Year: 1989
Type: article
Abstract: Multiple photoionisation processes of Cs and Ba atoms due to creation of 4d hole states have been studied by measurement of photoion-yield spectra (energy dependence of photoion yield). Monochromatised synchrotron radiation was used to excite the 4d-shell electron, and measurements were made in the energy regions from the neighbourhood of the 4d-nl resonance excitation to the higher-energy tail of the big 4d- in f shape resonance. The main products in these regions are doubly-charged (Cs 2+ , Ba 2+ ) and triply-charged (Cs 3+ , Ba 3+ ) ions, and an appreciable number of Cs 4+ and Ba 4+ ions starts being produced around the lowest photoelectron shake-off (4d -1 nl -1 ) and shake-up (4d -1 nl -1 n ' l ' ) states, respectively. Although the relaxation of the 4d hole states proceeds mainly through stepwise processes consisting of the normal Auger process and autoionisation, Auger shake-off processes are found to have considerable probabilities (typically 0.19-0.38 in the case of Cs) in the first stage of the relaxation. The shake-off probability associated with the 4d photoionisation in Cs estimated from the present data amounts to 0.33+or-0.05 in the region of the higher-energy tail of the shape resonance.
Authors: T Nagata, Y Itoh, T Hayaishi, Y Itikawa, T Koizumi, T Matsuo, Y Sato, E Shigemasa, A Yagishita, M Yoshino
Institution: High Energy Accelerator Research Organization
Language: English
Topic: Atomic and Molecular Physics
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W2000896933