We identify three hitherto unknown Xevilines 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. ObservedXeviline profiles in the ultraviolet spectrum of the white dwarf RE 0503−289 were well reproduced with the newly calculatedXevioscillator strengths.