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Title: Electrons at the monkey saddle: A multicritical Lifshitz point

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Journal Article: Publisher's Accepted Manuscript
Journal Name:
Physical Review B
Additional Journal Information:
Journal Volume: 95; Journal Issue: 3; Related Information: CHORUS Timestamp: 2017-01-24 16:47:56; Journal ID: ISSN 2469-9950
American Physical Society
Country of Publication:
United States

Citation Formats

Shtyk, A., Goldstein, G., and Chamon, C. Electrons at the monkey saddle: A multicritical Lifshitz point. United States: N. p., 2017. Web. doi:10.1103/PhysRevB.95.035137.
Shtyk, A., Goldstein, G., & Chamon, C. Electrons at the monkey saddle: A multicritical Lifshitz point. United States. doi:10.1103/PhysRevB.95.035137.
Shtyk, A., Goldstein, G., and Chamon, C. Mon . "Electrons at the monkey saddle: A multicritical Lifshitz point". United States. doi:10.1103/PhysRevB.95.035137.
title = {Electrons at the monkey saddle: A multicritical Lifshitz point},
author = {Shtyk, A. and Goldstein, G. and Chamon, C.},
abstractNote = {},
doi = {10.1103/PhysRevB.95.035137},
journal = {Physical Review B},
number = 3,
volume = 95,
place = {United States},
year = {Mon Jan 23 00:00:00 EST 2017},
month = {Mon Jan 23 00:00:00 EST 2017}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1103/PhysRevB.95.035137

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Cited by: 1work
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  • We have studied H/sup +/+He ionizing collisions, and find that electrons stranded between the two postcollision Coulomb centers dominate the ejected-electron spectra for intermediate (--100 keV) projectile energies. The importance of these electrons is clearly established by our classical calculations which are in qualitative agreement, in both shape and magnitude, with experimental spectra taken by us, and with earlier measurements. These ''saddle-point'' electrons are produced by a classically understandable mechanism, and are unambiguously observed at nonzero scattering angles.
  • The continuum-distorted-wave eikonal initial-state (CDWEIS) model is used to study the ionization of hydrogen by protons of energy 10--500 keV. Ejected electron spectra are presented and discussed in the context of the saddle-point mechanism. The behavior of the ejected electron spectrum as the charge of the incident projectile is varied is also considered. It is concluded that within its range of validity, CDWEIS does not provide any evidence of the existence of saddle-point electrons.
  • The production of the saddle-point electrons in slow H+H{sup +} collisions is discussed in the framework of the quantum adiabatic approach. An analytical expression for the angular distribution of the ejected electrons is obtained.
  • Ionization in H(1{ital s})+H{sup +} collisions is studied in the relative collision energy range 4.0--25.0 keV by classical trajectory simulations. Improved total ionization cross sections are reported for the collision energies 2.0--10.0 keV. A thorough study of the qualitative dynamics of ionization has been carried out, with emphasis placed on the distinction between direct-impact'' and saddle-point'' mechanisms. A precise criterion for classifying trajectories according to these mechanisms is given, and by analyzing the trajectories in a quasistatic molecular frame it is shown that the distinction is established early in the collision. The development of position and velocity-space correlations in ensemblesmore » of trajectories of each type is studied.« less
  • Experimental and theoretical velocity distributions of electrons ejected in 1--6 keV ionizing H[sup +-]H collisions are presented. Both the experimental velocity distributions and the relative total ionization cross sections can be explained by the theory in a fully consistent way. Strong evidence is found for the existence of a saddle point ionization mechanism at collision energies of 4 keV and higher.