Accurate calculations for the Dirac electron in the field of two-center Coulomb field: Application to heavy ions

1988 ◽

Vol 03 (08) ◽

pp. 783-793 ◽

Cited By ~ 19

Author(s):

S. SCHRAMM ◽

B. MÜLLER ◽

J. REINHARDT ◽

W. GREINER

Keyword(s):

Heavy Ions ◽

Composite Particle ◽

Coulomb Field ◽

Particle Structure ◽

Bag Model ◽

Correlated Electron ◽

Mit Bag Model ◽

Hypothetical Explanation

An extended particle is discussed as the hypothetical source of correlated electron and positron lines observed at GSI. The particle structure is described in the framework of the MIT bag model. A mechanism for copious production in the Coulomb field of heavy ions is proposed.

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DIRAC ELECTRON IN A COULOMB FIELD IN (2+1) DIMENSIONS

Modern Physics Letters A ◽

10.1142/s0217732398000668 ◽

1998 ◽

Vol 13 (08) ◽

pp. 615-622 ◽

Cited By ~ 63

Author(s):

V. R. KHALILOV ◽

CHOON-LIN HO

Keyword(s):

Simple Model ◽

Dirac Equation ◽

Exact Solutions ◽

Coulomb Field ◽

Critical Charge ◽

Spatial Dimensions ◽

Dirac Electron

Exact solutions of Dirac equation in two spatial dimensions in the Coulomb field are obtained. Equation which determines the so-called critical charge of the Coulomb field is derived and solved for a simple model.

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Probing cosmic rays with Fe Kα line structures generated by multiple ionization process

Publications of the Astronomical Society of Japan ◽

10.1093/pasj/psaa055 ◽

2020 ◽

Vol 72 (4) ◽

Author(s):

Hiromichi Okon ◽

Makoto Imai ◽

Takaaki Tanaka ◽

Hiroyuki Uchida ◽

Takeshi Go Tsuru

Keyword(s):

Cosmic Rays ◽

Heavy Ions ◽

Supernova Remnants ◽

Line Emission ◽

Coulomb Field ◽

Galactic Cosmic Rays ◽

X Ray ◽

Strong Coulomb ◽

Novel Method ◽

Accelerated Particles

Abstract Supernova remnants (SNRs) have been regarded as major acceleration sites of Galactic cosmic rays. Recent X-ray studies revealed neutral Fe Kα line emission from dense gas in the vicinity of some SNRs, which can be best interpreted as K-shell ionization of Fe atoms in the gas by sub-relativistic particles accelerated in the SNRs. In this Letter, we propose a novel method of constraining the composition of particles accelerated in SNRs, which is currently unknown. When energetic heavy ions collide with target atoms, their strong Coulomb field can easily cause simultaneous ejection of multiple inner-shell electrons of the target. This results in shifts in characteristic X-ray line energies, forming distinctive spectral structures. Detection of such structures in the neutral Fe Kα line strongly supports the particle ionization scenario, and furthermore provides direct evidence of heavy ions in the accelerated particles. We construct a model for the Fe Kα line structures by various projectile ions utilizing atomic-collision data.

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Specimen Preparation of Near Surface Ion Irradiated Samples

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100117820 ◽

1985 ◽

Vol 43 ◽

pp. 170-171

Author(s):

K. F. Russell ◽

L. L. Horton

Keyword(s):

Radiation Damage ◽

Heavy Ions ◽

Target Material ◽

Metal Alloys ◽

Specimen Surface ◽

Specimen Preparation ◽

Particle Accelerators ◽

Near Surface ◽

Graaff Accelerator ◽

Van De Graaff

Beams of heavy ions from particle accelerators are used to produce radiation damage in metal alloys. The damaged layer extends several microns below the surface of the specimen with the maximum damage and depth dependent upon the energy of the ions, type of ions, and target material. Using 4 MeV heavy ions from a Van de Graaff accelerator causes peak damage approximately 1 μm below the specimen surface. To study this area, it is necessary to remove a thickness of approximately 1 μm of damaged metal from the surface (referred to as “sectioning“) and to electropolish this region to electron transparency from the unirradiated surface (referred to as “backthinning“). We have developed electropolishing techniques to obtain electron transparent regions at any depth below the surface of a standard TEM disk. These techniques may be applied wherever TEM information is needed at a specific subsurface position.

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