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DOE OSTI · 1360176

Nonsequential two-photon absorption from the K shell in solid zirconium

Ghimire, Shambhu·Fuchs, Matthias·Hastings, Jerry·Herrmann, Sven C.·Inubushi, Yuichi·Pines, Jack·Shwartz, Sharon·Yabashi, Makina·Reis, David A.
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Abstract

Here, we report the observation of nonsequential two-photon absorption from the K shell of solid Zr (atomic number Z=40) using intense x-ray pulses from the Spring-8 Angstrom Compact Free-Electron Laser (SACLA). We determine the generalized nonlinear two-photon absorption cross section at the two-photon threshold in the range of 3.9–57 ×10 –60 cm 4 s bounded by the estimated uncertainty in the absolute intensity. The lower limit is consistent with the prediction of 3.1 ×10 –60 cm 4 s from the nonresonant Z –6 scaling for hydrogenic ions in the nonrelativistic, dipole limit.

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74 ATOMIC AND MOLECULAR PHYSICS

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BibTeXRIS

Ghimire, Shambhu, Fuchs, Matthias, Hastings, Jerry, Herrmann, Sven C., Inubushi, Yuichi, Pines, Jack, Shwartz, Sharon, Yabashi, Makina, Reis, David A.. 2016-10-21. Nonsequential two-photon absorption from the K shell in solid zirconium. https://doi.org/10.1103/physreva.94.043418

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