85 lines
4.6 KiB
Text
85 lines
4.6 KiB
Text
The present advances in accelerator based RT, like FLASH RT or micro beam RT,
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lead to operation parameters of the accelerator that can not anymore be described
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by simple linear optics and beam dynamics. Instead, the consideration of nonlinear
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and complex optics as well as beam dynamics influenced by collective effects becomes
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necessary due to the development towards higher charge and energy combined with shorter
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pulse lengths and transverse modulations.
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my experience in longitudinal as well as transverse collective effects and instabilities
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influencing the electron bunch shape in all dimensions....
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at rings but focus on single bunch effects can be transferred to linac..
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simulations as well as experimental studies...
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also diagnostics, used electron-beam based as well as synchrotron-radiation based and improved and developed further diagnostic methods ...
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Much data analysis... and investigating new phenomena occuring in extrem operation modes...
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bridge gap between accelerator science and medical physics
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study from accelerator point of view all the beam dynamics effects relevant in the generation
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of such beams as well as the diagnostic to reliably deliver the predicted conditions.
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Furthermore, extent the simulations of the beam dynamics beyond the end of the accelerator
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all the way into the target, by including the transport in air and water/matter.
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This will allow the prediction of the temporal and spacial shape (shape and length) of
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the radiation/electron pulse not only at the exit of the accelerator but also at any diagnostic
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on the way and finally also at the target inside the patient.
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beam-matter interaction have been described in the past by covariance matrices...(based on e.g. scattering angles(?)...)
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which was applied e.g. for thin foils in the beam path.
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This can be applied for calculating the impact of the beam-matter interaction
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on the beam properties during the transport all the way to the target.
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the feasibility and the accuracy of predicting the beam properties on target is improved.
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In case, the spacial structuring of the beam on target is relevant,
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it is important to know how the spacial distribution changes along the way from generation to the target.
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With simulations including the beam-matter interaction as well as collective effects within the beam
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On top of this, calculations of the collective effects occurring within the high intensity beam
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can be added using established(?) algorithms/predictions/theoretical descriptions usually applied
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to beam dynamics calculations within the accelerator.
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The hope is that, by extending the calculation of these effects beyond the accelerator
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this can not only be predicted but already considered during the generation.
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Ideally, this would allow the generation of a spacial distribution which preemptively compensates for the expected changes.
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TEST with experiment and iteratively improve model....by testing impact and relevance of different effects
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(for example space charge, MORE effects?) in general and depending on the beam properties (energy, charge, custom(?) temporal and spacial pattern)
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in simulations as well as crosscheck with measurements
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TODO: rewrite with more focus on the FLASH und less on microbeams, but more as second schwerpunkt
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- https://doi.org/10.1016/S0958-3947(02)00086-9 shows electron beam through mask, but beamlets combine again after some 10 mmm. what if e beam directly micro structured, infestigate how this would propagate through accelerator and later through air, water and matter
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Dose-Volume Effect, where the tolerance of normal tissue to radiation
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damage increases dramatically as the radiation field size decreases, ???
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--------------------
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develop predictions/simulations as well as select correct diagnostics
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test both with measurements
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flash, short pulses but how short when arriving
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micro-structured beams
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spacial light modulator -> structuring possible but what arrives at target due to scattering and space charge effects (between beamlets)?!!
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pulse charakteristik bunch strukture, mikro beams
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probleme auch pulse längen messung nicht nur charge
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tests possible at different energies
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flute as rf-based accelerator and maybe ATHENA as laser based accelerator as (preliminary) source of short electron pulses
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THz/x-ray from KARA?
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these studies will define an optimal set...
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these studies will provide simulation tools(?)/simulations for ...(pulse customarily shaped in space and time) ( transport through accelerator to target supported by specialized(?) diagnostics)
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the research aims to greatly extend/improve/....
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have been developed and ready to be adapted.
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will be investigated as required
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pave the way towards....
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beam modalities
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an unmet challenge
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