K X-ray satellite structures of bromine and molybdenum

The energies and electric dipole rates of Kα X-ray satellites due to 1s-2p transitions in bromine and molybdenum with one to five vacancies in the 2p shell and other shells retaining their normal occupation numbers are computed using Multi-Configuration Dirac Fock wavefunctions with the inclusion of relativistic and quantum electrodynamic corrections. As fully relativistic calculations on all the Kα X-ray fine structure satellites with multiple spectator vacancies in the 2p shell of elements under consideration, to the best of our knowledge, are reported in this work for the first time, the accuracy of the E1 data is analyzed in terms of the agreement between the rates in the length and velocity forms. While the intensities of the strong electric dipole lines in the various groups of 1s - 2p transitions obey the well established Z dependence, many of the weak transitions vary randomly with Z and an attempt is made in this work to understand the behaviour of the spin-forbidden and weak electric dipole lines in the KαL ⁿ X-ray satellite structure of Br, Mo, I, and Au. As the number of closely spaced fine structure transitions range from a few to many depending on the spectator vacancies in the 2p shell, the intensity weighed statistical average satellite energies, line strengths and photo-ionization cross sections are reported to guide in the reliable interpretation of experimental measurements.     

Origin of the satellite Kβ10 in X-ray spectra

The transition energies corresponding to the transition array KM_x→M_xM_2,3 (x = 1, 2, 3, 4, 5) have been calculated using Slater formulas for interaction between two holes in inner shells and HFS values of electrostatic Slater integrals. The initial and final state energies have been corrected for the adiabatic relaxation of atomic orbits, which take place due to creation of an inner vacancy. The value of this adiabatic relaxation energy for KM states has been calculated semi-empirically by comparing the KM₁³S₁→L₃M₁³P₂ transition energies with the measured Kα₁ line energies. For the final state, this value has been taken from available literature[21]. It is found that the satellite β₁₀ in the K-emission spectra of Zn, Ga, Ge, Mo and Rh is emitted by the superposition of more than one transition of the array. Consideration of the relative transition probabilities shows that the major contribution to β₁₀ comes from a K→M_2,3 transition in the presence of a 3d spectator vacancy. It has been suggested that the satellite β′₁ (7655.5 eV, Edamoto 1950) in the K-emission spectrum of cobalt, and the satellite β₇ (8271.2 eV) in the K-spectrum of nickel should be reidentified as β₁₀. It has been shown that the two lines β′₁ (8268.0 eV) and β″₁(8270.3 eV) observed[13] in the nickel Kβ spectrum are two components of the satellite β₁₀, and it is hence suggested that these should be renamed β₁₀⁽¹⁾ and β₁₀⁽²⁾ respectively. Similarly, the lines β″₍₁₎ (8909.3 eV) and β″₍₂₎(8913.0 eV) in the CuKβ spectrum are proved to be two components of β₁₀ and hence should be renamed β₁₀⁽¹⁾ and β₁₀⁽²⁾ respectively.     

Optical transitions in ZnS type crystals containing cobalt

The optical properties of ZnS crystals, ZnS and (Zn,Cd)S phosphors activated by cobalt were studied in the temperature range from 4.2°K to 300°K. The absorption bands with an energy of 1.75 and 0.85 eV split when the crystals are cooled. However, the absorption at 0.4 eV is more pronounced at 76°K than at the temperature of liquid helium. The infrared emission due to cobalt at 0.4 eV increases by cooling the crystal and shows some structure at low temperature. This emission can be excited by irradiation into the absorption bands at 1.75 and 0.85 eV.Additional irradiation by short wavelength light (2.5 eV ≦ E ≦ 3.2 eV) at low temperatures changes the absorption spectra and the emission spectra : (1) The characteristic excitation peaks of Co⁺ are reduced, whereas an additional absorption with a maximum at about 1.3 eV occurs. (2) The infrared emission due to Co⁺⁺ at 0.4 eV decreases, but a new emission within an energy range of 0.6 eV ≦ E ≦ 0.9 eV appears, generated in Cu⁺⁺ centres.The changes of optical properties by additional radiation and by cooling the crystals are explained by charge transfer processes Co⁺⁺ ⇄ Co⁺ and Cu⁺ ⇄ Cu⁺⁺.     

M-like X-ray transitions in superheavy quasi-molecules

The anisotropy of the molecular orbital X-ray emitted in heavy-ion collisions was investigated for 18 systems with combined atomic numbers between 104 and 184. Well defined anisotropy peaks were observed which may reflect M-like transitions in the corresponding superheavy two-center molecules.     

Dirac-Hartree-Fock studies of X-ray transitions in meitnerium

The K -shell and L -shell ionizations potentials for ²⁶⁸ ₁₀₉Mt were calculated at the Dirac-Hartree-Fock level taking into account quantum electrodynamic and finite nuclear-size effects. The K _α1 transition energies for different ionization states are accurately predicted and compared with recent experiments in the α -decay of ²⁷² ₁₁₁Rg .     

