scholarly journals Physical advantages of particles: protons and light ions

2020 ◽  
Vol 93 (1107) ◽  
pp. 20190428 ◽  
Author(s):  
Oliver Jäkel
Keyword(s):  
Energy Loss ◽  
Biological Effects ◽  
Ion Beam ◽  
National Laboratory ◽  
Carbon Ions ◽  
Nuclear Fragmentation ◽  
Depth Dose ◽  
Light Ions ◽  
Argon Ions ◽  
First Time

Proton and ion beam therapy has been introduced in the Lawrence Berkeley National Laboratory in the mid-1950s, when protons and helium ions have been used for the first time to treat patients. Starting in 1972, the scientists at Berkeley also were the first to use heavier ions (carbon, oxygen, neon, silicon and argon ions). The first clinical ion beam facility opened in 1994 in Japan and since then, the interest in radiotherapy with light ion beams has been increasing slowly but steadily, with 13 centers in clinical operation in 2019. All these centers are using carbon ions for clinical application. The article outlines the differences in physical properties of various light ions as compared to protons in view of the application in radiotherapy. These include the energy loss and depth dose properties, multiple scattering, range straggling and nuclear fragmentation. In addition, the paper discusses differences arising from energy loss and linear energy transfer with respect to their biological effects. Moreover, the paper reviews briefly the existing clinical data comparing protons and ions and outlines the future perspectives for the clinical use of ions like oxygen and helium.

scholarly journals Mapping the Relative Biological Effectiveness of Proton, Helium and Carbon Ions with High-Throughput Techniques

Cancers ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 3658
Author(s):  
Lawrence Bronk ◽  
Fada Guan ◽  
Darshana Patel ◽  
Duo Ma ◽  
Benjamin Kroger ◽  
...  
Keyword(s):  
High Throughput ◽  
Relative Biological Effectiveness ◽  
Biological Effects ◽  
Ion Beam ◽  
Particle Beam ◽  
Clonogenic Survival ◽  
Carbon Ions ◽  
Charged Particle Beams ◽  
Biological Effectiveness ◽  
Therapy Center

Large amounts of high quality biophysical data are needed to improve current biological effects models but such data are lacking and difficult to obtain. The present study aimed to more efficiently measure the spatial distribution of relative biological effectiveness (RBE) of charged particle beams using a novel high-accuracy and high-throughput experimental platform. Clonogenic survival was selected as the biological endpoint for two lung cancer cell lines, H460 and H1437, irradiated with protons, carbon, and helium ions. Ion-specific multi-step microplate holders were fabricated such that each column of a 96-well microplate is spatially situated at a different location along a particle beam path. Dose, dose-averaged linear energy transfer (LETd), and dose-mean lineal energy (yd) were calculated using an experimentally validated Geant4-based Monte Carlo system. Cells were irradiated at the Heidelberg Ion Beam Therapy Center (HIT). The experimental results showed that the clonogenic survival curves of all tested ions were yd-dependent. Both helium and carbon ions achieved maximum RBEs within specific yd ranges before biological efficacy declined, indicating an overkill effect. For protons, no overkill was observed, but RBE increased distal to the Bragg peak. Measured RBE profiles strongly depend on the physical characteristics such as yd and are ion specific.

scholarly journals Plant Mutation Breeding with Heavy Ion Irradiation at IMP

2016 ◽  
Vol 8 (5) ◽  
pp. 34 ◽  
Author(s):  
Xicun Dong ◽  
Xia Yan ◽  
Wenjian Li
Keyword(s):  
Ion Irradiation ◽  
Biological Effects ◽  
Ion Beam ◽  
National Laboratory ◽  
Heavy Ion ◽  
Mutation Breeding ◽  
High Yield ◽  
Early Maturity ◽  
Heavy Ion Irradiation ◽  
Heavy Ion Beam

<p>The Heavy Ion Research Facility in Lanzhou (HIRFL) is one of the ion-beam acceleration facilities intensively used at IMP, founded as national laboratory and opened for user in world from 1992. Since then, a lot of experiments irradiated by heavy ion beam have been carried out in the HIRFL, including plant mutation breeding. In this review, the biological effects induced by heavy ions and their corresponding mechanisms were reported from the point of view of cytological, morphological and molecular levels. To date, a large number of mutants were isolated using heavy ion irradiation IMP, such as early maturity, flower color and shape, high yield and disease resistant. In conclusion, heavy ion beam irradiation is an efficient mutagen and has significant phenotypic variations in plant. Our research will be further focused on transformation of scientific and technological achievements and mutagenic mechanism of heavy ion beam on high plant at the molecular level in the recent future.</p>

