17 Zhu, B. Gumberidze, Alexandre Over, T. Weber, G. Andelkovic, Z. Bräuning-Demian, A. Chen, R. J. Dmytriiev, D. Forstner, Oliver Hahn, Christoph Herfurth, F. Herdrich, Marc Oliver Hillenbrand, Pierre-Michel Kalinin, A. Kröger, F. M. Lestinsky, Michael Litvinov, Yu. A. Menz, Esther Babette Middents, W. Morgenroth, T. Petridis, N. Pfäfflein, Philip Sanjari, M. S. Sidhu, Ragandeep Singh Spillmann, U. Schuch, R. Schippers, S. Trotsenko, S. Varga, Laszlo Vorobyev, G. Stöhlker, Thomas HIJ ATP DEC FHF Physical review / A Physical review / A APS Woodbury, NY 2469-9926 10.1103/PhysRevA.105.052804 English 052804 5 105 For bare lead ions, decelerated to the low beam energy of 10 MeV/u, the x-ray emission associated with radiative recombination (RR) at 'cold collision' conditions has been studied at the electron cooler of CRYRING@ESR at GSI-Darmstadt. Utilizing dedicated x-ray detection chambers installed at 0° and 180° observation geometry, we observed for the very first time for stored ions the full x-ray emission spectrum associated with RR under electron cooling conditions. Most remarkably, no line distortion effects due to delayed emission are present in the well resolved spectra, spanning over a wide range of x-ray energies (from about 5 to 100 keV) which enable to identify fine-structure resolved Lyman, Balmer as well as Paschen x-ray lines along with the RR transitions into the K-, L and M-shell of the ions. To compare with theory, an elaborate theoretical model has been applied. By considering the relativistic atomic structure of Pb$^{81+}$, this model is based on a sophisticated computation of the initial population distribution via RR for all atomic levels up to Rydberg states with principal quantum number $n=$ 165 in combination with cascade calculations based on time-dependent rate equations. Within the statistical accuracy, the experimental x-ray line emission is in very good agreement with the results of the theoretical model applied. Most notably, this comparison sheds light on the contribution of prompt and delayed X-ray emission (up to 70 ns) to the observed X-ray spectra, originating in particular from Yrast transitions into inner shells. ISSN 2469-9934 not unique: **2 hits**. Supported by ERC under grant agreement # 6544002. Supported by BMBF under grant # 5P19SJFAA and 05P19RGFA1. ; PUB:(DE-HGF)16, ; 0, ; Atomic Physics (physics.atom-ph) FOS: Physical sciences WOS:000798848000011 Journal Article 2022 GSI-2022-00567 2022 https://repository.gsi.de/record/246562 https://doi.org/10.1103/PhysRevA.105.052804 <Go to ISI>://WOS:000798848000011