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Author Valdes-Cortez, C.; Ballester, F.; Vijande, J.; Gimenez, V.; Gimenez-Alventosa, V.; Perez-Calatayud, J.; Niatsetski, Y.; Andreo, P.
Title Depth-dose measurement corrections for the surface electronic brachytherapy beams of an Esteya(R) unit: a Monte Carlo study Type Journal Article
Year 2020 Publication Physics in Medicine and Biology Abbreviated Journal Phys. Med. Biol.
Volume 65 Issue 24 Pages 245026 - 12pp
Keywords electronic brachytherapy; eBT; dosimetry; ionization chamber; Monte Carlo
Abstract Three different correction factors for measurements with the parallel-plate ionization chamber PTW T34013 on the Esteya electronic brachytherapy unit have been investigated. This chamber type is recommended by AAPM TG-253 for depth-dose measurements in the 69.5 kV x-ray beam generated by the Esteya unit. Monte Carlo simulations using the PENELOPE-2018 system were performed to determine the absorbed dose deposited in water and in the chamber sensitive volume at different depths with a Type A uncertainty smaller than 0.1%. Chamber-to-chamber differences have been explored performing measurements using three different chambers. The range of conical applicators available, from 10 to 30 mm in diameter, has been explored. Using a depth-independent global chamber perturbation correction factor without a shift of the effective point of measurement yielded differences between the absorbed dose to water and the corrected absorbed dose in the sensitive volume of the chamber of up to 1% and 0.6% for the 10 mm and 30 mm applicators, respectively. Calculations using a depth-dependent perturbation factor, including or excluding a shift of the effective point of measurement, resulted in depth-dose differences of about +/- 0.5% or less for both applicators. The smallest depth-dose differences were obtained when a shift of the effective point of measurement was implemented, being displaced 0.4 mm towards the center of the sensitive volume of the chamber. The correction factors were obtained with combined uncertainties of 0.4% (k = 2). Uncertainties due to chamber-to-chamber differences are found to be lower than 2%. The results emphasize the relevance of carrying out detailed Monte Carlo studies for each electronic brachytherapy device and ionization chamber used for its dosimetry.
Address (down) [Valdes-Cortez, Christian; Ballester, Facundo; Vijande, Javier] Univ Valencia UV, Dept Fis Atom Mol & Nucl, Burjassot, Spain, Email: cvalcort@gmail.com
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:000618031500001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4708
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Author Ullan, M.; Benitez, V.; Quirion, D.; Zabala, M.; Pellegrini, G.; Lozano, M.; Lacasta, C.; Soldevila, U.; Garcia, C.; Fadeyev, V.; Wortman, J.; DeFilippis, J.; Shumko, M.; Grillo, A.A.; Sadrozinski, H.F.W.
Title Low-resistance strip sensors for beam-loss event protection Type Journal Article
Year 2014 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A
Volume 765 Issue Pages 252-257
Keywords Silicon radiation detectors; Strip sensors; Punch through protection; Beam loss; HL-LHC; ATLAS Upgrade
Abstract AC coupled silicon strip sensors can be damaged in case of a beam loss due to the possibility of a large charge accumulation in the bulk, developing very high voltages across the coupling capacitors which can destroy them. Punch-through structures are currently used to avoid this problem helping to evacuate the accumulated charge as large voltages are developing. Nevertheless, previous experiments, performed with laser pulses, have shown that these structures can become ineffective in relatively long strips. The large value of the implant resistance can effectively isolate the “far” end of the strip from the punchthrough structure leading to large voltages. We present here our developments to fabricate lowresistance strip sensors to avoid this problem. The deposition of a conducting material in contact with the implants drastically reduces the strip resistance, assuring the effectiveness of the punch-through structures. First devices have been fabricated with this new technology. Initial results with laser tests show the expected reduction in peak voltages on the low resistivity implants. Other aspects of the sensor performance, including the signal formation, are not affected by the new technology.
