arXiv subjects

Nils Wauschkuhn

Publications and source records attributed to Nils Wauschkuhn.

4 recordsLinked to original sources

arXiv2023

Experimental determination of ruthenium L-shell fluorescence yields and Coster-Kronig transition probabilities

The L-shell fluorescence yields and the Coster-Kronig factors of ruthenium (and the corresponding uncertainty) were determined for the first time experimentally by applying radiometrically calibrated instrumentation of the Physikalisch-Technische Bundesanstalt. The resulting fluorescence yields ($ω_{L_3}=0.0459(20)$, $ω_{L_2}=0.0415(26)$, $ω_{L_1}=0.0109(9)$) and the Coster-Kronig factors ($f_{23}=0.177(32)$, $f_{13}=0.528(90)$, $f_{12}=0.173(73)$) agree reasonable well with parts of the data from the literature.

physics.atom-ph↗

arXiv2022

Experimental determination of tantalum L-shell fluorescence yields and Coster-Kronig transition probabilities

Using radiometrically calibrated instrumentation of Physikalisch-Technische Bundesanstalt, the L-shell fluorescence yields and Coster-Kronig factors of tantalum (including the uncertainty budget) were experimentally determined based on transmission and X-ray fluorescence experiments. The determined fluorescence yields ($ω_{L3} = 0.247(12)$, $ω_{L2} = 0.278(15)$, $ω_{L1} = 0.157(12)$) were independently validated trough XRR-GIXRF experiments. Both, the Coster-Kronig factors ($f_{23} = 0.123(84)$, $f_{13} = 0.328(152)$, $f_{12} = 0.14(11)$) as well as the fluorescence yields are in good agreement with the most established databases in the field of X-ray fluorescence.

physics.atom-ph↗

arXiv2022

A note on improved stochastic trace estimation for fermionic string fluctuations

We report on the use of a stochastic trace estimator algorithm, based on mutually unbiased bases, for evaluating the trace of a matrix differential operator appearing in the context of lattice simulations for the discretized superstring worldsheet. A study of the variance, in a setup which is slightly modified with respect to the original one, confirms advantages with respect to more traditional methods like the Gaussian estimator.

hep-lat↗

arXiv2021

Experimental and theoretical approaches for determining the K-shell fluorescence yield of carbon

The knowledge of atomic fundamental parameters, such as the fluorescence yields with low uncertainties, is of decisive importance in elemental quantification involving X-ray fluorescence analysis techniques. However, especially for the low-Z elements, the available literature data are either of poor quality, of unknown or very large uncertainty, or both. For this reason, the K-shell fluorescence yield of carbon was determined in the PTB laboratory at the synchrotron radiation facility BESSY II. In addition, theoretical calculations of the same parameter were performed using the multiconfiguration Dirac-Fock method, including relativistic and quantum electrodynamics (QED) corrections. Both values obtained in this work are compared to the corresponding available literature data.

physics.atom-ph↗