# Attempt to optically excite the nuclear isomer in 229 Th

@article{Stellmer2018AttemptTO,
title={Attempt to optically excite the nuclear isomer in 229 Th},
author={S. Stellmer and G. Kazakov and M. Schreitl and H. Kaser and M. Kolbe and T. Schumm},
journal={Physical Review A},
year={2018},
volume={97},
pages={062506}
}
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… Expand

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