Lifetime assessment of functional components in the ESS target environment during beam energy ramp up

2020 ◽  
Vol 22 (2-3) ◽  
pp. 299-308
Author(s):  
Yongjoong Lee
Keyword(s):  
Radiation Damage ◽  
Proton Beam ◽  
Beam Energy ◽  
Neutron Production ◽  
Target Station ◽  
Fundamental Properties ◽  
Radiation Induced ◽  
Spallation Source ◽  
Target Environment ◽  
Functional Components

The Target Station at the European Spallation Source (ESS) is designed to convert high power proton beam to high brightness neutron beams, for studying fundamental properties of materials. Upon commissioning of the ‘beam on target’ planned in 2022, the ESS linac will deliver lower energy proton beam than the design value of 2 GeV, for neutron production. The beam energy will then be gradually ramped up, with the sequential commissioning of the downstream part of the superconducting cryomodules. During neutron production, the beam intercepting devices and moderators are exposed to intense flux of primary and secondary particles, suffering from radiation induced structural degradation. The extent of the radiation damage depends on the energy and intensity of the impinging protons. Currently, the lifetime criteria determined for these components are based on the 2 GeV beam energy. To secure availability and reliability of the neutron production during the beam energy ramp-up phase, the radiation damage rates in these components should be reassessed and the lifetime criteria be adjusted. In this paper, we present the lifetime criteria for the beam intercepting devices and moderators for different beam energies, to serve for the planning of the maintenance and replacement schedule during the proton energy ramp-up phase.

scholarly journals The Italian contribution to the construction of the linac for the European spallation source

2021 ◽  
Author(s):  
S. Gammino ◽  
A. Fabris ◽  
M. Lindroos
Keyword(s):  
Proton Beam ◽  
Point Of View ◽  
Social Experiment ◽  
The European Union ◽  
Research Facility ◽  
Target Station ◽  
Key Issues ◽  
Spallation Source ◽  
Scientific Challenge ◽  
High Level

AbstractThe European spallation source (ESS) uses a linear accelerator (linac) to deliver the high intensity proton beam to the target station for producing intense beams of neutrons. At the exit of the linac, the proton beam will have 2 GeV energy and 62.5 mA current. The construction of an accelerator with the contribution of different laboratories is not a new concept but so far the laboratories were controlled by the same government (e.g. in USA and Japan) or they delivered components for an intergovernmental institution like CERN. The European Spallation Source is a research facility that gathers 40 active in-kind (IK) contributors from 13 States, even outside the European Union, so its construction is not only a technical and scientific challenge, but also an economic, political and social experiment. The case of the Italian contribution is interesting because of the structure of Italian industrial ecosystem, mostly based on small and medium-sized enterprises (SME), which may be unsuitable for the case of a research infrastructure which construction requires a high level of R&D investments. Conversely, the well-known flexibility of SME to adapt to the requirements have balanced the weakness and the results are satisfactory. Following the overview of the Linac design, the paper will focus on the key issues of the Italian contribution, the state of the project (73% completion up to now) along with the point of view of the ESS management and the lesson learnt; the major outcomes for the economy and society will complete the discussion.

Annealing Of Radiation Damage in Tungsten

1970 ◽  
Vol 28 ◽  
pp. 412-413
Author(s):  
Robert C. Rau ◽  
John Moteff
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Radiation Damage ◽  
Thermal Annealing ◽  
Neutron Fluence ◽  
Dislocation Loops ◽  
Defect Clusters ◽  
Polycrystalline Tungsten ◽  
Transmission Electron ◽  
Radiation Induced

Transmission electron microscopy has been used to study the thermal annealing of radiation induced defect clusters in polycrystalline tungsten. Specimens were taken from cylindrical tensile bars which had been irradiated to a fast (E > 1 MeV) neutron fluence of 4.2 × 1019 n/cm2 at 70°C, annealed for one hour at various temperatures in argon, and tensile tested at 240°C in helium. Foils from both the unstressed button heads and the reduced areas near the fracture were examined.Figure 1 shows typical microstructures in button head foils. In the unannealed condition, Fig. 1(a), a dispersion of fine dot clusters was present. Annealing at 435°C, Fig. 1(b), produced an apparent slight decrease in cluster concentration, but annealing at 740°C, Fig. 1(C), resulted in a noticeable densification of the clusters. Finally, annealing at 900°C and 1040°C, Figs. 1(d) and (e), caused a definite decrease in cluster concentration and led to the formation of resolvable dislocation loops.

