Enhanced collective stopping and drift of electron beams in fusion plasmas with heavy-ion species

Experimental studies of atomic physics are performed with heavy-ion beams from accelerators at RIKEN. The variety of ion species and wide range of velocities and charge states enable us to study atomic collision processes and spectroscopy of highly charged ions. An overview of the works is presented.

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Research into the advanced experimental methods for precision ion stopping range measurements in matter

Laser and Particle Beams ◽

10.1017/s0263034602211015 ◽

2003 ◽

Vol 21 (1) ◽

pp. 1-6 ◽

Cited By ~ 10

Author(s):

I.E. BAKHMETJEV ◽

A.D. FERTMAN ◽

A.A. GOLUBEV ◽

A.V. KANTSYREV ◽

V.E. LUCKJASHIN ◽

...

Keyword(s):

Energy Deposition ◽

Experimental Methods ◽

Heavy Ion ◽

Ion Beams ◽

Measured Data ◽

Thick Target ◽

Solid Matter ◽

Ion Energy ◽

Ion Species ◽

Noticeable Discrepancy

The article presents the results of the experimental research on precision measurement of total stopping range and energy deposition function of intermediate and heavy ion beams in cold solid matter. The “thick target” method proves to be appropriate for this purpose. Two types of detectors were developed which provide an error of the total stopping range measurement of less than 3% and of the beam energy deposition function of about 7%. The experiments with 58Ni+26, 197Au+65, and 238U+72 ion beams in the energy range 100–300 MeV/u were performed on SIS-18 (Gesellschaft für Schwerionenforschung, Darmstadt) in 1999–2001. The measured data on the total stopping ranges for the above ion species in bulk and foiled Al and Cu targets are presented. The investigation showed that there is a noticeable discrepancy between the measured stopping ranges and the theoretically predicted ones. Also, it was shown that realistic ion energy deposition depends on the type of target (bulk or foiled). Further investigation is necessary to clarify the latter.

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Nonlinear 1-D stationary flows in multi-ion plasmas – sonic and critical loci – solitary and "oscillatory" waves

Annales Geophysicae ◽

10.5194/angeo-24-3041-2006 ◽

2006 ◽

Vol 24 (11) ◽

pp. 3041-3057 ◽

Cited By ~ 7

Author(s):

E. M. Dubinin ◽

K. Sauer ◽

J. F. McKenzie

Keyword(s):

Magnetic Field ◽

Critical Points ◽

Heavy Ion ◽

Energy Functions ◽

Ion Motion ◽

Stationary Flows ◽

Energy Integrals ◽

Ion Cloud ◽

Ion Species ◽

The Magnetic Field

Abstract. One-dimensional stationary flows of a plasma consisting of two ion populations and electrons streaming against a heavy ion cloud are studied. The flow structure is critically governed by the position of sonic and critical points, at which the flow is shocked or choked. The concept of sonic and critical points is suitably generalized to the case of multi-ion plasmas to include a differential ion streaming. For magnetic field free flows, the sonic and critical loci in the (upx, uhx) space coincide. Amongst the different flow patterns for the protons and heavy ions, there is a possible configuration composed of a "heavy ion shock" accompanied by a proton rarefaction. The magnetic field introduces a "stiffness" for the differential ion streaming transverse to the magnetic field. In general, both ion fluids respond similarly in the presence of "ion obstacle"; the superfast (subfast) flows are decelerated (accelerated). The collective flow is choked when the dynamic trajectory (upx, uhx) crosses the critical loci. In specific regimes the flow contains a sequence of solitary structures and as a result, the flow is strongly bunched. In each such substructure the protons are almost completely replaced by the heavies. A differential ion streaming is more accessible in the collective flows oblique to the magnetic field. Such a flexibility of the ion motion is determined by the properties of energy integrals and the Bernoulli energy functions of each ion species. The structure of flows, oblique to the magnetic field, depends critically on the velocity regime and demonstrates a rich variety of solitary and oscillatory nonlinear wave structures. The results of the paper are relevant to the plasma and field environments at comets and planets through the interaction with the solar wind.

