The doubly inelastic contribution to electron loss: H0and He0(0.5 MeV u-1) in collision with Ar

Kuzel, M.; Heil, O.; Maier, Robert R. J.; Lucas, M W; Jakubaßa-Amundsen, Doris H.; Farmery, B. W.; Groeneveld, K. O.

doi:10.1088/0953-4075/25/8/017

Cited by 14 publications

(27 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Somewhat surprisingly, subsequent measurements of doubly differential electron loss cross sections from hydrogen or helium impact on all rare gases up to Kr [12][13][14] did not reveal any Ramsauer-Townsend effects on the electron loss peak itself. Both peak position and peak width were found to depend smoothly on the ejection angle within the experimental errors, thereby throwing some doubt on any theory derived from free electron scattering.…”

Section: Ramsauer-townsend Effect In the Electron Loss From H° Collidmentioning

confidence: 90%

“…The emitted electrons were analyzed with an electrostatic cylindrical mirror spectrometer [14] which could be rotated under vacuum to accept emission angles Of in the range O°<0/<63°, 90°, and 117° < 0/< 180°. The energy and angular resolution were AE/E =3.14% and A0 = 1.67°.…”

Section: Ramsauer-townsend Effect In the Electron Loss From H° Collidmentioning

confidence: 99%

“…The energy and angular resolution were AE/E =3.14% and A0 = 1.67°. Absolute yields were obtained by means of normalizing to the Rudd, Toburen, and Stolterfoht data [16] as described in the previous work [14]. The uncertainty of the absolute yields is about 80%, while the relative yields are accurate within at most 20%.…”

Section: Ramsauer-townsend Effect In the Electron Loss From H° Collidmentioning

confidence: 99%

“…This made it difficult to extract the precise peak shape for backward emission angles. Second, the backward hemisphere was only explored with He, Ne, and Ar targets [13][14][15] and at such high collision velocities that Ramsauer-Townsend effects are either absent (He, Ne) or rather weak (Ar). The heaviest target used so far for electron loss peak shape studies [12] was Kr, but only at emission angles below 20°, and at these forward angles the strong decrease of the electron loss peak intensity with angle veils any contingent structures in the doubly differential cross section.…”

mentioning

confidence: 99%

See 3 more Smart Citations

Ramsauer-Townsend effect in the electron loss fromH0colliding with heavy atoms

et al. 1993

View full text Add to dashboard Cite

The emission pattern of loosely bound projectile electrons is strongly dependent on the target species. For 0.5 MeV hydrogen colliding with krypton we observe large variations in the intensity of these electrons as a function of emission angle. There are also large changes in the energy and width of the electron loss peak associated with these intensity variations. These features are closely related to the Ramsauer-Townsend scattering of free electrons and can be interpreted within the electron impact approximation, a model which successfully combines free electron scattering by the heavy target with the Compton profile of the initially bound projectile electron.PACS numbers: 34.50.FaOne of the fundamental processes occurring in heavy ion collisions is the ejection of electrons. A study of their energy and angular distribution provides a unique insight into the collision dynamics and into the atomic structure of the collision partners [1]. With the availability of recent more accurate measurements one has a sensitive test of traditional theoretical models and those being newly developed. An essential feature in the spectrum arising from projectiles which carry electrons into the collision is in "the electron loss peak" which was independently discovered by Burch, Wieman, and Ingalls [2] and Wilson and Toburen [3] and identified to originate from these projectile electrons. Since the peak is located at an energy which approximately corresponds to the energy of the outermost projectile electron in the target rest frame, one of the earliest interpretations was based on the idea that electron loss might be treated as an elastic collision between the projectile electron and the target atom. Free electron-atom scattering (as reviewed by, e.g., Bransden and McDowell [4]) is a field which has been thoroughly investigated in order to get detailed information about the electronic properties of the target. As early as the 1920s, Ramsauer [5] and Townsend and Bailey [6] discovered pronounced structures in the energy dependence of the elastic scattering cross section from heavy rare gas atoms. Later investigations [7,8] have revealed that these intensity variations arise from deep minima in the angular dependent differential cross sections. These structures, which can be reproduced with the help of close-coupling calculations [9,10], have been interpreted in terms of interference effects between the different partial waves contributing to the scattering amplitude. The absence of structures for helium targets and the increase of the number of minima with increasingly heavier rare gases (at fixed impact energy) could then readily be explained by the number of partial waves required: only a few for He, but some tens for the heaviest gases.Menendez and Duncan [11] were the first to discover structures in the angular dependent singly differential cross section in the case of clothed ion impact. Somewhat surprisingly, subsequent measurements of doubly differential electron loss cross sections from hydrogen or helium impact on all ...

show abstract

Section: Ramsauer-townsend Effect In the Electron Loss From H° Collidmentioning

confidence: 90%

Section: Ramsauer-townsend Effect In the Electron Loss From H° Collidmentioning

confidence: 99%

Section: Ramsauer-townsend Effect In the Electron Loss From H° Collidmentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

Ramsauer-Townsend effect in the electron loss fromH0colliding with heavy atoms

et al. 1993

View full text Add to dashboard Cite

show abstract

“…These measurements were also mainly restricted to the extreme forward angles. Other than that, there are few measurements available which involve low-Z atoms as the projectile [46,47]. Therefore, because of a lack of systematic experimental data and proper theoretical calculations covering a wide energy and angular range, the influence of projectile electrons in the low-energy region is still to be understood in detail.…”

Section: Introductionmentioning

confidence: 99%

Electron emission in ionization of He and Ne by fast dressed oxygen ions and projectile-charge-state dependence

et al. 2015

View full text Add to dashboard Cite

The double-differential cross sections (DDCS) of low-energy electrons emitted at forward, backward, and perpendicular directions are reported for collisions of 3.75 MeV/u O q+ (q = 5, 6, 7, 8) projectiles with He and Ne targets. The measured DDCS are found to be deviating from the q 2 dependence throughout the entire energy region. The effect of projectile electrons, for the dressed ions, as a function of the impact parameter is clearly noticeable for large as well as low-impact parameter collisions. We also present a theoretical calculation based on the prior form of the continuum distorted wave-eikonal initial state approximation, in which the projectile-active electron interaction is modeled with the Green-Sellin-Zachor potential. This particular representation of the potential has been proven to give good qualitative results for projectiles with residual electrons. In addition to the total DDCS, the individual contributions from target ionization, projectile electron loss, and simultaneous ionization processes are also calculated. The total DDCS obtained from these calculations are shown to be in excellent agreement with the experimental observations.

show abstract