On the high-energy limits for the double-to-single ionization ratio of helium and helium-like ions in collisions with charged and neutral particles

One of the first exotic phenomena observed in the 80s of the last century was an event registered by a calorimetric type installation. In this event, an anomalous relationship was observed between charged and neutral hadrons, arising from the collision of a high-energy particle with a carbon nucleus. In accordance with the principle of isotopic invariance, the number of neutral pions should be equal to the number of charged pions. The event, which was recorded by Japanese physicists, contained only charged peonies with no neutral [1]. This event was named "Centaur". Until now, such events have not been observed in accelerator experiments. The article presents the results of searching for such events in experiments at the DESY HERA collider. For the candidates for Centaur events and for all other events, constructed distributions by the type of fitability of charged tracks in CTD. Since the absence of neutral particles in events is explained by methodological reasons, "Centaur" events were not detected in electron-proton interactions at the ZEUS facility.

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Measurements of the electron-impact double-to-single ionization ratio using trapped lithium

Physical Review A ◽

10.1103/physreva.66.012715 ◽

2002 ◽

Vol 66 (1) ◽

Cited By ~ 5

Author(s):

M.-T. Huang ◽

L. Zhang ◽

S. Hasegawa ◽

S. H. Southworth ◽

L. Young

Keyword(s):

Electron Impact ◽

Single Ionization ◽

Ionization Ratio

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The ratio of cross sections for double to single ionization of helium by high energy photons and charged particles

Journal of Physics B Atomic Molecular and Optical Physics ◽

10.1088/0953-4075/28/6/009 ◽

1995 ◽

Vol 28 (6) ◽

pp. 913-940 ◽

Cited By ~ 154

Author(s):

J H McGuire ◽

N Berrah ◽

R J Bartlett ◽

J A R Samson ◽

J A Tanis ◽

...

Keyword(s):

Cross Sections ◽

Charged Particles ◽

High Energy ◽

Single Ionization

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Multi Charged Ions in Accelerators

Advances in Theoretical & Computational Physics ◽

10.33140/atcp.01.01.07 ◽

2020 ◽

Vol 1 (1) ◽

Keyword(s):

Nuclear Physics ◽

Radiation Flux ◽

Experimental Studies ◽

High Energy ◽

Neutral Particles ◽

Wide Range ◽

A Charge ◽

Physics Experiments ◽

Charged Ions ◽

Positively Charged

We have presented the results of experimental studies of the characteristics of the products resulting from the expansion of plasmoids formed under laser irradiation at different wavelength: 0.69, 1.06 and 10.6µm. The radiation flux density was varied in a very wide range, which made it possible to obtain (different in intensity and energy) fluxes of charged and neutral particles. In this case, the positively charged ions have a charge from Z=1 to Z=30, which allows the use of laser plasma multi charged products in various nuclear physics experiments and super high energy accelerators [1].

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A sputter source for electron microscopic preparation

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100107897 ◽

1978 ◽

Vol 36 (1) ◽

pp. 150-151 ◽

Cited By ~ 1

Author(s):

E. Jakopić ◽

A. Brunegger ◽

R. Essl ◽

G. Windisch

Keyword(s):

Discharge Chamber ◽

High Energy ◽

Low Energy ◽

The Other ◽

Ion Current ◽

Electron Microscopic ◽

Neutral Particles ◽

Fine Grained ◽

Sputtering Yields

Coating electron microscopic specimens by sputtering yields particulary fine grained coatings of strong adherence. Two methods have been applied up to now. Their difference lies in the arrangement of target and specimen. If, in one case both, target and specimen are arranged inside the discharge chamber,damage by the discharge of sensitive specimens is possible (Fig.la). If, in the other case both, target and specimen are arranged outside the discharge chamber, focussing of the ions is necessary, above all for shadowing (Fig.lb).Simple ion guns of low energy (some keV) however, yield a relatively low ion current, so that coatings with materials which are difficult to sputter, such as tungsten, can hardly be produced. With ions of higher energy the gain of sputtering particles would certainly increase. However, the danger arises that ions scattered at the target and neutral particles of high energy could damage the specimen.The basic idea of the new sputter source consists of arranging the target inside the discharge chamber but the specimen outside of it (Fig.2).

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