We measured the fluorescence photon yield of neon upon soft x-ray ionization (~1200 eV) from the x-ray free electron laser at Linac Coherent Light Source, and demonstrated the usage of a grazing incidence spectrometer with a variable linespacing grating to perform x-ray fluorescence spectroscopy on a gas phase system. Our measurements also allowed us to estimate the focal size of the beam from the theoretical description developed, in terms of the rate equation approximation accounting for photoionization shake-off of neutral neon and double Auger decay of single core holes.
@article{arxiv.1708.01283,
title = {LCLS in - photon out: fluorescence measurement of neon using soft x-rays},
author = {Razib Obaid and Christian Buth and Georgi L. Dakovski and Randolf Beerwerth and Michael Holmes and Jeff Aldrich and Ming-Fu Lin and Michael Minitti and Timur Osipov and William Schlotter and Lorenz S. Cederbaum and Stephan Fritzsche and Nora Berrah},
journal= {arXiv preprint arXiv:1708.01283},
year = {2018}
}