Selective X-ray generation by heavy ions (Part 2) measurement of the concentration distribution of ion-implanted antimony in silicon by the use of selective heavy ion X-ray excitation

1971 ◽  
Vol 7 (3-4) ◽  
pp. 167-172 ◽  
Author(s):  
J. A. Cairns ◽  
D. F. Holloway ◽  
R. S. Nelson
Keyword(s):  
Heavy Ions ◽  
Concentration Distribution ◽  
Heavy Ion ◽  
X Ray ◽  
Ion Implanted

Heavy Ion-Induced Characteristic X-Ray Generation as an Analytical Probe

1970 ◽  
Vol 14 ◽  
pp. 173-183 ◽  
Author(s):  
J. A. Cairns ◽  
D. F. Holloway ◽  
R. S. Nelson
Keyword(s):  
Cross Sections ◽  
Heavy Ions ◽  
Proton Irradiation ◽  
Heavy Ion ◽  
X Rays ◽  
X Ray ◽  
The Past ◽  
Tracer Techniques ◽  
New Type ◽  
Gas Volume

AbstractIncreasing attention is currently focused on the generation of characteristic x-ray by proton irradiation. This has the advantage of yielding “clean” x-ray- i. e. free from background brerasstrahlung radiation, from even the lightest elements. The disadvantage is that the yields are naturally much lower than those produced by electrons of the same energy. A recent study has extended characteristic x-ray production to a variety of heavy ions and has shown that the cross- sections for the production of clean x-rays are often higher , by as much as several orders of magnitude, than those produced by protons of the same energy. In addition, there has emerged a further advantage, viz. the ability of specially chosen heavy ions to excite characteristic x-ray from a particular element in a selective manner. Since heavy ions penetrate only a few hundred Angstroms in to most solids, the phenomenon can be used as the basis of a technique for the examination of surface deposits, or to measure depth distributions of impurities. For example, Kr ions can be used t o determine the range distribution of antimony which had been implanted in to silicon at 100 keV. The antimony concentration was determined as a function of ∼ 150 Å steps, and was found to exhibit a maximum concentration of ∼ 1 part in 103 of silicon at 450 Å below the surface, falling to zero concentration at ∼2000 Å a depth. In the past, in order to obtain the required degree of sensitivity, such range determinations have relied on radio active tracer techniques.An entirely new type of proportional counter has been developed during the course of these studies. This instrument, because of its special construction, can be positioned very close to targets in non-dispersive studies, so as to collect the highest possible fraction of emitted x-ray. It incorporates a replaceable anode unit, together with a built- in miniature head amplifier, and exhibits extremely good performance, particularly for ultra-soft x-ray. In addition, rotation of a dial on the end of the counter body allows alteration of the active gas volume during operation, and so permits tuning into x-rays of a particular energy.

scholarly journals Identification of Ka X-ray Satellite Lines Induced by MeV Heavy-ion Bombardment of Elemental Targets

1974 ◽  
Vol 27 (2) ◽  
pp. 177 ◽  
Author(s):  
FP Larkins
Keyword(s):  
Heavy Ions ◽  
Ion Bombardment ◽  
Heavy Ion ◽  
Detailed Calculation ◽  
Transition Processes ◽  
X Ray ◽  
Hartree Fock ◽  
Direct Participation ◽  
Silicon System ◽  
Atomic Species

It is shown that multiply ionized atoms with one or two holes in the 2s subshell in addition to holes in the 2p subshell may contribute directly to the observed Krx. satellite and hypersatellite spectra reported for targets bombarded with highly energetic heavy ions. The direct participation of such defect configurations results because the normally rapid Ll -L23M Coster-Kronig transition processes are energetically forbidden for most excited atomic species that are multiply ionized in the L shell. Adiabatic nonrelativistic Hartree-Fock calculations are presented to support this conclusion. A detailed calculation for the Krx. satellite and hypersatellite spectra of the silicon system is given.

scholarly journals Biologic Impact of Different Ultra-Low-Fluence Irradiations in Human Fibroblasts

Life ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 154 ◽  
Author(s):  
Masao Suzuki ◽  
Yukio Uchihori ◽  
Hisashi Kitamura ◽  
Masakazu Oikawa ◽  
Teruaki Konishi
Keyword(s):  
Gamma Rays ◽  
Heavy Ions ◽  
Cellular Response ◽  
Mutation Frequency ◽  
Human Fibroblasts ◽  
Cellular Responses ◽  
Heavy Ion ◽  
Iron Ions ◽  
X Ray ◽  
Challenging Dose