Electron energy loss spectroscopy of diamond-like carbon thin films

1992 ◽  
Vol 50 (2) ◽  
pp. 1272-1273
Author(s):  
J. Kulik ◽  
Y. Lifshitz ◽  
G.D. Lempert ◽  
S. Rotter ◽  
J.W. Rabalais ◽  
...  
Keyword(s):  
Thin Films ◽  
Energy Loss ◽  
Electron Energy ◽  
Ion Beam ◽  
Diamond Like Carbon ◽  
Ion Beam Deposition ◽  
Chemistry Research ◽  
Carbon Thin Films ◽  
Electron Energy Loss ◽  
Beam Deposition

Carbon thin films with diamond-like properties have generated significant interest in condensed matter science in recent years. Their extreme hardness combined with insulating electronic characteristics and high thermal conductivity make them attractive for a variety of uses including abrasion resistant coatings and applications in electronic devices. Understanding the growth and structure of such films is therefore of technological interest as well as a goal of basic physics and chemistry research. Recent investigations have demonstrated the usefulness of energetic ion beam deposition in the preparation of such films. We have begun an electron microscopy investigation into the microstructure and electron energy loss spectra of diamond like carbon thin films prepared by energetic ion beam deposition.The carbon films were deposited using the MEIRA ion beam facility at the Soreq Nuclear Research Center in Yavne, Israel. Mass selected C+ beams in the range 50 to 300 eV were directed onto Si {100} which had been etched with HF prior to deposition.

Electron and ion irradiation-induced dissolution of mechanical twins in the intermetalic U3Si: An in situ HVEM study

1989 ◽  
Vol 47 ◽  
pp. 652-653
Author(s):  
Charles W. Allen ◽  
Robert C. Birtcher
Keyword(s):  
Elevated Temperatures ◽  
Ion Irradiation ◽  
Ion Beam ◽  
National Laboratory ◽  
Argonne National Laboratory ◽  
Heavy Ion ◽  
High Energy ◽  
Mechanical Twinning ◽  
In Situ Experiments

The uranium silicides, including U3Si, are under study as candidate low enrichment nuclear fuels. Ion beam simulations of the in-reactor behavior of such materials are performed because a similar damage structure can be produced in hours by energetic heavy ions which requires years in actual reactor tests. This contribution treats one aspect of the microstructural behavior of U3Si under high energy electron irradiation and low dose energetic heavy ion irradiation and is based on in situ experiments, performed at the HVEM-Tandem User Facility at Argonne National Laboratory. This Facility interfaces a 2 MV Tandem ion accelerator and a 0.6 MV ion implanter to a 1.2 MeV AEI high voltage electron microscope, which allows a wide variety of in situ ion beam experiments to be performed with simultaneous irradiation and electron microscopy or diffraction.At elevated temperatures, U3Si exhibits the ordered AuCu3 structure. On cooling below 1058 K, the intermetallic transforms, evidently martensitically, to a body-centered tetragonal structure (alternatively, the structure may be described as face-centered tetragonal, which would be fcc except for a 1 pet tetragonal distortion). Mechanical twinning accompanies the transformation; however, diferences between electron diffraction patterns from twinned and non-twinned martensite plates could not be distinguished.

scholarly journals Direct detection of atomic dark matter in white dwarfs

2021 ◽  
Vol 2021 (3) ◽  
Author(s):  
David Curtin ◽  
Jack Setford
Keyword(s):  
Dark Matter ◽  
Energy Loss ◽  
Cooling Rate ◽  
White Dwarf ◽  
White Dwarfs ◽  
Luminosity Function ◽  
Direct Detection ◽  
Matter Density ◽  
Mixing Parameter ◽  
First Time

Abstract Dark matter could have a dissipative asymmetric subcomponent in the form of atomic dark matter (aDM). This arises in many scenarios of dark complexity, and is a prediction of neutral naturalness, such as the Mirror Twin Higgs model. We show for the first time how White Dwarf cooling provides strong bounds on aDM. In the presence of a small kinetic mixing between the dark and SM photon, stars are expected to accumulate atomic dark matter in their cores, which then radiates away energy in the form of dark photons. In the case of white dwarfs, this energy loss can have a detectable impact on their cooling rate. We use measurements of the white dwarf luminosity function to tightly constrain the kinetic mixing parameter between the dark and visible photons, for DM masses in the range 10−5–105 GeV, down to values of ϵ ∼ 10−12. Using this method we can constrain scenarios in which aDM constitutes fractions as small as 10−3 of the total dark matter density. Our methods are highly complementary to other methods of probing aDM, especially in scenarios where the aDM is arranged in a dark disk, which can make direct detection extremely difficult but actually slightly enhances our cooling constraints.