Evaluation and treatment of children with radiation-induced cerebral vasculopathy

2019 ◽  
Vol 24 (6) ◽  
pp. 680-688
Author(s):  
David S. Hersh ◽  
Kenneth Moore ◽  
Vincent Nguyen ◽  
Lucas Elijovich ◽  
Asim F. Choudhri ◽  
...  
Keyword(s):  
Radiation Therapy ◽  
Proton Beam ◽  
Tumor Imaging ◽  
Clinic Visit ◽  
Surgical Patient ◽  
Beam Radiation ◽  
Proton Beam Radiotherapy ◽  
Cranial Radiation ◽  
Delayed Complication ◽  
Radiation Induced

OBJECTIVEStenoocclusive cerebral vasculopathy is an infrequent delayed complication of ionizing radiation. It has been well described with photon-based radiation therapy but less so following proton-beam radiotherapy. The authors report their recent institutional experience in evaluating and treating children with radiation-induced cerebral vasculopathy.METHODSEligible patients were age 21 years or younger who had a history of cranial radiation and subsequently developed vascular narrowing detected by MR arteriography that was significant enough to warrant cerebral angiography, with or without ischemic symptoms. The study period was January 2011 to March 2019.RESULTSThirty-one patients met the study inclusion criteria. Their median age was 12 years, and 18 (58%) were male. Proton-beam radiation therapy was used in 20 patients (64.5%) and photon-based radiation therapy was used in 11 patients (35.5%). Patients were most commonly referred for workup as a result of incidental findings on surveillance tumor imaging (n = 23; 74.2%). Proton-beam patients had a shorter median time from radiotherapy to catheter angiography (24.1 months [IQR 16.8–35.4 months]) than patients who underwent photon-based radiation therapy (48.2 months [IQR 26.6–61.1 months]; p = 0.04). Eighteen hemispheres were revascularized in 15 patients. One surgical patient suffered a contralateral hemispheric infarct 2 weeks after revascularization; no child treated medically (aspirin) has had a stroke to date. The median follow-up duration was 29.2 months (IQR 21.8–54.0 months) from the date of the first catheter angiogram to last clinic visit.CONCLUSIONSAll children who receive cranial radiation therapy from any source, particularly if the parasellar region was involved and the child was young at the time of treatment, require close surveillance for the development of vasculopathy. A structured and detailed evaluation is necessary to determine optimal treatment.

scholarly journals Molecular Hydrogen as a Potential Clinically Applicable Radioprotective Agent

2021 ◽  
Vol 22 (9) ◽  
pp. 4566
Author(s):  
Shin-ichi Hirano ◽  
Yusuke Ichikawa ◽  
Bunpei Sato ◽  
Haru Yamamoto ◽  
Yoshiyasu Takefuji ◽  
...  
Keyword(s):  
Radiation Damage ◽  
Molecular Hydrogen ◽  
Regulation Of Gene Expression ◽  
Animal Experiments ◽  
Radiation Energy ◽  
Water Radiolysis ◽  
Low Dose Radiation ◽  
Oxidizing Power ◽  
Radiation Induced ◽  
Radioprotective Agent

Although ionizing radiation (radiation) is commonly used for medical diagnosis and cancer treatment, radiation-induced damages cannot be avoided. Such damages can be classified into direct and indirect damages, caused by the direct absorption of radiation energy into DNA and by free radicals, such as hydroxyl radicals (•OH), generated in the process of water radiolysis. More specifically, radiation damage concerns not only direct damages to DNA, but also secondary damages to non-DNA targets, because low-dose radiation damage is mainly caused by these indirect effects. Molecular hydrogen (H2) has the potential to be a radioprotective agent because it can selectively scavenge •OH, a reactive oxygen species with strong oxidizing power. Animal experiments and clinical trials have reported that H2 exhibits a highly safe radioprotective effect. This paper reviews previously reported radioprotective effects of H2 and discusses the mechanisms of H2, not only as an antioxidant, but also in intracellular responses including anti-inflammation, anti-apoptosis, and the regulation of gene expression. In doing so, we demonstrate the prospects of H2 as a novel and clinically applicable radioprotective agent.

