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