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Proton and heavy ion acceleration by stochastic fluctuations in the Earth's magnetotail

Annales Geophysicae ◽

10.5194/angeo-34-917-2016 ◽

2016 ◽

Vol 34 (10) ◽

pp. 917-926 ◽

Cited By ~ 7

Author(s):

Filomena Catapano ◽

Gaetano Zimbardo ◽

Silvia Perri ◽

Antonella Greco ◽

Anton V. Artemyev

Keyword(s):

Magnetic Field ◽

Three Dimensional ◽

Heavy Ion ◽

Ion Acceleration ◽

Acceleration Process ◽

Magnetic Field Profile ◽

Stochastic Fluctuations ◽

Particle Simulations ◽

Simulation Parameters ◽

Ion Species

Abstract. Spacecraft observations show that energetic ions are found in the Earth's magnetotail, with energies ranging from tens of keV to a few hundreds of keV. In this paper we carry out test particle simulations in which protons and other ion species are injected in the Vlasov magnetic field configurations obtained by Catapano et al. (2015). These configurations represent solutions of a generalized Harris model, which well describes the observed profiles in the magnetotail. In addition, three-dimensional time-dependent stochastic electromagnetic perturbations are included in the simulation box, so that the ion acceleration process is studied while varying the equilibrium magnetic field profile and the ion species. We find that proton energies of the order of 100 keV are reached with simulation parameters typical of the Earth's magnetotail. By changing the ion mass and charge, we can study the acceleration of heavy ions such as He+ + and O+, and it is found that energies of the order of 100–200 keV are reached in a few seconds for He+ + , and about 100 keV for O+.

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Ion Colliders

Reviews of Accelerator Science and Technology ◽

10.1142/s1793626814300047 ◽

2014 ◽

Vol 07 ◽

pp. 49-76 ◽

Cited By ~ 3

Author(s):

Wolfram Fischer ◽

John M. Jowett

Keyword(s):

Nuclear Physics ◽

Collision Energy ◽

Hadron Collider ◽

Heavy Ion ◽

Gluon Plasma ◽

High Energy ◽

Heavy Nuclei ◽

Relativistic Heavy Ion Collider ◽

Polarized Protons ◽

Ion Species

High energy ion colliders are large research tools in nuclear physics for studying the quark–gluon–plasma (QGP). The collision energy and high luminosity are important design and operational considerations. The experiments also expect flexibility with frequent changes in the collision energy, detector fields, and ion species. Ion species range from protons, including polarized protons in RHIC, to heavy nuclei like gold, lead, and uranium. Asymmetric collision combinations (such as protons against heavy ions) are also essential. For the creation, acceleration, and storage of bright intense ion beams, limits are set by space charge, charge change, and intrabeam scattering effects, as well as beam losses due to a variety of other phenomena. Currently, there are two operating ion colliders: the Relativistic Heavy Ion Collider (RHIC) at BNL and the Large Hadron Collider (LHC) at CERN.

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Superconducting Hadron Linacs

Reviews of Accelerator Science and Technology ◽

10.1142/s1793626813300089 ◽

2013 ◽

Vol 06 ◽

pp. 171-196 ◽

Cited By ~ 2

Author(s):

Peter Ostroumov ◽

Frank Gerigk

Keyword(s):

High Intensity ◽

Continuous Wave ◽

Beam Quality ◽

Building Blocks ◽

Heavy Ion ◽

Design Concepts ◽

Beam Halo ◽

Light Ions ◽

Ion Proton ◽

Ion Species

This article discusses the main building blocks of a superconducting (SC) linac, the choice of SC resonators, their frequencies, accelerating gradients and apertures, focusing structures, practical aspects of cryomodule design, and concepts to minimize the heat load into the cryogenic system. It starts with an overview of design concepts for all types of hadron linacs differentiated by duty cycle (pulsed or continuous wave) or by the type of ion species (protons, H -, and ions) being accelerated. Design concepts are detailed for SC linacs in application to both light ion (proton, deuteron) and heavy ion linacs. The physics design of SC linacs, including transverse and longitudinal lattice designs, matching between different accelerating–focusing lattices, and transition from NC to SC sections, is detailed. Design of high-intensity SC linacs for light ions, methods for the reduction of beam losses, preventing beam halo formation, and the effect of HOMs and errors on beam quality are discussed. Examples are taken from existing designs of continuous wave (CW) heavy ion linacs and high-intensity pulsed or CW proton linacs. Finally, we review ongoing R&D work toward high-power SC linacs for various applications.

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