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Author Torres-Espallardo, I.; Diblen, F.; Rohling, H.; Solevi, P.; Gillam, J.; Watts, D.; Espana, S.; Vandenberghe, S.; Fiedler, F.; Rafecas, M.
Title Evaluation of resistive-plate-chamber-based TOF-PET applied to in-beam particle therapy monitoring Type Journal Article
Year 2015 Publication Physics in Medicine and Biology Abbreviated Journal Phys. Med. Biol.
Volume 60 Issue (down) 9 Pages N187-N208
Keywords PET; in-beam; RPC; particle therapy; TOF; range deviation; partial-ring
Abstract Particle therapy is a highly conformal radiotherapy technique which reduces the dose deposited to the surrounding normal tissues. In order to fully exploit its advantages, treatment monitoring is necessary to minimize uncertainties related to the dose delivery. Up to now, the only clinically feasible technique for the monitoring of therapeutic irradiation with particle beams is Positron Emission Tomography (PET). In this work we have compared a Resistive Plate Chamber (RPC)-based PET scanner with a scintillation-crystal-based PET scanner for this application. In general, the main advantages of the RPC-PET system are its excellent timing resolution, low cost, and the possibility of building large area systems. We simulated a partial-ring scannerbeam monitoring, which has an intrinsically low positron yield compared to diagnostic PET. In addition, for in-beam PET there is a further data loss due to the partial ring configuration. In order to improve the performance of the RPC-based scanner, an improved version of the RPC detector (modifying the thickness of the gas and glass layers), providing a larger sensitivity, has been simulated and compared with an axially extended version of the crystal-based device. The improved version of the RPC shows better performance than the prototype, but the extended version of the crystal-based PET outperforms all other options. based on an RPC prototype under construction within the Fondazione per Adroterapia Oncologica (TERA). For comparison with the crystal-based PET scanner we have chosen the geometry of a commercially available PET scanner, the Philips Gemini TF. The coincidence time resolution used in the simulations takes into account the current achievable values as well as expected improvements of both technologies. Several scenarios (including patient data) have been simulated to evaluate the performance of different scanners. Initial results have shown that the low sensitivity of the RPC hampers its application to hadron
Address [Torres-Espallardo, I.; Solevi, P.; Gillam, J.; Rafecas, M.] UV, CSIC, Inst Fis Corpuscular IFIC, E-46071 Valencia, Spain, Email: irene.torres@uv.es
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9155 ISBN Medium
Area Expedition Conference
Notes WOS:000354104700003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2227
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Author Marco-Hernandez, R.; Bau, M.; Ferrari, M.; Ferrari, V.; Pedersen, F.; Soby, L.
Title A Low-Noise Charge Amplifier for the ELENA Trajectory, Orbit, and Intensity Measurement System Type Journal Article
Year 2017 Publication IEEE Transactions on Nuclear Science Abbreviated Journal IEEE Trans. Nucl. Sci.
Volume 64 Issue (down) 9 Pages 2465-2473
Keywords Beam position monitor (BPM); charge sensitive amplifier; instrumentation for accelerators; low-noise amplifier; particle accelerators; printed circuits
Abstract A low-noise head amplifier has been developed for the extra low energy antiproton ring beam trajectory, orbit, and intensity measurement system at CERN. This system is based on 24 double-electrode electrostatic beam position monitors installed around the ring. A head amplifier is placed close to each beam position monitor to amplify the electrode signals and generate a difference and a sum signal. These signals are sent to the digital acquisition system, about 50 m away from the ring, where they are digitized and further processed. The beam position can be measured by dividing the difference signal by the sum signal while the sum signal gives information relative to the beam intensity. The head amplifier consists of two discrete charge preamplifiers with junction field effect transistor (JFET) inputs, a sum and a difference stage, and two cable drivers. Special attention has been paid to the amplifier printed circuit board design to minimize the parasitic capacitances and inductances at the charge amplifier stages to meet the gain and noise requirements. The measurements carried out on the head amplifier showed a gain of 40.5 and 46.5 dB for the sum and difference outputs with a bandwidth from 200 Hz to 75 MHz and an input voltage noise density lower than 400 pV/v Hz. Twenty head amplifiers have been already installed in the ring and they have been used to detect the first beam signals during the first commissioning stage in November 2016.
