Physics design of the CiADS MEBT

2021 ◽  
pp. 2150127
Author(s):  
Weilong Chen ◽  
Zhijun Wang ◽  
Shuhui Liu ◽  
Chi Feng ◽  
Mengxin Xu ◽  
...  
Keyword(s):  
Beam Quality ◽  
Beam Power ◽  
Beam Emittance ◽  
Energy Beam ◽  
Machine Errors ◽  
Space Distortion ◽  
Under Construction ◽  
Superconducting Accelerator ◽  
Production Target ◽  
Subcritical System

The superconducting linac for China initiative Accelerator Driven Subcritical System (CiADS) is the world-leading ADS-driver under construction with state-of-the-art technologies. This system is designed to accelerate a 5 mA proton beam to 500 MeV energy, and then delivering 2.5 MW of beam power to the neutron production target. The Middle Energy Beam Transport (MEBT) is designed with great emphasis on smoothing matching between the upstream and downstream acceleration sections, beam diagnostics layout and beam quality control. It is proposed and successfully implemented to immigrate the phase space distortion and reduce the increase of beam emittance. The acceptance of MEBT is optimized to make all the particles inside the effective acceptance of the superconducting section even with machine errors. This pertinent design of MEBT is suitable for the high-power superconducting accelerator of CiADS.

scholarly journals Solid Target System with In-Situ Target Dissolution

Instruments ◽  
2019 ◽  
Vol 3 (1) ◽  
pp. 14 ◽  
Author(s):  
William Z. Gelbart ◽  
Richard R. Johnson
Keyword(s):  
Target Material ◽  
Incident Beam ◽  
Chemistry Laboratory ◽  
Target System ◽  
Beam Power ◽  
New Approach ◽  
Target Station ◽  
Production Target ◽  
Design Construction

A significant number of medical radioisotopes use solid, often metallic, parent materials.These materials are deposited on a substrate to facilitate the cooling and handling of the targetduring placing, irradiation, and processing. The processing requires the transfer of the target to aprocessing area outside the irradiation area. In this new approach the target is processed at theirradiation site for liquid only transport of the irradiated target material to the processing area. Thedesign features common to higher energy production target systems are included in the targetstation. The target is inclined at 14 degrees to the beam direction. The system has been designed toaccept an incident beam of 15 to 16 mm diameter and a beam power between 2 and 5 kW. Thermalmodeling is presented for targets of metals and compounds. A cassette of five or 10 preparedtargets is housed at the target station as well as a target dissolution assembly. Only the dissolvedtarget material is transported to the chemistry laboratory so that the design does not requireadditional irradiation area penetrations. This work presents the design, construction, and modelingdetails of the assembly. A full performance characterization will be reported after the unit is movedto a cyclotron facility for beam related measurements.

Fast neutrons at LNL Legnaro

2020 ◽  
pp. 1-15
Author(s):  
Pierfrancesco Mastinu ◽  
Dario Bisello ◽  
Rogelio Alfonso Barrera ◽  
Ignacio Porras ◽  
Gianfranco Prete ◽  
...  
Keyword(s):  
Cosmic Ray ◽  
Neutron Production ◽  
Fast Neutrons ◽  
General Interest ◽  
Air Showers ◽  
Space Applications ◽  
Microelectronic Devices ◽  
Energy Peak ◽  
Under Construction ◽  
Production Target

In this contribution we describe NEPIR, the fast-neutron irradiation facility under construction at the 70 MeV cyclotron SPES facility of the INFN laboratory of Legnaro (LNL). NEPIR will be constructed in stages, according to the available funds. The initial configuration, based on a thick Be neutron production target, will be operational in 2022; it will be used for shielding studies against fast neutrons for space applications and to investigate neutron-induced Single Event Effects (SEE) in microelectronic devices and systems. In its final configuration NEPIR will have two target systems: one will deliver a Quasi Mono-energetic Neutron (QMN) beam, of general interest, with an adjustable energy peak in the 20–70 MeV range; the second target will deliver a specialized continuous energy neutron beam for studying the effects of fast neutrons produced in cosmic ray air-showers in electronic devices and systems. We review the use of NEPIR to characterize the sensitivity of electronics, describe the neutron production targets and the facility layout. In closing we describe ways, presently under investigation, to use the 15 MV XTU Tandem of LNL to produce nearly monochromatic fast neutrons that would complement the QMN system by allowing one to probe for SEE below 20 MeV.

