Shake-off in XFEL heated solid density plasma

G. O. Williams; L. Ansia; M. Makita; P. Estrela; M. Hussain; T. R. Preston; J. Chalupský; V. Hajkova; T. Burian; M. Nakatsutsumi; J. Kaa; Z. Konopkova; N. Kujala; K. Appel; S. Göde; V. Cerantola; L. Wollenweber; E. Brambrink; C. Baehtz; J-P. Schwinkendorf; V. Vozda; L. Juha; H. -K. Chung; P. Vagovic; H. Scott; P. Velarde; U. Zastrau; M. Fajardo

arXiv · 2501.16970

Shake-off in XFEL heated solid density plasma

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Abstract

In atoms undergoing ionisation, an abrupt re-arrangement of free and bound electrons can lead to the ejection of another bound electron (shake-off). The spectroscopic signatures of shake-off have been predicted and observed in atoms and solids. Here, we present the first observation of this process in a solid-density plasma heated by an x-ray free electron laser. The results show that shake-off of L-shell electrons persists up to temperatures of 10 eV at solid density, and follow the probability predicted for solids. This work shows that shake-off should be included in plasma models for the correct interpretation of emission spectra.

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G. O. Williams, L. Ansia, M. Makita, P. Estrela, M. Hussain, T. R. Preston, J. Chalupský, V. Hajkova, T. Burian, M. Nakatsutsumi, J. Kaa, Z. Konopkova, N. Kujala, K. Appel, S. Göde, V. Cerantola, L. Wollenweber, E. Brambrink, C. Baehtz, J-P. Schwinkendorf, V. Vozda, L. Juha, H. -K. Chung, P. Vagovic, H. Scott, P. Velarde, U. Zastrau, M. Fajardo. 2025-01-28. Shake-off in XFEL heated solid density plasma. https://arxiv.org/abs/2501.16970

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