Excitation Cross Sections of YII Singlet Levels during e–Y Collisions

The excitation of singlet levels of a singly charged yttrium ion during collisions of slow electrons against yttrium atoms is investigated experimentally. At the electron energy of 50 eV, the excitation cross sections of YII 32 spectral lines of YII are measured; the electron energy dependence of the cross sections is registered in the energy range of 0–200 eV for 30 of them. Based on the obtained data, the total excitation cross sections of 11 energy levels are calculated, as well as the contribution by cascade excitation for seven levels. Absolute values of the excitation cross sections of even and odd levels differ by less than one order of magnitude.     

Excitation of PtI Transitions Terminating on Singlet Levels

The method of extended crossing beams is used to investigate the excitation of platinum atom transitions terminating on singlet levels. Thirty eight excitation cross sections are measured at the electron energy of 30 eV; nine optical excitation functions are recorded in the electron energy range from zero to 200 eV. Also measured are eight excitation cross sections of transitions which have even upper levels. Possible excitation channels are discussed, which define the absolute values of cross sections and the form of optical excitation functions.__________Translated from Teplofizika Vysokikh Temperatur, Vol. 43, No. 4, 2005, pp. 510–515.Original Russian Text Copyright © 2005 by Yu. M. Smirnov.     

Electron impact excitation cross sections of tungsten atom

An experimental study is made of excitation of tungsten atom by electron impact at the energy of exciting electrons of 50 eV. The values of total excitation cross sections for 40 energy levels of WI are determined. The largest cross section of 2.06 × 10^?16 cm² corresponds to the odd level of 43 975 cm^?1 with J = 2.     

Excitation of Triplet and Septet Levels of MnII during Electron–Atom Collisions

The excitation of triplet and septet levels of a singly charged manganese ion during collisions of electrons with manganese atoms is investigated using the method of extended crossed beams. At the electron energy of 50 eV, 26 excitation cross sections are measured, and 11 optical excitation functions are registered in the range of electron energies from zero to 200 eV. Possible channels of excitation of the triplet and septet levels of MnII are discussed. The obtained results are compared with the data of previous experiments.     

Excitation of Even Triplet Levels of LaII in e-La Collisions

The excitation of radiative transitions from even triplet levels of LaII is investigated by the method of extended crossing beams with detection of optical signal from the region of crossing. The optical excitation functions are measured for 27 spectral lines in the electron energy range of 0–200 eV. Based on the results of measurements, the total excitation cross sections are calculated for 34 energy levels of a singly charged lanthanum ion at the electron energy of 30 eV.     

Dissociative excitation of selenium atoms in collisions of electrons with Se2 molecules

The dissociative excitation of selenium atom by electron impact is investigated for the first time under conditions of narrow composition of molecular beam. The thermal destruction of heavy Se_n molecules is used to obtain a beam with prevailing Se₂ molecule. Seventeen cross sections of dissociative excitation of SeI are measured at electron energy of 50 eV. Possible reactions of formation of excited selenium atoms in e-Se₂ collisions are discussed.     

Excitation of Resonance Transitions of Neodymium Atom in Ultraviolet in e–Nd Collisions

The excitation of resonance transitions of neodymium atoms in ultraviolet is investigated using the method of extended crossing beams. The majority of the measured cross sections lie in the range from 10^–17 to 10^–18 cm². Thirty-one optical excitation functions are registered upon variation of the electron energy from the excitation threshold to 200 eV. For 39 transitions, a classification within the framework of the known system of terms is suggested.     

Excitation of transitions of singly charged ytterbium ions terminating on levels 4 f 13(2 F °7/2)5 d 6 s (3 D ) 3[ L 2]°

The excitation of transitions of singly charged ytterbium ions terminating on odd levels 4f ¹³(² F°_7/2)5d6s(³ D) ³[L ₂]° is experimentally studied. The generation of excited ytterbium ions occurs as the process of simultaneous excitation and ionization under single electron-atom collisions. Eighty five excitation cross sections are measured at an electron energy of 50 eV. Fifteen optical excitation functions are recorded with the energy of exciting electrons varying from zero to 200 eV. Original Russian Text ? Yu.M. Smirnov, 2008, published in Teplofizika Vysokikh Temperatur, Vol. 46, No. 2, 2008, pp. 197–205.     

Cross Sections of Excitation of Resonance Transitions of EuI by Electron Impact

The excitation of resonance transitions of a europium atom by electron impact is investigated using the method of extended crossing beams. Comparison of the obtained results with data of previous investigations shows that the form of the optical excitation functions is in good agreement with the experimental data but differs considerably from the theoretical ones. The absolute values of cross sections at the electron energy of 100 eV are close to predicted values and exceed the data of the previous experiment by two orders of magnitude.     

Excitation of 6S0, 6P0, and 6D0Levels of Niobium Atom by Electron Impact

The excitation of odd sextet levels of the niobium atom in collisions with slow electrons is investigated experimentally. The measured values of the excitation cross sections of the spectral lines of NbI are used to determine the excitation cross sections of energy levels. The available reference data on the branching factors are used for more complete inclusion of branching. The obtained values of excitation cross sections of the levels of the niobium atom are compared with the theoretical values.