Z-SCANS WITH NEAR-GAUSSIAN LASER BEAMS

1996 ◽  
Vol 05 (02) ◽  
pp. 419-436 ◽  
Author(s):  
P.B. CHAPPLE ◽  
P.J. WILSON
Keyword(s):  
Beam Quality ◽  
Laser Beams ◽  
Beam Power ◽  
Gaussian Beams ◽  
Optical Nonlinearities ◽  
Beam Quality Factor ◽  
Laboratory Measurements ◽  
Waist Size ◽  
The Difference ◽  
T Values

Laboratory measurements of optical nonlinearities can be significantly affected by imperfections in the laser beam profiles. Here the effects of beam profile on Z-scan measurements are calculated for a large number of near-Gaussian beams. These effects are modeled for Z-scans of thin media, for both refractive and absorptive nonlinearities. The difference ∆T between the maximum and minimum values of the normalized transmittance generally increases with the beam quality factor M2 (as the beam quality declines). for a given beam power and waist size. The scatter in ∆T values also increases with M2.

High-Intensity Bremsstrahlung of Electron Accelerator in Photoneutron and Radioisotopes Production for Medicine

2019 ◽  
Vol 64 (5) ◽  
pp. 48-53
Author(s):  
Ю. Кураченко ◽  
Yu. Kurachenko ◽  
Е. Онищук ◽  
E. Onischuk ◽  
Е. Матусевич ◽  
...  
Keyword(s):  
Heavy Metal ◽  
Neutron Capture ◽  
Specific Activity ◽  
Radiation Transport ◽  
Beam Quality ◽  
Beam Power ◽  
Liquid Gallium ◽  
Neutron Capture Therapy ◽  
Bremsstrahlung Radiation ◽  
Electron Accelerators

Purpose: To study the binary possibility of using the available linear electron accelerators for the neutron therapy and radioisotopes production. For both applications, calculations were performed and the results were normalized to the characteristics of the Mevex accelerator (average electron current 4 mA at a monoenergetic electron beam 35 MeV). It turns out that the production of both photoneutrons and radioisotopes is effective when using bremsstrahlung radiation generated in the giant dipole resonance of a heavy metal target. Material and methods: The unifying problem for both applications is the task of target cooling: at beam power ~ 140 kW, half of it or more is deposited directly in the target. Therefore the liquid heavy metal was selected as a target, in order to conjoin high thermohydraulics quality with maximal productivity both bremsstrahlung radiation and photoneutrons. The targets were optimized using precise codes for radiation transport and thermohydraulics problems. The optimization was also carried out for the installations as a whole: 1) for the composition of the material and configuration of the photoneutron extraction unit for neutron capture therapy (NCT) and 2) for the scheme of bremsstrahlung generation for radioisotopes production. Results: The photoneutron block provides an acceptable beam quality for NCT with a high neutron flux density at the output ~2·1010 cm–2s–1, which is an order of magnitude higher than the values at the output of the reactor beams that worked in the past and are currently being designed for neutron capture therapy. As for radioisotopes production, using optimal reaction channel (γ, n) 43 radioisotopes in 5 groups were received. For example, by the Mo100(γ,n)99Mo reaction the precursor 99Mo of main diagnostic nuclide 99mTc with specific activity ~6 Ci/g and total activity of the target 1.8 kCi could be produced after 1 day irradiation exposure. Conclusion: The proposed schemes of neutron and bremsstrahlung generation and extraction have a number of obvious advantages over traditional techniques: a) the applying of the electron accelerators for neutron production is much safer and cheaper than to use conventional reactor beams; b) accelerator with the target, the beam output unit with the necessary equipment and tooling can be placed on the territory of the clinic without any problems; c) the proposed target for NCT is liquid gallium, which also serves as a coolant; it is an “environmentally friendly” material, its activation is rather low and rapidly (in ~4 days) falls to the background level.

