# Attempt to optically excite the nuclear isomer in Th229

@article{Stellmer2018AttemptTO,
title={Attempt to optically excite the nuclear isomer in
Th229},
author={Simon Stellmer and G A Kazakov and Matthias Schreitl and Hendrik Kaser and Michael Kolbe and Thorsten Schumm},
journal={Physical Review A},
year={2018}
}
• Published 25 March 2018
• Physics
• Physical Review A
We aim to perform direct optical spectroscopy of the $^{229}\mathrm{Th}$ nuclear isomer to measure its energy and lifetime, and to demonstrate optical coupling to the nucleus. To this end, we develop $^{229}\mathrm{Th}$-doped ${\mathrm{CaF}}_{2}$ crystals, which are transparent at the anticipated isomer wavelength. Such crystals are illuminated by tunable VUV undulator radiation for direct excitation of the isomer. We scan a $\ifmmode\pm\else\textpm\fi{}5\ensuremath{\sigma}$ region around the…

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