ISSN:0033-7579    

DOI:10.1080/00337577708233116

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

Despite many successful applications of non-photographic dielectric track detectors in numerous scientific and technological fields, the basic mechanisms of track formation and development are still rather unknown for these detectors. In this paper an attempt is made to estimate the relative importance for track formation in plastics of direct interactions of heavy charged particles and of events of their secondary electrons. Both classes of events are weighted rather differently in existent track formation models. The discussion is mainly based on results obtained from calculations on the spatial distribution of events along and around the paths of fast ions and of electrons.

ISSN:0033-7579    

DOI:10.1080/00337577708233117

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

From the very beginning of solid state track detector measurements two track formation theories were used: the models of the restricted energy loss (RED and the primary ionization (PI). Both theories include different adjustable parameters. Performing the calibration at the same ion (e.g. Fe) the differences of the mass determination as a function of charge for both track formation theories will be shown. The calculations will be compared with experimental data.

ISSN:0033-7579    

DOI:10.1080/00337577708233118

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

Nuclear emulsions processed in discriminating developers, intended to suppress small latent image sites, exhibit supralinear sensitometric blackness-exposure curves, whose character varies according to developing time, concentration, and composition, yielding hittedness ranging from 1 to 8, singly and in combination. These emulsion-processing combinations display the phenomena called ion-kill (sensitization by the transit of a single charged particle) and gamma- kill (sensitization by the overlap of secondary electron paths, whether from x-rays or from the delta-rays of heavy ions) in radiobiology. Here emulsions are blackened by x-rays when these same plates reveal no electron tracks, or no alpha-particle tracks, or even no fission fragment tracks. The supralinearity of the emulsion response to x-rays, and the consequent suppression of low LET radiations suggest that these materials have the potential to mimic the response of biological systems to particulate radiations of different charge and speed.

ISSN:0033-7579    

DOI:10.1080/00337577708233119

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

Fast moving heavy charged particles passing through solids are mainly losing their energy—in a wide range of velocities—by excitation and ionization processes which result in a more or less stable radiation damage.1The radiation damage may consist of broken bonds, free radicals, chemical reaction products, displaced atoms, ionic and electronic defects, dislocation configurations, voids, clusters of defects with and without impurities, nuclei of new phases etc. The nature and stability of this localized radiation damage, termed the “latent” track of the particle depends on the data of the particle and on the physical and chemical properties of the solid. Dielectric materials with low electric and thermal conductivities offer favorable conditions for relatively high local excitation and ionization densities resulting in physical and chemical solid state reactions with relatively stable reaction Products.

ISSN:0033-7579    

DOI:10.1080/00337577708233120

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

In recent years significant achievements in the field of silver chloride track detector preparation were obtained mainly due to efforts of German specialists from Frankfurt/Main and Munich.1,2On the basis of silver chloride crystals doped with lead and cadmium (or calcium), track detectors with sensitivity to charged particles which could be switched on and off by exposing to yellow light radiation were obtained.

ISSN:0033-7579    

DOI:10.1080/00337577708233121

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

The effects of the energetic ions implantation in AgCl can be related to two types of perturbation due to: the electronic energy losses observed, essentially with H+(2 MeV) implantation and the collision energy losses illustrated in K+(0.5 MeV) implantation.

ISSN:0033-7579    

DOI:10.1080/00337577708233122

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

The behaviour of the latent image produced by actinic radiation (λ = 365 nm and λ = 407 nm) in AgCl monocrystal foils highly doped with Cd and grown and annealed under various conditions was studied by extinction measurements in the near infrared. The photographic elementary process in these highly doped crystals cannot be described satisfactorily by the classical Gurney Mott model. Therefore another model was used based on the creation of anion vacancies and molecular chlorine complexes. The radiation-induced electrons occupy these anion vacancies, and quasi- metallic centres are formed. By this model the behaviour of the light-induced latent image can also be described as the nuclear particle track formation in the Cd doped AgCl crystals.

ISSN:0033-7579    

DOI:10.1080/00337577708233123

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

Charged particles travelling through an organic medium leave a trail of highly concentrated active, stable chemical radicals. These functions are able to initiate copolymerization reactions of unsaturated molecules. Such a reagent is made to reach the trail; polymerization occurs. If the new polymer formed either absorbs or emits light the track of the charged particle is made visible. This technique and results are discussed: the efficiency of those detectors has been increased, they do not exhibit any critical dip angle for the registration of particle tracks, they may offer a way to reveal tracks originating in the detector itself.

ISSN:0033-7579    

DOI:10.1080/00337577708233124

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

The basic properties of the electrochemical track etching method proposed by Tommasino were studied for PC and PET foils irradiated with fission fragments and/or alpha-particles. Etching was performed in a specially designed double-wall vessel applying electric fields of different strengths and frequencies. The variation in the diameters of the discharge spots produced around the tracks of fission fragments entering PC and PET foils at right angles was systematically studied as a function of the strength and frequency of the electric field, etching time and etchant temperature. For alpha-tracks registered in PC foils the dependence of the discharge spot diameter on particle energy was also determined. It was found that the production of discharge spots started at a threshold field strength depending on the type of particle. The temperature dependence of the growing rate of discharge spots followed the Arrhenius law, but with a reduced activation energy as compared to that obtained for the chemical etching rate of the bulk material.

ISSN:0033-7579    

DOI:10.1080/00337577708233125

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor