Electron-Impact Excitation of Pb+

Excitation of the 6d 2D → 6p 2Po Radiative Transitions in the Pb+ Ion by Electron Impact

“…Energy dependences of the emission cross-sections for the λ143.4 nm (red color) and λ182.2 nm (blue color) spectral lines (circles-experiment; dash curves-our calculation; dot-dash curve-calculation [16]).…”

“…Table 1. Cross-sections σ (•10 -16 cm 2 ) for the transitions between the 6s 2 6p 2 P o and 6s 2 6d 2 D levels at 100 eV ( a -our calculation; b -calculation [16]; c -the value obtained from the experimentally observed ratio of the line intensities 1.8). The relationship between emission (σ em ) and excitation (σ ex ) cross-sections is σ em = BR•σ ex (BR-the branching ratio).…”

“…For comparison, the result of the calculation [16] for the excitation cross-section of the 6s 2 6p 2 P o 1/2 → 6s 2 6d 2 D 3/2 transition (when taking into account the branching ratio of 0.8) is also presented in Figure 1 by dot dash red curve. Note that the calculation [16] does not incorporate the effects of cascade transitions and the resonance contribution of autoionizing states. As it is seen from Figure 1, the behavior of both curves is similar in the energy range 25-100 eV.…”

“…For the ions of group III, there are experimental investigations of the electron excitation of the Ga + [9], In + [10,11], and Tl + [12] ions as well as theoretical calculations of the excitation cross-sections for the Al + [13] and In + [14] ions. As for the data on electron-impact excitation of the metal ions of group IV, they are very poor, and are presented, to our knowledge, with only one experimental [15] and one theoretical [16] study for the electron-impact excitation of singly charged lead. The radiation constants for this ion are of great interest in recent years since spectral lines of the Pb + ion have been detected in several stars, including Ap and Am stars, as well as in the interstellar medium [17,18].…”

“…So far, FAC is the convenient tool for constructing high-quality wave functions of electron scattering on atoms and ions and has proven to be good for the analysis of energy levels, Auger cascades, electron-impact excitation, and ionization cross-sections [20][21][22]. Likewise, in the GRASP2k package used in the calculation [16], FAC also incorporates a core-valence correlation, configuration mixing, and relativistic effects, which are very important to account for in the case of such a heavy ion as singly charged lead.…”