Uncored betatron BIM-M a source of bremsstrahlung for flash radiography

Particle beam radiography, which uses a variety of particle probes (neutrons, protons, electrons, gammas and potentially other particles) to study the structure of materials and objects noninvasively, is reviewed, largely from an accelerator perspective, although the use of cosmic rays (mainly muons but potentially also high-energy neutrinos) is briefly reviewed. Tomography is a form of radiography which uses multiple views to reconstruct a three-dimensional density map of an object. There is a very wide range of applications of radiography and tomography, from medicine to engineering and security, and advances in instrumentation, specifically the development of electronic detectors, allow rapid analysis of the resultant radiographs. Flash radiography is a diagnostic technique for large high-explosive-driven hydrodynamic experiments that is used at many laboratories. The bremsstrahlung radiation pulse from an intense relativistic electron beam incident onto a high-Z target is the source of these radiographs. The challenge is to provide radiation sources intense enough to penetrate hundreds of g/cm 2 of material, in pulses short enough to stop the motion of high-speed hydrodynamic shocks, and with source spots small enough to resolve fine details. The challenge has been met with a wide variety of accelerator technologies, including pulsed-power-driven diodes, air-core pulsed betatrons and high-current linear induction accelerators. Accelerator technology has also evolved to accommodate the experimenters' continuing quest for multiple images in time and space. Linear induction accelerators have had a major role in these advances, especially in providing multiple-time radiographs of the largest hydrodynamic experiments.

show abstract

“…The newest and largest betatron at VNIIEF is BIM-M [60,61]. The BIM-M injector is a cold cathode diode driven by a Marx/pulseline/MITL.…”

Section: Pulsed Air-core Betatronsmentioning

confidence: 99%

Particle Beam Radiography

Peach

Ekdahl

2013

Rev. Accl. Sci. Tech.

View full text Add to dashboard Cite

show abstract

“…The newest and largest betatron at VMIEF is BIM-M [4]. The BIM-M injector is a cold-cathode diode driven by a Marx/pulselineMTL, This prodtxes a 2-MeV, 10-kA, 15-ns electron beam.…”

Section: Pulsed Betatronsmentioning

confidence: 99%

Modern electron accelerators for radiography

Ekdahl¹

PPPS-2001 Pulsed Power Plasma Science 2001. 28th IEEE International Conference on Plasma Science and 13th IEEE International Pu

View full text Add to dashboard Cite

LOS Alam~s NaUonal Laboratory, ai1 affirmative rrctionkiqunl cpportunity employer, is operated by the University of Califomla for the US.Deprtmnt of Energy under conhct W-7'405-ENG-36. By acceptance of'this article, the publisher recognizes that the US. Government rehinS a nonexdusb, royalty-Ira llcsrtse to publish or reproduce the published form ofthk cctntribution. or to allow others to do SO, for US.Govemmunt purposes. Los Alaimos National Laboratory requests Usat the publisher identify ais affide as work performed under the amplceS Of the U.S. Depcwtrnent of Energy. 1-0s Alamos National Laboratory strongly supports academlc freedm and a researcher's right to publish; at: an Instltutlon, however, the Lahatory does not endorse the viewpoint of a publication or guarantee Hs technical correctness. ODERN ELECSITRON ACCELERATORS FOR RADIOGRAPHY Carl EkdahlLos ,4Eamos Natioml I~boratory, Los Alamos, NM, USA AbstractOver the past dozen years or so there have been significant advances in electron accelerators designed specifically for radiography of hydrodynamic experiments. Accelerator Eechnology has evolved to a c c o m d i t e the mdiojgaphers' contitiuing quest for multiple images in t h e and space:, hprovements in electron beam quality have resulted in smaller radiographic spot sizes for better resolution, while higher radiation do% now provides imprcwed penetration of large, dense objects. Inductive isolation and acceleration techniques have played a ley rob in these advances.The development of electron accelerators for radiography at many laboratories around the world has been motivated by a need for high-resolution data from hydrodynamic experiments driven by high explosives. Some of the largest hydrodynamic experiments study the implosion of mockups of nuclear weapons in which the actinides have been by non-fissile metals. These largescale implos ments are often called Point-projection radiography is the most common technique used to inlage these dynamic experiments. A pulsed "pinl" source of penetrating bremsstrahlung photons illuminates the object from behind, projecting a "snapshot" of the hytirodynamic effects onto a large area f i l m or camaa-based imaging systeim. Improvement of the quality of these images has motivated have evolved through cotisideration of how axekCaEOr parameters can improve the quality of these radiographic images.Stopping the action to minimize hjdrdpamic-motion blur contriMbn to byatid resolution sets the maximum permissible pulse-width of the accelerated electron beam.Shock pressures in high-explosive driven hydrodynamic experiments are multi-megabar, and corresponding shock velocities exceed 1 d p s , so the bremsstrahlung radiation pulse must be 100 ns or less to achieve millimeter scale resolution. Therefore, the accelerator must be capable of producing radiation at a high dose rate, in order to produce sufficient dose for a high-quality image within the short pulsewidth. Bremsstrahlung dose rate is proportional to I@"7, where I is the beam current and E is the beam energy...

show abstract