X-ray photoelectron spectra of cobalt compounds

The X-ray photoelectron spectra of a variety of cobalt(II) and cobalt(III) complexes have been investigated. Intense satellite lines were observed for the 2p, 3s and 3p peaks in the case of the high spin cobalt(II) compounds, but not for low spin cobalt(III) complexes. The satellites of the 2p levels are best explained as arising from shake-up processes, whereas those of the 3s and 3p levels are thought to arise largely from multiplet (exchange) splitting of the levels. Multiplet splitting of the 2p level is small and responsible for an increase in the doublet separation of the 2p_1/2, 2p_3/2 spin-orbit levels of the high spin cobalt(II) compounds. The chemical shifts for cobalt differ for the 2p, 3s and 3p levels of the high spin cobalt(II) compounds. Those of the 2p and 3p levels of diamagnetic cobalt(III) and low spin cobalt(II) complexes are equal. The difference in the case of the high spin cobalt(II) compounds is thought to be due to the presence of unpaired 3d electrons.     

X-ray transitions from antiprotonic noble gases

The onset of antiprotonic X-ray transitions at high principal quantum numbers and the occurrence of electronic X-rays in antiprotonic argon, krypton, and xenon has been analyzed with the help of Multiconfiguration Dirac-Fock calculations. The shell-by-shell ionisation by Auger electron emission, characterised by appearance and disappearance of X-ray lines, is followed through the antiprotonic cascade by considering transition and binding energies of both the antiproton and the remaining electrons. Electronic lines could be attributed partly to specific states of the antiprotonic atom de-excitation.     

X-ray absorption spectra of cobalt in ferromagnetic borides

The K x-ray absorption spectra of cobalt in the borides, the oxide, and in the pure metal are compared with the magnetic properties. The intensity of the initial absorption region decreases essentially linearly with the transition to higher borides, because of the progressive filling of d-like vacancies in the valence band of the metal by valence sp electrons of boron.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii Fizika, No. 1, pp. 24–28, January, 1970.     

K −-Proton atomic transitions

The relation between theK ^}-P scattering length and the X-ray spectrum for the 2p → 1s electromagnetic transition inK ^?-P atoms is examined. A coupled-channel potential model is used to explicitly calculate the energy of theS-matrix pole in the 1s channel, which is then compared with the energy obtained from the scattering lengths via the standard equation. The X-ray spectrum is calculated and compared with the Lorentzian shape associated with the complex energy of theS-matrix pole. In addition, theK ^?p branching ratios are compared at threshold and at the complexS-matrix pole energy.     

Pionic and muonic X-ray transitions in liquid helium

Energies and intensities of pionic and muonic X-rays in liquid ⁴He have been measured with a Si (Li) detector. The energy shift due to strong interaction effects of the pionic 1s level in ⁴He was determined to be ?75.7±2.0 eV. The natural line width of this level is 45±3 eV. These values are compared with different theoretical predictions. Cascade calculations, including external Auger effect and sliding transitions, have been performed to reproduce the yields of the muonic and pionic transitions. The pionic 2p level width is deduced: $\text{Γ}{}_{\mathrm{<mtext>2</mtext><mtext>p</mtext>}}\text{= (1.1 ± 0.5) × 10}{}^{12}\text{sec}{}^{\mathrm{?1}}\text{=}\text{(7.2±3.3) × 10}{}^{\mathrm{?4}}\text{eV}$.     

X-ray transitions in hydrogen-like,helium-like and lithium-like boron

The boron K X-ray spectra produced in heavy ion collisions using gas targets are reported. The observed X-ray transitions are used, to identify the one, two and three electron series of boron. The observed X-ray transition energies are found to agree well with theoretical calculations. A relatively large number of transitions involving double K-shell vacancies are observed. These transitions represent the first observation of double K-shell vacancies produced in collisions where the inner shell vacancies occur from electron promotion via molecular orbitals of the quasi-molecule formed during the collision.     

K conversion coefficients of transitions in87Sr

TheK conversion coefficients of the 388 and 483 keV transitions in⁸⁷Sr populated in the decay of⁸⁷Y have been measured with Ge(Li) and Si(Li) detectors by the NPG method. We find α _K values of 0.162 ± 0.010 and 0.00260 ± 0.00013 for the 388 and 483 keV transitions, respectively.     

Screening doublet law and X-ray satellite spectra

1. 1.
   A critical examination of the existing data on X-ray satellite spectra has led to a fuller information regarding the occurrence of pairs of satellite lines in theK, L andM regions, showing more or less constant value ofΔ√ν/R, similar to the screening doublets in the X-ray energy levels of singly ionised atoms.     
   
   

Nuclear charge radii from muonic X-ray transitions in F,Na, Al,Si, P,S and K

Energies of muonic X-rays of the Lyman series of seven light natural elements (F, Na, Al, Si, P, S and K) have been determined with an accuracy of between 15 and 30 eV. Equivalent charge radii have been deduced. For μ^?-K, transitions to the 2s state allowed an additional constraint on the Fermi c-t diagram. The results are in good agreement with, and generally of an order of magnitude higher precision than, comparable electron scattering data.     

Distinction between weak Auger transitions and internal X-ray photoemission

Estimates of the relative intensities of KLV Auger electrons and internally excited photoelectrons of similar energy show that the Auger process will dominate contrary to a recent suggestion by Powell.