A5000207876- Atomic and Molecular Physics
- Radiation Therapy and Dosimetry
- Radiation Detection and Scintillator Technologies
- Quantum Chromodynamics and Particle Interactions
- Nuclear Physics and Applications
- Medical Imaging Techniques and Applications
- Nuclear physics research studies
- X-ray Spectroscopy and Fluorescence Analysis
- Advanced Radiotherapy Techniques
- Particle Detector Development and Performance
- Radiomics and Machine Learning in Medical Imaging
- Particle physics theoretical and experimental studies
- Advanced Chemical Physics Studies
- High-Energy Particle Collisions Research
- Muon and positron interactions and applications
- Advanced X-ray and CT Imaging
- Quantum, superfluid, helium dynamics
- Mass Spectrometry Techniques and Applications
- Scientific Research and Discoveries
- Radiation Effects in Electronics
- Electron and X-Ray Spectroscopy Techniques
- Particle accelerators and beam dynamics
- Ion-surface interactions and analysis
- Scientific Measurement and Uncertainty Evaluation
- Particle Accelerators and Free-Electron Lasers
TU Wien
2003-2024
Stefan Meyer Institute for Subatomic Physics
2009-2022
Austrian Academy of Sciences
2010-2022
Medical University of Vienna
2011-2017
General Electric (Austria)
2002
Abstract The hadronic width of the ground state pionic hydrogen has been redetermined by X-ray spectroscopy to be $$\varGamma ^{\pi \mathrm {H}}_{1s}=(856\,\pm \,16_\mathrm{stat}\,\pm \,22_\mathrm{sys})$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:msubsup> <mml:mi>Γ</mml:mi> <mml:mn>1</mml:mn> <mml:mi>s</mml:mi> </mml:mrow> <mml:mi>π</mml:mi> <mml:mi>H</mml:mi> </mml:msubsup> <mml:mo>=</mml:mo> <mml:mo>(</mml:mo> <mml:mn>856</mml:mn> <mml:mspace />...
The almost identical charge-to-mass ratios of fully ionized helium-4 and carbon-12 ions enable simultaneous acceleration in hadron therapy synchrotrons. At the same energy per mass, helium exhibit a stopping range approximately three times greater than carbon ions. They can therefore be exploited for online verification downstream patient during ion beam irradiation. One possibility creating this mixed is accelerating two species sequentially through LINAC subsequently "mixing" them at...
With the newly gained interest in time of flight method for positron emission tomography (TOF-PET), many options pushing resolution to its borders have been investigated. As one these exploitation Cherenkov effect has proposed, since it allows bypass scintillation process and therefore provides almost instantaneous response incident 511keV annihilation photons. Our simulation studies on yield photons, their arrival rate at photon detector angular distribution reveal a significant influence...
To gather information on clinical operations, quality control (QC) standards and adoption of guidelines for FDG-PET/CT imaging in Austrian PET/CT centres.A written survey composed 68 questions related to A) centre installation, B) standard protocol parameters oncology patients, C) QC procedures was conducted between November December 2013 among all centres. In addition, a NEMA-NU2 2012 image phantom test performed using whole-body settings systems with lesion-to-background ratio 4. Recovery...
Summary With the increasing use of functional imaging in modern radiotherapy (RT) and envisaged automated integration PET into target definition, need for reliable quantification is growing. Reconstruction algorithms new scanners employ pointspread-function (PSF) based resolution recovery, however, their impact on still requires thorough investigation. Patients, material, methods: Measurements were performed a Siemens PET/CT using an IEC phantom filled with varying activity. Data...
Abstract Objective. For dose calculations in ion beam therapy, it is vital to accurately determine the relative stopping power (RSP) distribution within treatment volume. A suitable imaging modality achieve required RSP accuracy proton computed tomography (pCT), which usually uses a tracking system and separate residual energy (or range) detector directly measure distribution. This work investigates potential of novel pCT based on single technology, namely low gain avalanche detectors...
To assess the influence of reconstruction algorithms for positron emission tomography (PET) based volume quantification. The specifically detected activity in threshold defined was investigated different as a function size and signal to background ratio (SBR), especially volumes smaller than 1ml. Special attention given Siemens specific iterative algorithm TrueX.Measurements were performed with modified in-house produced IEC body phantom on Biograph 64 True Point PET/CT scanner (Siemens,...
