Interference Effect in Electron Emission in Heavy Ion Collisions withH2Detected by Comparison with the Measured Electron Spectrum from Atomic Hydrogen

Abstract

Direct evidence of the interference effect in the electron emission spectra from ionization of molecular hydrogen in collisions with bare C and F ions at relatively low collision energies is presented. Oscillations due to the interference are deduced by comparing the measured double differential cross sections of the electrons emitted from molecular hydrogen to those emitted from atomic hydrogen, rather than using the calculated cross sections for H as in a previous report. We believe these experimental data provide stronger support for the evidence of the interference effect. We show that it is not only a feature of very high energy collisions, but also a feature to be observed in relatively lower energy collisions.

Angle-differential observation of plasmon electrons in the double-differential cross-section spectra of fast-ion-induced electron ejection fromC60

“…As shown above, the collective excitation peak corresponds to almost 50% of the total ionization process; this may also imply that the collective excitation and similar many-body effects which are responsible for a large amount of electron emission at low energy must be considered for modeling any practical application, such as heavy-ion-induced radiation damage of the biological cells or DNA bases, or nanoparticles [39]. The decay of collective plasmon excitations in fullerene thus provides a mechanism to enhance the low-energy electrons which is consistent with that predicted, very recently, in other carbon-based nanosystems [39].…”

“…In addition, the ejected electron spectrum is largely dominated by the single-particle Coulomb-ionization mechanism, where the cross section falls over several orders of magnitude in the emitted electron energy range, i.e., typically over 1-300 eV. This makes the observation of the secondary features in the electron spectrum even more challenging, which has already been demonstrated in the recent series of the study of the Young-type electron interference effect in ionization of H 2 [38,39] in heavy-ion impact. Nevertheless, the direct electron emission being the fastest mode of the deexcitation of the collective state GDPR [16] makes this study even more interesting.…”

Periodic Variations in the Wavelength Distributions following Photon Interferences: Analogy with Electron Interferences

“…During the last years, electron interference effects have been widely investigated in electron-and ion-induced ionization [7][8][9][10][11][12][13][14][15][16][17][18], as well as in photoionization [19][20][21][22][23][24][25][26][27] of isolated atoms and molecules. In the electron interference experiments [5][6][7][8][9][10][11][12][13][14][15][19][20][21][22][23], each single electron hits the position-sensitive detector like a particle but traverses the interferometer slits (or scatters on atomic centers) like a wave. Thus, over many repetitions, an interference pattern builds up as oscillations of the intensity I(θ d ) = (dI/dλ)dλ with the observation angle θ d [5][6][7][8][9][10].…”

Direct observation of Young’s double-slit interferences in vibrationally resolved photoionization of diatomic molecules

“…However, due to the rapid decrease of σ 0 with photoelectron energy, i.e., with k e , the oscillations are usually hidden and must be uncovered through dividing the total cross section by an independent but arbitrary estimate of σ 0 , leading to equivocal interpretations (18,19). This difficulty has been so far circumvented by considering the ratio of two rapidly decreasing cross sections associated with different molecular ionization channels [e.g., the g/u ratio resulting from K-shell photoionization of N 2 (11,25)].…”

“…Over the last few years, a substantial experimental effort has been devoted to investigate these two-center interferences in the simplest diatomic molecules, mainly in the context of photoionization [see, e.g., (7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)], but also in ionizing collisions with fast ions (18)(19)(20)(21) and electrons (22)(23)(24). However, due to the rapid decrease of σ 0 with photoelectron energy, i.e., with k e , the oscillations are usually hidden and must be uncovered through dividing the total cross section by an independent but arbitrary estimate of σ 0 , leading to equivocal interpretations (18,19).…”