Address [Marco-Hernandez, Ricardo; Pedersen, Flemming; Soby, Lars] CERN, CH-1217 Meyrin, Switzerland, Email: rmarco@ific.uv.es
Corporate Author Thesis
Publisher Ieee-Inst Electrical Electronics Engineers Inc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0018-9499 ISBN Medium
Area Expedition Conference
Notes WOS:000411029500002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3298
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Author Candela-Juan, C.; Vijande, J.; Garcia-Martinez, T.; Niatsetski, Y.; Nauta, G.; Schuurman, J.; Ouhib, Z.; Ballester, F.; Perez-Calatayud, J.
Title Comparison and uncertainty evaluation of different calibration protocols and ionization chambers for low-energy surface brachytherapy dosimetry Type Journal Article
Year 2015 Publication Medical Physics Abbreviated Journal Med. Phys.
Volume 42 Issue (down) 8 Pages 4954-4964
Keywords x-ray beams; electronic brachytherapy; surface applicators; dosimetry; uncertainty
Abstract Purpose: A surface electronic brachytherapy (EBT) device is in fact an x-ray source collimated with specific applicators. Low-energy (<100 kVp) x-ray beam dosimetry faces several challenges that need to be addressed. A number of calibration protocols have been published for x-ray beam dosimetry. The media in which measurements are performed are the fundamental difference between them. The aim of this study was to evaluate the surface dose rate of a low-energy x-ray source with small field applicators using different calibration standards and different small-volume ionization chambers, comparing the values and uncertainties of each methodology. Methods: The surface dose rate of the EBT unit Esteya (Elekta Brachytherapy, The Netherlands), a 69.5 kVp x-ray source with applicators of 10, 15, 20, 25, and 30 mm diameter, was evaluated using the AAPM TG-61 (based on air kerma) and International Atomic Energy Agency (IAEA) TRS-398 (based on absorbed dose to water) dosimetry protocols for low-energy photon beams. A plane parallel T34013 ionization chamber (PTW Freiburg, Germany) calibrated in terms of both absorbed dose to water and air kerma was used to compare the two dosimetry protocols. Another PTW chamber of the same model was used to evaluate the reproducibility between these chambers. Measurements were also performed with two different Exradin A20 (Standard Imaging, Inc., Middleton, WI) chambers calibrated in terms of air kerma. Results: Differences between surface dose rates measured in air and in water using the T34013 chamber range from 1.6% to 3.3%. No field size dependence has been observed. Differences are below 3.7% when measurements with the A20 and the T34013 chambers calibrated in air are compared. Estimated uncertainty (with coverage factor k = 1) for the T34013 chamber calibrated in water is 2.2%-2.4%, whereas it increases to 2.5% and 2.7% for the A20 and T34013 chambers calibrated in air, respectively. The output factors, measured with the PTW chambers, differ by less than 1.1% for any applicator size when compared to the output factors that were measured with the A20 chamber. Conclusions: Measurements using both dosimetric protocols are consistent, once the overall uncertainties are considered. There is also consistency between measurements performed with both chambers calibrated in air. Both the T34013 and A20 chambers have negligible stem effect. Any x-ray surface brachytherapy system, including Esteya, can be characterized using either one of these calibration protocols and ionization chambers. Having less correction factors, lower uncertainty, and based on measurements, performed in closer to clinical conditions, the TRS-398 protocol seems to be the preferred option.
Address [Candela-Juan, C.; Perez-Calatayud, J.] La Fe Univ, Dept Radiat Oncol, Valencia 46026, Spain, Email: ccanjuan@gmail.com
Corporate Author Thesis
Publisher Amer Assoc Physicists Medicine Amer Inst Physics Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0094-2405 ISBN Medium
Area Expedition Conference
Notes WOS:000358933000051 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2323
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Author Piersanti, L.; Bellini, F.; Bini, F.; Collamati, F.; De Lucia, E.; Durante, M.; Faccini, R.; Ferroni, F.; Fiore, S.; Iarocci, E.; La Tessa, C.; Marafini, M.; Mattei, I.; Patera, V.; Ortega, P.G.; Sarti, A.; Schuy, C.; Sciubba, A.; Vanstalle, M.; Voena, C.