Purpose: To develop a flexible pencil beam algorithm for helium ion therapy. Dose distributions were calculated using the newly developed and validated Monte Carlo (MC) methods. Methods: The was based on established theory of fluence weighted elemental (PB) kernels. Using new real‐time splitting approach, minimization routine selects optimal shape each sub‐beam. depositions along path determined look‐up table (LUT). Data LUT generation derived from MC simulations in water GATE 6.1. For...
The aim of this study was to evaluate (18)F-fluoroethylcholine PET/CT as a metabolic imaging technique for the assessment treatment response (90)Y radioembolization in patients with locally advanced hepatocellular carcinoma (HCC).Thirty-four HCC undergoing 78 scans were identified study. Patients initial or follow-up metastastic disease (n = 9) excluded at time point metastatic occurrence well negative α-fetoprotein (AFP; n 1), resulting 24 and 57 that eligible. All scheduled underwent 1...
Inspection and quantitative validation of tomographic imaging properties SPECT systems, i.e., spatial resolution, contrast, inhomogeneity must be performed in regular intervals. Typically, the modular Jaszczak phantom is used for that purpose, as it offers possibility to investigate all three system with a single measurement. The interpretation measurement visually, thus, being insensitive subtle changes performance. To overcome this limitation, fully-automated software objective analysis...
Photodetectors with excellent time resolution are becoming increasingly important in many applications medicine, high energy- and nuclear physics applications, biology, material science. Silicon photomultipliers (SiPM) a novel class of solid-state photodetectors good timing properties. While the analog SiPMs has been analyzed by groups, digital photon counter (DPC) developed Philips not yet fully characterised. Here, capabilities DPC studied using femtosecond laser. The is determined for...
An unusual but effective way to determine at threshold the $d\ensuremath{\pi}\ensuremath{\leftrightarrow}NN$ transition strength $\ensuremath{\alpha}$ is exploit hadronic ground-state broadening ${\ensuremath{\Gamma}}_{1s}$ in pionic deuterium, accessible by x-ray spectroscopy. The dominated true absorption channel $d{\ensuremath{\pi}}^{\ensuremath{-}}\ensuremath{\rightarrow}nn$, which related $s$-wave pion production $pp\ensuremath{\rightarrow}d{\ensuremath{\pi}}^{+}$ charge symmetry and...
The $(3p\ensuremath{-}1s)$ x-ray transition to the muonic hydrogen ground state was measured with a high-resolution crystal spectrometer. A Doppler effect broadening of line established which could be attributed different Coulomb deexcitation steps preceding transition. assumption statistical population hyperfine levels directly confirmed by experiment, and values for splitting can reported. results allow decisive test advanced cascade model calculations establish method extract fundamental...
A set of 14 high-accuracy x-ray transition energies in the 2.4--3.1 keV range is presented, which can be used as standards. They were measured two- to four-electron sulfur, chlorine, and argon ions produced an electron-cyclotron resonance ion source, using a single spherically bent crystal spectrometer. The results include first measurement six transitions improve accuracy other experimental values. These measurements considerably extend reported for highly charged ions. Their relative...
Abstract Objective. Ion computed tomography (iCT) is an imaging modality for the direct determination of relative stopping power (RSP) distribution within a patient’s body. Usually, this done by estimating path and energy loss ions traversing scanned volume utilising tracking system separate residual detector. This study, on other hand, introduces first experimental study novel iCT approach based time-of-flight (TOF) measurements, so-called Sandwich TOF-iCT concept, which in contrast to any...
We present a new measurement on X-ray spectroscopy of multicharged argon, chlorine and sulfur obtained with the Electron Cyclotron Resonance Ion Trap installed at Paul Scherrer Institut (Villigen, Switzerland). For this purpose, we used crystal spectrometer spherically bent having an energy resolution about 0.4 eV. High intensity Kα spectra were from ions one 1s hole ranging almost neutral to heliumlike charge states. In particular observed 1s2s3S1 → 1s2 1S0 M1 1s2p3P2 M2 transitions in...