High precision x-ray spectroscopy on highly charged argon ions

High-precision wavelength measurements on the 1s2s ³S₁ \rightarrow 1s^{2 1}S₀ ($z$'') and 1s2p ¹P₁ \rightarrow 1s^{2 1}S₀ ($w$'') transitions in Ar¹⁶⁺ as well as of the Lyman-α₁ transition in Cl¹⁶⁺ with respect to the Lyman-α₁ transition in Ar¹⁷⁺ were carried out, using a new flat crystal spectrometer installed at the Heidelberg electron beam ion trap (HD-EBIT). A novel, highly accurate technique of Bragg-angle determination was developed, employing two beams of visible light reflected on the x-ray crystal to mark the x-ray reflection position. The need for collimating entrance slits causing unacceptable x-ray flux losses is thereby avoided. Relative uncertainties of better than \Delta \lambda / \lambda < 10^-5 were achieved in the measurement of all three lines. The measured Cl¹⁶⁺ Lyman-α₁ transition energy is in perfect agreement with the theoretical prediction and previous experimental work, however $4$ times more accurate. The $z$ transition energy, never measured before in argon, agrees with predictions within its error bar. The $w$ transition energy, while in perfect agreement with but two times more accurate than earlier experimental results, disagrees with by 2σ with predictions, pointing at their possible incompleteness.

Level thesis:degree_level

thesis.doctoral

Grantor dc:publisher

Universität Heidelberg

Year

2005

Author dc:creator

• Bruhns, Hjalmar

Contributors dc:contributor

• Ullrich, Joachim

Repository record source_url

http://www.ub.uni-heidelberg.de/archiv/6085

OAI identifier oai:identifier

oai:archiv.ub.uni-heidelberg.de:6085