Study on Universal Standard for Evaluating High Energy Beam Quality

2009 ◽  
Vol 36 (4) ◽  
pp. 773-778 ◽  
Author(s):  
刘泽金 Liu Zejin ◽  
周朴 Zhou Pu ◽  
许晓军 Xu Xiaojun
Keyword(s):  
Beam Quality ◽  
High Energy ◽  
Energy Beam ◽  
Universal Standard ◽  
High Energy Beam

scholarly journals Latest developments in in-vivo imaging for proton therapy

2020 ◽  
Vol 93 (1107) ◽  
pp. 20190787 ◽  
Author(s):  
Katia Parodi
Keyword(s):  
Beam Quality ◽  
Medical Physics ◽  
Ion Beam ◽  
Biological Properties ◽  
Actual Patient ◽  
In Silico Studies ◽  
Ion Therapy ◽  
Beam Delivery ◽  
Under Construction

Owing to the favorable physical and biological properties of swift ions in matter, their application to radiation therapy for highly selective cancer treatment is rapidly spreading worldwide. To date, over 90 ion therapy facilities are operational, predominantly with proton beams, and about the same amount is under construction or planning. Over the last decades, considerable developments have been achieved in accelerator technology, beam delivery and medical physics to enhance conformation of the dose delivery to complex shaped tumor volumes, with excellent sparing of surrounding normal tissue and critical organs. Nevertheless, full clinical exploitation of the ion beam advantages is still challenged, especially by uncertainties in the knowledge of the beam range in the actual patient anatomy during the fractionated course of treatment, thus calling for continued multidisciplinary research in this rapidly emerging field. This contribution will review latest developments aiming to image the patient with the same beam quality as for therapy prior to treatment, and to visualize in-vivo the treatment delivery by exploiting irradiation-induced physical emissions, with different level of maturity from proof-of-concept studies in phantoms and first in-silico studies up to clinical testing and initial clinical evaluation.

Research on Near Space Optical Communication Transmitting and Receiving Technology

2014 ◽  
Vol 721 ◽  
pp. 678-681
Author(s):  
Wei Da Zhan ◽  
Dong Ya Xiao ◽  
Zi Qiang Hao ◽  
Hong Zuo Li
Keyword(s):  
Laser Beam ◽  
Optical Communication ◽  
Laser Energy ◽  
Beam Quality ◽  
Beam Power ◽  
Communication Link ◽  
Beam Diameter ◽  
Near Space ◽  
Link Distance ◽  
Space Optical Communication

In near space optical communication, the laser beam energy affects communication link distance directly, also laser beam quality affects the laser energy density, modulation efficiency, bit error rate (BER) of communication and other parameters. In this paper we have presented an experiment system of space optical communication, of which the transmitting power is 1w, modulation rate is 500 Mbps and link distance is 8 to 10 kilometers. Then the effects of optical fiber collimator, electro-optic modulator, optical antenna and other units on beam power loss, beam diameter, divergence angle and other parameters are analyzed. Last we put forward the way of increasing the laser transmitting distance and the optimization measure of system key unit.

Electron Beam Deflection When Welding Dissimilar Metals

1990 ◽  
Vol 112 (3) ◽  
pp. 714-720 ◽  
Author(s):  
P. S. Wei ◽  
T. W. Lii
Keyword(s):  
Electron Beam ◽  
Incident Angle ◽  
Electrical Contact ◽  
Beam Deflection ◽  
Beam Power ◽  
Dissimilar Metals ◽  
Electrical Contact Resistance ◽  
Energy Beam ◽  
Relative Magnetic Permeability ◽  
The Difference

High-intensity electron beam deflection due to thermoelectric magnetism generated during the welding of dissimilar metals is systematically and analytically investigated. A simple thermoelectric model is proposed and the temperature field, penetration depth of the fusion zone, magnetic field, and motion of an electron are determined. Deviation of the fused zone from a joint is affected by the incident angle of the energy beam, the difference in Seebeck coefficients of workpieces, relative magnetic permeability, beam power, welding speed, thermal and electrical conductivities, and the effective electrical contact resistance. Their effects are clearly interpreted in this study. Analytical results for the deviation of the fused zone from the joint between the materials to be welded show good agreement with available experimental data.

scholarly journals Zero-Compression, Laminar Electron Beam Generation in a Uniform Magnetic Field

