Photoionization of Ba⁺ions due to creation of 4d hole states

Abstract

Photoion spectrometry has been applied to determine the relative photoionization yields of Ba+ ions around the 4d ionization threshold. A ground state Ba+ ion beam was merged with monochromatized synchrotron radiation over a length of 15 cm. Counting the number of doubly and triply charged ions produced in the interaction region, we have obtained partial photoion yields as a function of photon energy. Prominent peaks due to resonance Auger processes have been observed below the threshold. A giant resonance structure above 4d threshold was seen only for the Ba3+ spectrum.

Absolute cross sections for the photoionization of 4d electrons in Xe+and Xe2+ions

“…The yield of Xe 2+ originates primarily from direct ionization of the outer 5p electrons and subsequent Auger decay is not possible. An analogous case exists for Ba + as discussed by Koizumi et al [24]. The cross section reaches much larger values in the region for the 4d → 5p transitions near 55 eV where three resonances appear (see figure 2).…”

Absolute Measurements and Theoretical Calculations of Photoionization Cross Sections along the Isonuclear Sequence of Multiply Charged Barium Ions

“…Previous photoabsorption experiments on Ba, Ba 1 , and Ba 21 [12,13] Ba 1 is similar to that of Ba while the absorption spectrum of Ba 21 is completely different [12], revealing a significant increase of the 4d-oscillator strength for discrete transitions. Among several theoretical approximations [14][15][16][17][18][19][20] proposed to interpret the Ba 21 spectrum multiconfiguration Hartree-Fock calculations [15,16,19] have yielded the best agreement with the experimental results.…”

“…Previous photoabsorption experiments on Ba, Ba 1 , and Ba 21 [12,13] found that the absorption of 273002-1 0031-9007͞01͞ 87(27)͞273002(4)$15.00…”

Investigation of the cascades in atoms using the global characteristics of spectra

“…The charge state and photoion spectra were studied for Ne [3,49], Ar [4,11,12,[50][51][52][53], Kr [5,6,33,[53][54][55][56], Xe [6,9,16,34,35,46,[57][58][59][60], and for all of them [61][62][63]. Also such spectra were investigated for lanthanides [7-9, 15, 32, 64-66], Mg [50,67], Al, Si, S, Ca, Fe [50], Cu [18], Sr [68], Ba [69], Au [70], Re [71], and Ta [71]. In [36] the ion charge distribution due to vacancy cascades following the K, L 1 , L 2 , and L 3 shell ionization were calculated by the Monte Carlo method for the atomic numbers Z = 10−60.…”