Penningionization processes involving cold Rydberg alkali metal atoms Alaa Abo Zalam, Milan S. Dimitrijević, Vladimir A. Srećković, Nikolai N. Bezuglov, Kaspars Miculis, Andrey N. Klyucharev and Aigars Ekers Eur. Phys. J. D, 74 12 (2020) 237 Published online: 03 December 2020 DOI: 10.1140/epjd/e2020-10507-7