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Since October 2009 more than 2000 patients were treated at HIT. In a 24/7 operation scheme two 14.5 GHz electron cyclotron resonance ion sources are routinely used to produce protons and carbon ions for more than 8000 hours per year. The integration of a third ion source into the production facility was done in summer 2013 to produce a helium beam....
Contexts in source publication
Context 1
... beam production at HIT consists of two ECR Supernanogan ion sources [1] for the routine operation of proton and carbon beams at 8 keV/u; a third Supernanogan ion source is integrated (see ECR3 in Figure 2) for ion species like helium and oxygen for experiments at the experimental area (see Figure 1) and for the therapy in the future. ...
Context 2
... compact 217 MHz linear accelerator (LINAC) consists of a radio frequency quadrupole accelerator (RFQ) and an IH-type drift tube linac (IH-DTL) with the end energy of 7 MeV/u for all ions; a foil stripper directly located behind these cavities produces fully stripped ions (see Figure 2). ...
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Citations
... The charge state of the ions thereby depends on the kinetic energy of the plasma electrons and the confinement time of the ions in the plasma. Contemporary ECR sources used at medical accelerators can produce sufficient currents of multiply charged carbon ions where usually +4 C is extracted (Drentje et al. 2008, Winkelmann et al. 2014. At the HIT facility, the partially stripped ions are fully stripped of their electrons by a stripping foil placed after the LINAC pre-accelerator. ...
Particle therapy exploits the highly localized depth dose profile of protons and light ions to deliver a high dose to the target while largely sparing surrounding healthy tissue. The steep dose gradient at the end of the ions range, known as the Bragg peak, however, also makes particle therapy sensitive to range uncertainties. In current clinical practice, a major cause of range uncertainties resides in the conversion of the treatment planning x-ray CT to the patient specific relative stopping power (RSP) map that is crucial for accurate treatment planning. By measuring the energy loss of particles after traversing the patient, particle imaging enables a more direct reconstruction of the RSP. In this thesis, different aspects towards the clinical implementation of particle imaging are investigated. First, a theoretical description of the point-spread function for different particle radiography algorithms is developed in order to explain observed limitations. A novel filtering technique to remove nuclear interaction events in particle imaging is proposed and high quality experimental helium ion CTs are demonstrated. First results from an experimental comparison between particle and x-ray CT modalities for RSP prediction in animal tissue samples are presented. Furthermore, a novel technique for intra-treatment helium ion imaging based on a mixed helium/carbon beam is explored with that relative range changes in the millimeter regime were observable. Finally, novel particle imaging detector designs are investigated. The thesis highlights the potential of helium ion imaging for pre- and intra-treatment image guidance in particle therapy.
... At HIT, all ion beams are generated in one of three electron cyclotron resonance ECR ion sources. Proton beams are generated from hydrogen gas; carbon and oxygen ions from carbon dioxide gas and helium ions from helium gas (Winkelmann et al. (2014)). ECR ion sources offer stable ion beams, reliable long term operation and are easily maintained (Tinschert et al. (2008)). ...
In 2011, stereotactic body radiotherapy was introduced for the treatment of hepatocellular carcinoma at the Heidelberg Ion-Beam Therapy Center (HIT). Initially, thirteen patients were treated, including the first patient treated using respiratory beam gating. This thesis presents the work flow and data acquisition for the treatment of moving organs. Based on the acquired patient data, simulated and reconstructed 4D dose distributions are now available. Simulations of 4D dose distributions require precise knowledge of the organ motion and accelerator timing. To improve the prediction, the properties of the HIT synchrotron cycle were investigated, revealing energy-dependent and stochastic aspects and day-to-day beam intensity fluctuations. A simulation was implemented based on a realistic model of the accelerator. The accuracy of calculated irradiation sequences was verified using treatment records. Experimental verification using a patient treatment plan was performed in a moving water phantom, where a total dose deviation of (1.0±7.3)% was determined. Since 2012, the HIT heavy-ion gantry offers new treatment options. In a treatment planning study, optimal plan geometries for the treatment of esophageal carcinoma were determined. Effects of intrafractional organ motion were accounted for in a quasi-static dose calculation. Results can potentially be used for margin and gating window definition.
... Work on improving EBISes for IBT applications was pursued through 1990-s in the group led by R. Becker [41,42]. The early experiments with EBIS for synchrotron injection were later continued [43,44] and recently reached a commissioning stage at HIT [45] where for example an emittance reduction by a factor of 9 compared to an ECRIS was demonstrated [46]. In parallel, EBIS injectors were also studied for alternative accelerator concepts such as cyclinac [18]. ...
In this work we analyze how advanced Electron Beam Ion Sources (EBIS) can facilitate the progress of carbon therapy facilities. We will demonstrate that advanced ion sources enable operation of 2-nd generation ion beam therapy (IBT) accelerators. These new accelerator concepts with designs dedicated to IBT provide beams better suited for therapy and, are more cost efficient than contemporary IBT facilities. We will give a sort overview of the existing new IBT concepts and focus on those where ion source technology is the limiting factor. We will analyse whether this limitation can be overcome in the near future thanks to ongoing EBIS development.