Address (down) [Ullan, M.; Benitez, V.; Quirion, D.; Zabala, M.; Pellegrini, G.; Lozano, M.] CSIC, Ctr Nacl Microelect IMB CNM, Barcelona 08193, Spain, Email: Miguel.Ullan@imb-cnm.csic.es
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0168-9002 ISBN Medium
Area Expedition Conference
Notes WOS:000344621000048 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2003
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Author ANTARES Collaboration (Albert, A. et al); Barrios-Marti, J.; Coleiro, A.; Colomer, M.; Hernandez-Rey, J.J.; Illuminati, G.; Lotze, M.; Zornoza, J.D.; Zuñiga, J.
Title The search for high-energy neutrinos coincident with fast radio bursts with the ANTARES neutrino telescope Type Journal Article
Year 2019 Publication Monthly Notices of the Royal Astronomical Society Abbreviated Journal Mon. Not. Roy. Astron. Soc.
Volume 482 Issue 1 Pages 184-193
Keywords acceleration of particles; neutrinos; astroparticle physics; radio continuum: transients; methods: data analysis
Abstract In the past decade, a new class of bright transient radio sources with millisecond duration has been discovered. The origin of these so-called fast radio bursts (FRBs) is still a mystery, despite the growing observational efforts made by various multiwavelength and multimessenger facilities. To date, many models have been proposed to explain FRBs, but neither the progenitors nor the radiative and the particle acceleration processes at work have been clearly identified. In this paper, we assess whether hadronic processes may occur in the vicinity of the FRB source. If they do, FRBs may contribute to the high-energy cosmic-ray and neutrino fluxes. A search for these hadronic signatures was carried out using the ANTARES neutrino telescope. The analysis consists in looking for high-energy neutrinos, in the TeV-PeV regime, that are spatially and temporally coincident with the detected FRBs. Most of the FRBs discovered in the period 2013-2017 were in the field of view of the ANTARES detector, which is sensitive mostly to events originating from the Southern hemisphere. From this period, 12 FRBs were selected and no coincident neutrino candidate was observed. Upper limits on the per-burst neutrino fluence were derived using a power-law spectrum, dN/DE nu proportional to E-nu(-gamma), for the incoming neutrino flux, assuming spectral indexes gamma = 1.0, 2.0, 2.5. Finally, the neutrino energy was constrained by computing the total energy radiated in neutrinos, assuming different distances for the FRBs. Constraints on the neutrino fluence and on the energy released were derived from the associated null results.
Address (down) [Turpin, D.] Chinese Acad Sci, Natl Astron Observ, Key Lab Space Astron & Technol, Beijing 100101, Peoples R China, Email: dornic@cppm.in2p3.fr;
Corporate Author Thesis
Publisher Oxford Univ Press Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0035-8711 ISBN Medium
Area Expedition Conference
Notes WOS:000454575300014 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3860
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Author Trotta, R.; Johannesson, G.; Moskalenko, I.V.; Porter, T.A.; Ruiz de Austri, R.; Strong, A.W.
Title Constraints on Cosmic-Ray Propagation Models from a Global Bayesian Analysis Type Journal Article
Year 2011 Publication Astrophysical Journal Abbreviated Journal Astrophys. J.
Volume 729 Issue 2 Pages 106 - 16pp
Keywords astroparticle physics; cosmic rays; diffusion; Galaxy: general; ISM: general; methods: statistical
Abstract Research in many areas of modern physics such as, e. g., indirect searches for dark matter and particle acceleration in supernova remnant shocks rely heavily on studies of cosmic rays (CRs) and associated diffuse emissions (radio, microwave, X-rays, gamma-rays). While very detailed numerical models of CR propagation exist, a quantitative statistical analysis of such models has been so far hampered by the large computational effort that those models require. Although statistical analyses have been carried out before using semi-analytical models (where the computation is much faster), the evaluation of the results obtained from such models is difficult, as they necessarily suffer from many simplifying assumptions. The main objective of this paper is to present a working method for a full Bayesian parameter estimation for a numerical CR propagation model. For this study, we use the GALPROP code, the most advanced of its kind, which uses astrophysical information, and nuclear and particle data as inputs to self-consistently predict CRs, gamma-rays, synchrotron, and other observables. We demonstrate that a full Bayesian analysis is possible using nested sampling and Markov Chain Monte Carlo methods (implemented in the SuperBayeS code) despite the heavy computational demands of a numerical propagation code. The best-fit values of parameters found in this analysis are in agreement with previous, significantly simpler, studies also based on GALPROP.
