Double K-shell vacancy production in Ca, Ti, V and Cr bombarded by protons

Cindro, V.; Budnar, M.; Kregar, M.; Ramšak, V.; Šmit, Ž.

doi:10.1088/0953-4075/22/13/020

Cited by 18 publications

(10 citation statements)

References 39 publications

(24 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Furthermore, although electron and heavy-ion bombardment are known to cause multiple ionization, i.e. simultaneous outer-shell and K-shell ionization [1][2][3][4][5][6][7][8][9][10][11][12], yet these are not the only causes of multiple ionization as is evident from what follows. The x-ray lines arising out of the multiply ionized atoms are termed K satellite (KL n ) and K hypersatellite lines (K 2 L n ), where K m L n denotes the vacancy configuration of the initial state of the x-ray transition.…”

Section: Introductionmentioning

confidence: 99%

A study of radiative Auger emission, satellites and hypersatellites in photon-induced K x-ray spectra of some elements in the range 20⩽Z⩽32

Verma

2000

J. Phys. B: At. Mol. Opt. Phys.

View full text Add to dashboard Cite

Photon-induced K x-ray spectra of Ca, Ti, Fe, Zn and Ge have been investigated. The measurements have been made using a crystal spectrometer combined with a thin scintillation detector. Excited by the collimated photon beam from an Rh-anode x-ray tube, the spectra of all these elements reveal the existence of radiative Auger emission (RAE) structure and the satellite and hypersatellite lines along with the diagram lines. The energies and intensities of the Kα 2 , Kα 1 , Kβ 1,3 and Kβ 5 diagram lines and the Kα satellites and hypersatellite transitions are presented. The intensity of the RAE structure corresponding to the Kβ 1,3 x-ray transition and the energy of the RAE edge for each element is also reported. The measured results have been compared with the values from other sources such as electron/heavy-ion excitation and theoretical values. From the intensities of the satellite lines of these elements, the average L-vacancy fraction P L has been deduced in each case.

show abstract

Section: Introductionmentioning

confidence: 99%

A study of radiative Auger emission, satellites and hypersatellites in photon-induced K x-ray spectra of some elements in the range 20⩽Z⩽32

Verma

2000

J. Phys. B: At. Mol. Opt. Phys.

View full text Add to dashboard Cite

show abstract

“…The shift which was observed for the four investigated collisions might indicate that the yields of higer-order K␤ satellites, which are overlapping the K␣ hypersatellites were underestimated in our analysis. In the Mg spectra the K␤L 4 and K␤L 5 satellites are completely hidden by the stronger K␣ hypersatellites and their yields are practically undetermined in the measured spectra. By adjusting these two K␤ satellite yields so that the KL N and K 2 L N initial-state production yield distributions would match, an approximately 25% decrease in the overall double-K-shell vacancy production yield was obtained.…”

Section: Resultsmentioning

confidence: 95%

“…Hypersatellites have been resolved in these works, but due to the high probability of additional ionization in outer shells, resulting in complex x-ray spectra, hypersatellite intensities could not be determined accurately. In experiments with protons, however, where additional outer shell ionization is less probable, double-ionization cross sections for some low-Z elements could be obtained [4]. The same is true for heavy ions on mid-Z atoms [5], where additional outer-shell ionization was also negligible.…”

Section: Introductionmentioning

confidence: 90%

“…Since we are interested in photon yields, K␣ transitions are also shown, regardless of their probability. Figure 1 demonstrates that atomic states K 2 L 3 a contribute not only to the 4 a, and K␣L 4 c photon yields. Using the decay schemes of all excited states, the relation between the measured photon yields and the initial vacancystate production yields can be expressed in the following matrix form:…”

Section: B Decay Schemesmentioning

confidence: 98%

See 1 more Smart Citation

Double-K-shell ionization of Mg and Si induced in collisions with C and Ne ions

et al. 2004

View full text Add to dashboard Cite

The satellite and hypersatellite K x-ray emission of a thin Mg foil and thick polycrystalline Si target bombarded by 34-MeV C and 50-MeV Ne ions was measured using high-resolution crystal diffractometry. The corresponding projectile reduced velocities v / v K were 1.09 and 0.92 for C ions and 1.02, 0.86 for Ne ions in case of Mg and Si targets, respectively. An energy resolution of approximately 0.5 eV enabled separation of contributions corresponding to states with different numbers of K-and L-shell vacancies. The relative intensities of satellite and hypersatellite lines were determined by fitting the measured spectra with line shapes calculated using the GRASP92 computer code. To determine the production yields of initial states from the measured x-ray yields, the total decay schemes of initial states were considered. The decay schemes were also used to determine the relative intensities of components contributing to the observed K␣ satellites and hypersatellites and K␤ satellite intensities. Including theoretical predictions in the fitted model is crucial to analyze properly the K␣ hypersatellite region which overlaps the K␤ satellites. The initial-state production yields were then used to determine the L-shell ionization probabilities and the double-to single-K-shell ionization ratio corresponding to the four investigated collisions. The experimental values were compared to the theoretical predictions obtained within the independent electron model using single-electron ionization probabilities calculated by the three-body classical trajectory Monte Carlo (CTMC) method. Since the targets used were thick enough, the equilibrium projectile charge-state distributions in the solid media were assumed. While for the double-to single-K-shell ionization ratios a satisfactory agreement was observed between the CTMC predictions and our experimental results, the L-shell ionization probabilities were found to be overestimated by the CTMC calculations by a factor of about 2.

show abstract

“…Aside from the high energy resolution, the Ti spectral region between both diagram lines demonstrates the high sensitivity of the setup. Despite a very low ionization cross section ( σ KK / σ K ∼ 10 −3 ) a Kα h hypersatellite contribution corresponding to the radiative decay of a doubly 1s ionized atom 26 is clearly observed, as well as a weak K-MM radiative Auger spectral contribution 27 on the low energy tail of the Ti Kβ diagram line.…”

Section: Resultsmentioning

confidence: 96%