Energy Loss of a Low-Energy Ion Beam in Passage through an Equilibrium Cesium Plasma

1972 ◽  
Vol 28 (19) ◽  
pp. 1254-1258 ◽  
Author(s):  
I. L. Klavan ◽  
D. M. Cox ◽  
H. H. Brown ◽  
B. Bederson
Keyword(s):  
Energy Loss ◽  
Ion Beam ◽  
Low Energy ◽  
Cesium Plasma

MeV Self Ion Beam Induced Amorphisation of Silicon Carbide Surfaces and Its Effect on Their Trdbomechanical Propertdzs

1991 ◽  
Vol 235 ◽  
Author(s):  
D. K. Sood ◽  
V. C. Nath ◽  
Yang Xi
Keyword(s):  
Silicon Carbide ◽  
Raman Scattering ◽  
High Precision ◽  
Friction And Wear ◽  
Ion Beam ◽  
Steel Ball ◽  
Carbon Ions ◽  
Ion Energy ◽  
Number Of Cycles ◽  
Tribomechanical Properties

ABSTRACTAmorphisation of sintered SiC by bombardment with self (C, Si) ions has been studied. Ion doses ranged from 1×1015 to 1×1017 ions/cm2; and ion energy was varied from 0.09 to 5 MeV. Amorphisation was detected by micro-focus Raman scattering. Tribomechanical properties-friction and wear were studied with a high precision pin (steel ball) and disc (implanted) machine. Results show substantial improvements in friction and wear, which persist to a large number of cycles. Tribomechanical properties are shown to correlate with surface amorphisation and carburisation. Carbon ions are found to be much more effective than Si ions (with similar damage distributions) in reducing friction and wear.

Description of (Hyper-)Fragments in Hadron-Induced Reactions

Symmetry ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1887
Author(s):  
Theodoros Gaitanos
Keyword(s):  
Nuclear Reactions ◽  
Heavy Ion ◽  
Nuclear Fragmentation ◽  
Equilibrium Dynamics ◽  
Ion Collisions ◽  
Light Ions ◽  
Classical Transport ◽  
Nuclear Targets ◽  
Fragmentation Processes

In this article we review the important role of non-equilibrium dynamics in reactions induced by ions and hadron beams to understand the fragmentation processes inside hadronic media. We discuss the single-particle dynamics in specific sources such as spectators in heavy-ion collisions and residual nuclear targets in hadron-induced reactions. Particular attention is given to the dynamics of hyperons. We further discuss the question regarding the onset of local instabilities, which are relevant for the appearance of fragmentation phenomena in nuclear reactions. We apply the theoretical formalism, that is, semi-classical transport embedded with statistical methods of nuclear fragmentation, to reactions induced by light ions and hadron beams. We discuss the results of nuclear fragmentation and, in particular, examine the formation of hypernuclei. Such studies are important for obtaining a deeper understanding of the equation of state in fragmenting matter and are relevant for forthcoming experiments, such as PANDA at FAIR and J-PARC in Japan.

scholarly journals The high current experiment: First results

2002 ◽  
Vol 20 (3) ◽  
pp. 435-440 ◽  
Author(s):  
P.A. SEIDL ◽  
D. BACA ◽  
F.M. BIENIOSEK ◽  
A. FALTENS ◽  
S.M. LUND ◽  
...  
Keyword(s):  
Space Charge ◽  
Ion Beam ◽  
Beam Steering ◽  
Fusion Energy ◽  
National Laboratory ◽  
Heavy Ion ◽  
High Current ◽  
Current Experiment ◽  
First Results ◽  
High Space

The High Current Experiment (HCX) is being assembled at Lawrence Berkeley National Laboratory as part of the U.S. program to explore heavy ion beam transport at a scale representative of the low-energy end of an induction linac driver for fusion energy production. The primary mission of this experiment is to investigate aperture fill factors acceptable for the transport of space-charge dominated heavy ion beams at high space-charge intensity (line-charge density ∼ 0.2 μC/m) over long pulse durations (>4 μs). This machine will test transport issues at a driver-relevant scale resulting from nonlinear space-charge effects and collective modes, beam centroid alignment and beam steering, matching, image charges, halo, lost-particle induced electron effects, and longitudinal bunch control. We present the first experimental results carried out with the coasting K+ ion beam transported through the first 10 electrostatic transport quadrupoles and associated diagnostics. Later phases of the experiment will include more electrostatic lattice periods to allow more sensitive tests of emittance growth, and also magnetic quadrupoles to explore similar issues in magnetic channels with a full driver scale beam.

Sign in / Sign up

Export Citation Format

Share Document