Two-photon decay of K-shell vacancy states in heavy atoms

摘要: Abstract Two-photon decay has been extensively studied in atomic, nuclear and particle physics since the 1930s when problem of stability 2s state hydrogen atom emerged. Since then, many theoretical experimental investigations have made on one-electron (H-like) ions helium two-electron (He-like) ions. The work two-photon many-electron systems involving inner shells started about 30 years ago and, meantime, K-shell vacancy subject studies. Experimental results obtained for 2 s → 1 higher-state electron transitions molybdenum, 1s, 3s 3d 1s 4sd silver, xenon, hafnium mercury. Nonrelativistic relativistic calculations processes made. silver xenon atoms are a reasonable agreement with results, but some problems remain to be solved. A review atomic is presented.