Title Measurement of charged particle yields from PMMA irradiated by a 220 MeV/u C-12 beam Type Journal Article
Year 2014 Publication Physics in Medicine and Biology Abbreviated Journal Phys. Med. Biol.
Volume 59 Issue (down) 7 Pages 1857-1872
Keywords drift chamber; LYSO; hadrontherapy; carbon ion beam; dose monitoring
Abstract The radiation used in hadrontherapy treatments interacts with the patient body producing secondary particles, either neutral or charged, that can be used for dose and Bragg peak monitoring and to provide a fast feedback on the treatment plans. Recent results obtained from the authors on simplified setups (mono-energetic primary beams interacting with homogeneous tissue like target) have already indicated the correlation that exists between the flux of these secondaries coming from the target (e.g. protons and photons) and the position of the primary beam Bragg peak. In this paper, the measurements of charged particle fluxes produced by the interaction of a 220 MeV/u carbon ion beam at GSI, Darmstadt, with a polymethyl methacrylate target are reported. The emission region of protons (p), deuterons (d) and tritons (t) has been characterized using a drift chamber while the particle time-of-flight, used to compute the kinetic energy spectra, was measured with a LYSO scintillator.The energy released in the LYSO crystal was used for particle identification purposes. The measurements were repeated with the setup at 60 degrees and 90 degrees with respect to the primary beam direction. The accuracy on the fragments emission profile reconstruction and its relationship with the Bragg peak position have been studied. Based on the acquired experimental evidence, a method to monitor the dose profile and the position of the Bragg peak inside the target is proposed.
Address [Piersanti, L.; De Lucia, E.; Iarocci, E.; Mattei, I.; Sarti, A.] Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy, Email: vincenzo.patera@lnf.infn.it
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9155 ISBN Medium
Area Expedition Conference
Notes WOS:000333186200020 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1735
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Author NEXT Collaboration (Navarro, K.E. et al); Carcel, S.; Carrion, J.V.; Lopez, F.; Lopez-March, N.; Martin-Albo, J.; Muñoz Vidal, J.; Novella, P.; Querol, M.; Romo-Luque, C.; Sorel, M.; Uson, A.
Title A compact dication source for Ba2+ tagging and heavy metal ion sensor development Type Journal Article
Year 2023 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.
Volume 18 Issue (down) 7 Pages P07044 - 19pp
Keywords Beam Optics; Heavy-ion detectors; Ion identification systems; Ion sources (positive ions; negative ions; electron cyclotron resonance (ECR); electron beam (EBIS))
Abstract We present a tunable metal ion beam that delivers controllable ion currents in the picoamp range for testing of dry-phase ion sensors. Ion beams are formed by sequential atomic evaporation and single or multiple electron impact ionization, followed by acceleration into a sensing region. Controllability of the ionic charge state is achieved through tuning of electrode potentials that influence the retention time in the ionization region. Barium, lead, and cadmium samples have been used to test the system, with ion currents identified and quantified using a quadrupole mass analyzer. Realization of a clean Ba2+ ion beam within a bench-top system represents an important technical advance toward the development and characterization of barium tagging systems for neutrinoless double beta decay searches in xenon gas. This system also provides a testbed for investigation of novel ion sensing methodologies for environmental assay applications, with dication beams of Pb2+ and Cd2+ also demonstrated for this purpose.
Address [Navarro, K. E.; Baeza-Rubio, J.; Giri, S.; Jones, B. J. P.; Nygren, D. R.; Samaniego, F. J.; Stogsdill, K.; Tiscareno, M. R.; Byrnes, N.; Dey, E.; Mistry, K.; Parmaksiz, I.] Univ Texas Arlington, Dept Phys, Arlington, TX 76019 USA, Email: karen.navarro@uta.edu
Corporate Author Thesis
Publisher IOP Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1748-0221 ISBN Medium
Area Expedition Conference
Notes WOS:001106703500002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5860
Permanent link to this record