In this study, we aimed to evaluate the cellular response of healthy human fibroblasts induced by different types of ultra-low-fluence radiations, including gamma rays, neutrons and high linear energy transfer (LET) heavy ions. NB1RGB cells were pretreated with ultra-low-fluence radiations (~0.1 cGy/7–8 h) of 137Cs gamma rays, 241Am–Be neutrons, helium, carbon and iron ions before being exposed to an X-ray-challenging dose (1.5 Gy). Helium (LET = 2.3 keV/µm), carbon (LET = 13.3 keV/µm) and iron (LET = 200 keV/µm) ions were generated with the Heavy Ion Medical Accelerator in Chiba (HIMAC), Japan. No differences in cell death—measured by colony-forming assay—were observed regardless of the radiation type applied. In contrast, mutation frequency, which was detected through cell transformation into 6-thioguanine resistant clones, was 1.9 and 4.0 times higher in cells pretreated with helium and carbon ions, respectively, compared to cells exposed to X-ray-challenging dose alone. Moreover, cells pretreated with iron ions or gamma-rays showed a mutation frequency similar to cells exposed to X-ray-challenging dose alone, while cells pretreated with neutrons had 0.15 times less mutations. These results show that cellular responses triggered by ultra-low-fluence irradiations are radiation-quality dependent. Altogether, this study shows that ultra-low-fluence irradiations with the same level as those reported in the International Space Station are capable of inducing different cellular responses, including radio-adaptive responses triggered by neutrons and genomic instability mediated by high-LET heavy ions, while electromagnetic radiations (gamma rays) seem to have no biologic impact.

scholarly journals Microcalorimeters for X-Ray Spectroscopy of Highly Charged Ions at Storage Rings

Atoms ◽  
2018 ◽  
Vol 6 (4) ◽  
pp. 59 ◽  
Author(s):  
Saskia Kraft-Bermuth ◽  
Daniel Hengstler ◽  
Peter Egelhof ◽  
Christian Enss ◽  
Andreas Fleischmann ◽  
...  
Keyword(s):  
Heavy Ions ◽  
Lamb Shift ◽  
Ion Beam ◽  
Heavy Ion ◽  
Storage Rings ◽  
Highly Charged Ions ◽  
Semiconductor Detectors ◽  
X Ray ◽  
Charged Ions

X-ray spectroscopy of highly charged heavy ions is an important tool for the investigation of many topics in atomic physics. Such highly charged ions, in particular hydrogen-like uranium, are investigated at heavy ion storage rings, where high charge states can be produced in large quantities, stored for long times and cooled to low momentum spread of the ion beam. One prominent example is the determination of the 1s Lamb Shift in hydrogen-like heavy ions, which has been investigated at the Experimental Storage Ring (ESR) at the GSI Helmholtz Centre for Heavy Ion Research. Due to the large electron binding energies, the energies of the corresponding photon transitions are located in the X-ray regime. To determine the transition energies with high accuracy, highly resolving X-ray spectrometers are needed. One concept of such spectrometers is the concept of microcalorimeters, which, in contrast to semiconductor detectors, uses the detection of heat rather than charge to detect energy. Such detectors have been developed and successfully applied in experiments at the ESR. For experiments at the Facility for Antiproton and Ion Research (FAIR), the Stored Particles and Atoms Collaboration (SPARC) pursues the development of new microcalorimeter concepts and larger detector arrays. Next to fundamental investigations on quantum electrodynamics such as the 1s Lamb Shift or electron–electron interactions in two- and three-electron systems, X-ray spectroscopy may be extended towards nuclear physics investigations like the determination of nuclear charge radii.

scholarly journals Heavy ion charge states in Jupiter’s polar magnetosphere inferred from auroral megavolt electric potentials

2020 ◽  
Author(s):  
George Clark ◽  
Barry Mauk ◽  
Peter Kollmann ◽  
Chris Paranicas ◽  
Fran Bagenal ◽  
...  
Keyword(s):  
Heavy Ions ◽  
Heavy Ion ◽  
Physical Processes ◽  
Polar Cap ◽  
X Ray ◽  
Jovian Magnetosphere ◽  
Electric Potentials ◽  
Charge States ◽  
Sparse Measurements ◽  
Mass Dependent

