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10Complex Systems of Charged Particles and their Interactions with Electromagnetic Radiation 2019
DOUBLE IONIZATION AND SATELLITE EXCITATION IN SOFT AND
HARD X-RAY REGIONS
V.G. Yarzhemsky12, M.Ya. Amusia3,4
1Kurnakov Institute of General and Inorganic Chemistry of the Russian Academy of Sciences,
Moscow, Russia, e-mail [email protected] 2Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region, Russia Racah Institute of Physics, the Hebrew University, Jerusalem, Israel, e-mail: [email protected] 4Ioffe Physical-Technical Institute, St Petersburg, Russia
Theoretical photionization cross-sections in a Hartree-Fock approximation are often used for estimation of line intensities in photoelectron spectra. On the other hand, according to experimental results about 8-10 % of the main line intensity are transferred to shake-up satellite excitation and total intensities of shake-up and shake-of satellites are about 20% of the main line [1]. Hence it follows that account for many-electron effects is important in photoelectron spectroscopy. Theoretical approaches to the double ionization are usually based on the perturbation theory, where the potential of a hole initially created by the photon is considered as a perturbation potential
In the lowest order of the many-body perturbation theory the relaxation of the core hole k, created in photoionization, is described by its transition to double-hole-one-particle states i-1j-1s. The spectral distribution is given by the spectral function of initial hole:
A (E) = 1_Im Zk(E)_ (1)
k n(E -sk -Zk (E))2 +(Im Zk (E))2
Where the self-energy Zk (E) is given by its real and imaginary part by the formula:
Re Zk (E) = £ S"1} . Im Zk (E) = n( kj |U| is)2 s( E - s, - s} + Ss) (2)
ijs E Si Sj + Ss
Here are the Coulomb matrix elements of inter-electron interaction, and the sum (integral)
runs over all final states i-1j-1s including the discrete and continuum excited states s. The main line intensities for all atoms calculated by formulas (1) and (2) are in agreement with experimental data [1].
In the present work calculation were performed for satellite excitations from valence and core shells of noble gases. The lineshapes of low-energy Auger decay are calculated and compared with experimental data. In is shown that in the hard x-ray energy region, where satellite excitation from core holes are possible the photoinization cross-section should be modified to take into account energy transfer to satellites.
The work was carried out within the State Assignment on Fundamental Research to the Kurnakov Institute of General and Inorganic Chemistry
References
[1] MP. Seah, I S. Gilmore. Phys. Rev. B 73, 174113.
[2] V.G. Yarzhemsky, M.Ya. Amusia. 2016 Phys. Rev. A 93 063406.
[3] V.G.Yarzhemsky, M.Ya.Amusia, et.al. 2010 J.Phys.B:Atomic Molec Opt. Phys. 43 185204.
