51 research outputs found
Radiotherapy using a laser proton accelerator
Laser acceleration promises innovation in particle beam therapy of cancer
where an ultra-compact accelerator system for cancer beam therapy can become
affordable to a broad range of patients. This is not feasible without the
introduction of a technology that is radically different from the conventional
accelerator-based approach. The laser acceleration method provides many
enhanced capabilities for the radiation oncologist. It reduces the overall
system size and weight by more than one order of magnitude. The characteristics
of the particle beams (protons) make them suitable for a class of therapy that
might not be possible with the conventional accelerator, such as the ease for
changing pulse intensity, the focus spread, the pinpointedness, and the dose
delivery in general. A compact, uncluttered system allows a PET device to be
located in the vicinity of the patient in concert with the compact gantry. The
radiation oncologist may be able to irradiate a localized tumor by scanning
with a pencil-like particle beam while ascertaining the actual dosage in the
patient with an improved in-beam PET verification of auto-radioactivation
induced by the beam therapy. This should yield an unprecedented flexibility in
the feedback radiotherapy by the radiation oncologist. Laser accelerated
radiotherapy has a unique niche in a current world of high energy accelerator
using synchrotron or cyclotron.Comment: 26 pages, 8 figures, 2 tables, 69 references. International Symposium
on Laser-Driven Relativistic Plasmas Applied for Science, Industry and
Medicine, Kyoto, Japan, 17-20 September (2007
X-ray harmonic comb from relativistic electron spikes
X-ray devices are far superior to optical ones for providing nanometre
spatial and attosecond temporal resolutions. Such resolution is indispensable
in biology, medicine, physics, material sciences, and their applications. A
bright ultrafast coherent X-ray source is highly desirable, for example, for
the diffractive imaging of individual large molecules, viruses, or cells. Here
we demonstrate experimentally a new compact X-ray source involving high-order
harmonics produced by a relativistic-irradiance femtosecond laser in a gas
target. In our first implementation using a 9 Terawatt laser, coherent soft
X-rays are emitted with a comb-like spectrum reaching the 'water window' range.
The generation mechanism is robust being based on phenomena inherent in
relativistic laser plasmas: self-focusing, nonlinear wave generation
accompanied by electron density singularities, and collective radiation by a
compact electric charge. The formation of singularities (electron density
spikes) is described by the elegant mathematical catastrophe theory, which
explains sudden changes in various complex systems, from physics to social
sciences. The new X-ray source has advantageous scalings, as the maximum
harmonic order is proportional to the cube of the laser amplitude enhanced by
relativistic self-focusing in plasma. This allows straightforward extension of
the coherent X-ray generation to the keV and tens of keV spectral regions. The
implemented X-ray source is remarkably easily accessible: the requirements for
the laser can be met in a university-scale laboratory, the gas jet is a
replenishable debris-free target, and the harmonics emanate directly from the
gas jet without additional devices. Our results open the way to a compact
coherent ultrashort brilliant X-ray source with single shot and high-repetition
rate capabilities, suitable for numerous applications and diagnostics in many
research fields
Laser driven ion source
The laser driven ion source development especially the authors own work was mainly described at the meeting as an invited talk. The recent achievement of monochromatization technique for proton generation was reported.The Third International Conference on Super-strong Fields in Plasma
X-Ray Lasers 2016
These proceedings comprise a selection of invited and contributed papers presented at the 15th International Conference on X-Ray Lasers (ICXRL 2016), held at the Nara Kasugano International Forum, Japan, from May 22 to 27, 2016. This conference was part of an ongoing series dedicated to recent developments in the science and technology of x-ray lasers and other coherent x-ray sources with additional focus on supporting technologies, instrumentation and applications. The book showcases recent advances in the generation of intense, coherent x-rays, the development of practical devices and their applications across a wide variety of fields. It also discusses emerging topics such as plasma-based x-ray lasers, 4th generation accelerator-based sources and higher harmonic generations, as well as other x-ray generation schemes
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