2021 ◽  
Author(s):  
Robert Jackson ◽  
R. L. Ives ◽  
M. E. Read
Keyword(s):  
Magnetic Field ◽  
High Power ◽  
Uniform Magnetic Field ◽  
High Current Density ◽  
Beam Quality ◽  
Radial Electric Field ◽  
Initial Result ◽  
Beam Power ◽  
Surprising Result ◽  
Cyclotron Motion

<div> <div> <div> <p>The need for enhanced performance of high- power RF vacuum electron devices has led to investigation of multiple-beam, sheet beam and annular beam configu- rations. A key issue with such devices is the magnetic field shaping required to produce high-power, laminar beams. Field shaping is difficult when Pierce-type gun geometries are employed. The development of high current density cathodes makes the necessary beam power achievable without compression. Such cathodes can operate within a uniform magnetic field yielding advantages for both single and distributed-beam RF devices. However, the quality of the resulting beams presents problems. A project to optimize beam quality in zero-convergence electron guns was undertaken by Calabazas Creek Research (CCR) and North Carolina State University (NCSU). The surprising result was that high quality electron beams can be gener- ated in uniform magnetic fields using convex (dome) shaped cathodes. The underlying physics involves perturbation of the beam cyclotron motion by a non-adiabatic radial electric field impulse. This paper examines this physical mechanism and extends the initial result to additional diode and beam geometries. </p> </div> </div> </div>

High-Intensity Bremsstrahlung of Electron Accelerator in Photoneutron and Radioisotopes Production for Medicine

2019 ◽  
Vol 64 (5) ◽  
pp. 42-47
Author(s):  
Ю. Кураченко ◽  
Yu. Kurachenko ◽  
Е. Онищук ◽  
E. Onischuk ◽  
Е. Матусевич ◽  
...  
Keyword(s):  
Heavy Metal ◽  
Neutron Capture ◽  
Specific Activity ◽  
Radiation Transport ◽  
Beam Quality ◽  
Beam Power ◽  
Liquid Gallium ◽  
Neutron Capture Therapy ◽  
Bremsstrahlung Radiation ◽  
Electron Accelerators

Purpose: To study the binary possibility of using the available linear electron accelerators for the neutron therapy and radioisotopes production. For both applications, calculations were performed and the results were normalized to the characteristics of the Mevex accelerator (average electron current 4 mA at a monoenergetic electron beam 35 MeV). It turns out that the production of both photoneutrons and radioisotopes is effective when using bremsstrahlung radiation generated in the giant dipole resonance of a heavy metal target. Material and methods: The unifying problem for both applications is the task of target cooling: at beam power ~ 140 kW, half of it or more is deposited directly in the target. Therefore the liquid heavy metal was selected as a target, in order to conjoin high thermohydraulics quality with maximal productivity both bremsstrahlung radiation and photoneutrons. The targets were optimized using precise codes for radiation transport and thermohydraulics problems. The optimization was also carried out for the installations as a whole: 1) for the composition of the material and configuration of the photoneutron extraction unit for neutron capture therapy (NCT) and 2) for the scheme of bremsstrahlung generation for radioisotopes production. Results: The photoneutron block provides an acceptable beam quality for NCT with a high neutron flux density at the output ~2·1010 cm–2s–1, which is an order of magnitude higher than the values at the output of the reactor beams that worked in the past and are currently being designed for neutron capture therapy. As for radioisotopes production, using optimal reaction channel (γ, n) 43 radioisotopes in 5 groups were received. For example, by the Mo100(γ,n)99Mo reaction the precursor 99Mo of main diagnostic nuclide 99mTc with specific activity ~6 Ci/g and total activity of the target 1.8 kCi could be produced after 1 day irradiation exposure. Conclusion: The proposed schemes of neutron and bremsstrahlung generation and extraction have a number of obvious advantages over traditional techniques: a) the applying of the electron accelerators for neutron production is much safer and cheaper than to use conventional reactor beams; b) accelerator with the target, the beam output unit with the necessary equipment and tooling can be placed on the territory of the clinic without any problems; c) the proposed target for NCT is liquid gallium, which also serves as a coolant; it is an “environmentally friendly” material, its activation is rather low and rapidly (in ~4 days) falls to the background level.

Sign in / Sign up

Export Citation Format

Share Document