scholarly journals Mesenchymal Stem Cell-Derived Exosomes: Biological Function and Their Therapeutic Potential in Radiation Damage

Cells ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 42
Author(s):  
Xiaoyu Pu ◽  
Siyang Ma ◽  
Yan Gao ◽  
Tiankai Xu ◽  
Pengyu Chang ◽  
...  
Keyword(s):  
Stem Cells ◽  
Mesenchymal Stem Cells ◽  
Stem Cell ◽  
Mesenchymal Stem Cell ◽  
Radiation Damage ◽  
Therapeutic Potential ◽  
Damage Model ◽  
Bioactive Substances ◽  
Radiation Induced ◽  
Insight Into

Radiation-induced damage is a common occurrence in cancer patients who undergo radiotherapy. In this setting, radiation-induced damage can be refractory because the regeneration responses of injured tissues or organs are not well stimulated. Mesenchymal stem cells have become ideal candidates for managing radiation-induced damage. Moreover, accumulating evidence suggests that exosomes derived from mesenchymal stem cells have a similar effect on repairing tissue damage mainly because these exosomes carry various bioactive substances, such as miRNAs, proteins and lipids, which can affect immunomodulation, angiogenesis, and cell survival and proliferation. Although the mechanisms by which mesenchymal stem cell-derived exosomes repair radiation damage have not been fully elucidated, we intend to translate their biological features into a radiation damage model and aim to provide new insight into the management of radiation damage.

Absolute polarimeter for the proton-beam energy of 200 MeV

2013 ◽  
Vol 76 (12) ◽  
pp. 1490-1496
Author(s):  
A. N. Zelenski ◽  
G. Atoian ◽  
A. A. Bogdanov ◽  
S. B. Nurushev ◽  
F. S. Pylaev ◽  
...  
Keyword(s):  
Proton Beam ◽  
Beam Energy ◽  
Proton Beam Energy

scholarly journals RNA protects a nucleoprotein complex against radiation damage

2016 ◽  
Vol 72 (5) ◽  
pp. 648-657 ◽  
Author(s):  
Charles S. Bury ◽  
John E. McGeehan ◽  
Alfred A. Antson ◽  
Ian Carmichael ◽  
Markus Gerstel ◽  
...  
Keyword(s):  
Radiation Damage ◽  
Rna Binding ◽  
Dose Range ◽  
Protein Molecule ◽  
Highly Sensitive ◽  
Structure Determinations ◽  
Binding Pockets ◽  
Radiation Induced ◽  
Damage Susceptibility ◽  
Dna Complex

Radiation damage during macromolecular X-ray crystallographic data collection is still the main impediment for many macromolecular structure determinations. Even when an eventual model results from the crystallographic pipeline, the manifestations of radiation-induced structural and conformation changes, the so-called specific damage, within crystalline macromolecules can lead to false interpretations of biological mechanisms. Although this has been well characterized within protein crystals, far less is known about specific damage effects within the larger class of nucleoprotein complexes. Here, a methodology has been developed whereby per-atom density changes could be quantified with increasing dose over a wide (1.3–25.0 MGy) range and at higher resolution (1.98 Å) than the previous systematic specific damage study on a protein–DNA complex. Specific damage manifestations were determined within the largetrpRNA-binding attenuation protein (TRAP) bound to a single-stranded RNA that forms a belt around the protein. Over a large dose range, the RNA was found to be far less susceptible to radiation-induced chemical changes than the protein. The availability of two TRAP molecules in the asymmetric unit, of which only one contained bound RNA, allowed a controlled investigation into the exact role of RNA binding in protein specific damage susceptibility. The 11-fold symmetry within each TRAP ring permitted statistically significant analysis of the Glu and Asp damage patterns, with RNA binding unexpectedly being observed to protect these otherwise highly sensitive residues within the 11 RNA-binding pockets distributed around the outside of the protein molecule. Additionally, the method enabled a quantification of the reduction in radiation-induced Lys and Phe disordering upon RNA binding directly from the electron density.

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