Attempt to optically excite the nuclear isomer in 229 Th

  title={Attempt to optically excite the nuclear isomer in 229 Th},
  author={Simon Stellmer and Georgy A. Kazakov and Matthias Schreitl and Hendrik Kaser and Michael Kolbe and Thorsten Schumm},
  journal={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… Expand

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