<p>In this presentation, we exploit the charge-dependent nature of field-aligned potentials in Jupiter’s polar cap auroral region to infer the charge states of energetic oxygen and sulfur. To-date, there are very limited and sparse measurements of the > 50 keV oxygen and sulfur charge states, yet many studies have demonstrated their importance in understanding the details of various physical processes, such as, X-ray aurora, ion-neutral interactions in Jupiter’s neutral cloud and particle acceleration theories. In this contribution, we develop a technique to determine the most abundant charge states associated with heavy ions in Jupiter’s polar magnetosphere. We find that O<sup>+</sup> and S<sup>++</sup> are the most abundant and therefore iogenic in origin. The results are important because they provide 1) strong evidence that soft X-ray sources are likely due to charge stripping of magnetospheric ions and; 2) a more complete spatial map of the oxygen and sulfur charge states, which is important for understanding how the charge- and mass-dependent physical processes sculpt the energetic particles throughout the Jovian magnetosphere. </p>

Axial Observation of X-Ray Spectra from a Beam-Foil Source

1988 ◽  
Vol 102 ◽  
pp. 339-342
Author(s):  
J.M. Laming ◽  
J.D. Silver ◽  
R. Barnsley ◽  
J. Dunn ◽  
K.D. Evans ◽  
...  
Keyword(s):  
Spectral Resolution ◽  
Heavy Ion ◽  
Ion Beams ◽  
Beam Axis ◽  
Doppler Broadening ◽  
X Ray ◽  
Beam Foil

AbstractNew observations of x-ray spectra from foil-excited heavy ion beams are reported. By observing the target in a direction along the beam axis, an improvement in spectral resolution, δλ/λ, by about a factor of two is achieved, due to the reduced Doppler broadening in this geometry.

Multi-scale Investigation of Heterogeneous Swift Heavy Ion Tracks in Stannate Pyrochlore

2021 ◽  
Author(s):  
Eric O'Quinn ◽  
Cameron Tracy ◽  
William F. Cureton ◽  
Ritesh Sachan ◽  
Joerg C. Neuefeind ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Heavy Ion ◽  
X Ray Diffraction ◽  
X Ray ◽  
Structural Modifications ◽  
Multi Scale ◽  
Ion Tracks ◽  
Swift Heavy Ion ◽  
Transmission Electron

Er2Sn2O7 pyrochlore was irradiated with swift heavy Au ions (2.2 GeV), and the induced structural modifications were systematically examined using complementary characterization techniques including transmission electron microscopy (TEM), X-ray diffraction...

scholarly journals Proton therapy for craniopharyngioma in adults: a protocol for systematic review and meta-analysis

BMJ Open ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. e046043
Author(s):  
Pengtao Li ◽  
Jialing Wang ◽  
Aximujiang Axier ◽  
Kai Zhou ◽  
Jingwei Yun ◽  
...  
Keyword(s):  
Proton Therapy ◽  
Ion Beam ◽  
Grey Literature ◽  
Intervention Group ◽  
Heavy Ion ◽  
Cochrane Library ◽  
Secondary Outcome ◽  
Significant Heterogeneity ◽  
Recurrence Rates ◽  
X Ray

IntroductionCraniopharyngioma is the most challenging to treat brain tumour with high recurrence rates, which can be effectively reduced by adjuvant radiotherapy. In recent years, proton therapy (PT), with its physical properties of heavy ion beam, that is, Prague peak phenomenon, has been more frequently used in patients with craniopharyngioma. Compared with conventional X-ray beam radiotherapy, PT can reduce the damage to normal tissues and enlarge the damage to tumours. Some studies have shown that PT has advantages in the treatment of craniopharyngioma in adults. However, the optimal management of craniopharyngioma remains controversial. The purpose of this study was to evaluate the efficacy and safety of PT for craniopharyngioma in adults.Methods and analysisWe will search six databases (MEDLINE, EMBASE, Web of Science, the Cochrane Library, Amed, Scopus), clinical research registration websites and grey literature, aiming to identify randomised controlled trials (RCTs) on PT for craniopharyngioma in adults between 1 January 1954 and 28 September 2021. In the RCTs, PT will be used as the intervention group, and conventional X-ray beam radiotherapy will be used as the comparator group. Tumour recurrence and survival will be the primary outcome, and treatment-related toxicity will be the secondary outcome. The study selection, data extraction, bias risk and quality evaluation will be operated by two to four researchers independently. We will use Review Manager V.5.2 (RevMan V.5.2) for data analysis. If there is significant heterogeneity, we will identify the source of heterogeneity by subgroup analysis.Ethics and disseminationOur study is based on existing RCTs and does not require ethical approval. The results of the study will be published in a peer-reviewed journal or at a related conference.PROSPERO registration numberCRD42020200909.

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