Experimental approach to measure thick target neutron yields induced by heavy ions for shielding

Momentum transfer in the fragmentation of copper by 400-GeV protons

Canadian Journal of Chemistry ◽

10.1139/v83-129 ◽

1983 ◽

Vol 61 (4) ◽

pp. 697-700 ◽

Cited By ~ 4

Author(s):

James B. Cumming

Keyword(s):

Momentum Transfer ◽

Heavy Ions ◽

Thick Target ◽

Simple Relationship ◽

Fragmentation Region ◽

Energy Transfers ◽

Limiting Fragmentation ◽

Technique Comparison

Mean momenta transferred to products of the fragmentation of copper by 400-GeV protons have been determined by the thick-target thick-catcher technique. Comparison with data for incident protons and heavy ions indicates that the limiting fragmentation region has been reached and supports a simple relationship between momentum and energy transfers in peripheral reactions which had been proposed previously.

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The stopping power of heavy ions for energies below 0.2 MeV/nucleon measured by the semi-thick target method

Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment ◽

10.1016/j.nima.2014.11.066 ◽

2015 ◽

Vol 774 ◽

pp. 82-88

Author(s):

A.A. Pasternak ◽

I. Sankowska ◽

A. Tucholski ◽

J. Srebrny ◽

T. Morek ◽

...

Keyword(s):

Heavy Ions ◽

Thick Target ◽

Stopping Power

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Thick Target Neutron Yield by Heavy Ions

Nuclear Data for Science and Technology - Research Reports in Physics ◽

10.1007/978-3-642-58113-7_215 ◽

1992 ◽

pp. 748-750

Author(s):

Kazuo Shin ◽

Kagetomo Miyahara ◽

Yoshitomo Uwamino

Keyword(s):

Neutron Yield ◽

Heavy Ions ◽

Thick Target

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Measurements of Thick Target Neutron Yields from 100 to 800 MeV/Nucleon Heavy Ions

Journal of Nuclear Science and Technology ◽

10.1080/00223131.2000.10874861 ◽

2000 ◽

Vol 37 (sup1) ◽

pp. 135-141 ◽

Cited By ~ 1

Author(s):

Tadahiro Kurosawa ◽

Noriaki Nakao ◽

Takashi Nakamura ◽

Yoshitomo Uwamino ◽

Tokushi Shibata ◽

...

Keyword(s):

Heavy Ions ◽

Thick Target

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Experimental Determination of the Effective Resolution Limit in Thick Specimens at High Voltages

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100116942 ◽

1975 ◽

Vol 33 ◽

pp. 664-665

Author(s):

Mircea Fotino

Keyword(s):

Experimental Approach ◽

Chromatic Aberration ◽

Resolving Power ◽

Biological Research ◽

Specimen Thickness ◽

Resolution Limit ◽

High Voltage Electron Microscopy ◽

Voltage Electron ◽

Resolution Level

The use of thick specimens (0.5 μm to 5.0 μm or more) is one of the most resourceful applications of high-voltage electron microscopy in biological research. However, the energy loss experienced by the electron beam in the specimen results in chromatic aberration and thus in a deterioration of the effective resolving power. This sets a limit to the maximum usable specimen thickness when investigating structures requiring a certain resolution level.An experimental approach is here described in which the deterioration of the resolving power as a function of specimen thickness is determined. In a manner similar to the Rayleigh criterion in which two image points are considered resolved at the resolution limit when their profiles overlap such that the minimum of one coincides with the maximum of the other, the resolution attainable in thick sections can be measured by the distance from minimum to maximum (or, equivalently, from 10% to 90% maximum) of the broadened profile of a well-defined step-like object placed on the specimen.

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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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Malfunctional Reorganization in the Developing Limbo-Prefrontal System in Animals: Implications for Human Psychoses?

Zeitschrift für Neuropsychologie ◽

10.1024//1016-264x.12.1.8 ◽

2001 ◽

Vol 12 (1) ◽

pp. 8-14

Author(s):

Gertraud Teuchert-Noodt ◽

Ralf R. Dawirs

Keyword(s):

Prefrontal Cortex ◽

Mental Disorders ◽

Dentate Gyrus ◽

Cognitive Functions ◽

Experimental Approach ◽

Regulatory Mechanisms ◽

Hippocampal Dentate Gyrus ◽

Non Invasive ◽

Invasive Method ◽

Activity Dependent

Abstract: Neuroplasticity research in connection with mental disorders has recently bridged the gap between basic neurobiology and applied neuropsychology. A non-invasive method in the gerbil (Meriones unguiculus) - the restricted versus enriched breading and the systemically applied single methamphetamine dose - offers an experimental approach to investigate psychoses. Acts of intervening affirm an activity dependent malfunctional reorganization in the prefrontal cortex and in the hippocampal dentate gyrus and reveal the dopamine position as being critical for the disruption of interactions between the areas concerned. From the extent of plasticity effects the probability and risk of psycho-cognitive development may be derived. Advance may be expected from insights into regulatory mechanisms of neurogenesis in the hippocampal dentate gyrus which is obviously to meet the necessary requirements to promote psycho-cognitive functions/malfunctions via the limbo-prefrontal circuit.

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