Address (down) [Trotta, R.] Univ London Imperial Coll Sci Technol & Med, Astrophys Grp, Blackett Lab, London SW7 2AZ, England
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 0004-637x ISBN Medium
Area Expedition Conference
Notes ISI:000288608700029 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 541
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Author Trbojevich, R.A.; Fernandez, A.; Watanabe, F.; Mustafa, T.; Bryant, M.S.
Title Comparative study of silver nanoparticle permeation using Side-Bi-Side and Franz diffusion cells Type Journal Article
Year 2016 Publication Journal of Nanoparticle Research Abbreviated Journal J. Nanopart. Res.
Volume 18 Issue 3 Pages 55 - 12pp
Keywords Membranes; Silver nanoparticles; Diffusion cells; Food packaging; Permeation; Environmental and health effects
Abstract Better understanding the mechanisms of nanoparticle permeation through membranes and packaging polymers has important implications for the evaluation of drug transdermal uptake, in food safety and the environmental implications of nanotechnology. In this study, permeation of 21 nm diameter silver nanoparticles (AgNPs) was tested using Side-Bi-Side and Franz static diffusion cells through hydrophilic 0.1 and 0.05 lm pore diameter 125 μm thick synthetic cellulose membranes, and 16 and 120 μm thick low-density polyethylene (LDPE) films. Experiments performed with LDPE films discarded permeation of AgNPs or Ag ions over the investigated time-frame in both diffusion systems. But controlled release of AgNPs has been quantified using semipermeable hydrophilic membranes. The permeation followed a quasi-linear time-dependent model during the experimental time-frame, which represents surface reaction-limited permeation. Diffusive flux, diffusion coefficients, and membrane permeability were determined as a function of pore size and diffusion model. Concentration gradient and pore size were key to understand mass transfer phenomena in the diffusion systems.
Address (down) [Trbojevich, Raul A.; Bryant, Matthew S.] US FDA, Div Biochem Toxicol, Natl Ctr Toxicol Res, 3900 NCTR Rd, Jefferson, AR 72079 USA, Email: velifdez@ific.uv.es
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1388-0764 ISBN Medium
Area Expedition Conference
Notes WOS:000387044400002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2849
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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 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 (down) [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 Martinez Torres, A.; Khemchandani, K.P.; Jido, D.; Kanada-En'yo, Y.; Oset, E.
Title Three-body hadron systems with strangeness Type Journal Article
Year 2013 Publication Nuclear Physics A Abbreviated Journal Nucl. Phys. A
Volume 914 Issue Pages 280-288
Keywords Unitary chiral theories; Few-body systems
Abstract Recently, many efforts are being put in studying three-hadron systems made of mesons and baryons and interesting results are being found. In this talk, we summarize the main features of the formalism used to study such three hadron systems with strangeness S = -1, 0 within a framework built on the basis of unitary chiral theories and solution of the Faddeev equations. In particular, we present the results obtained for the pi(K) over barN, K (K) over barN and KK (K) over bar systems and their respective coupled channels. In the first case, we find four Sigma's and two A's with spin-parity J(P) = 1/2(+), in the 1500-1800 MeV region, as two meson-one baryon s-wave resonances. In the second case, a 1/2(+) N* around 1900 MeV is found. For the last one a kaon close to 1420 MeV is formed, which can be identified with K(1460).
Address (down) [Torres, A. Martinez; Khemchandani, K. P.] Univ Sao Paulo, Inst Fis, BR-05314970 Sao Paulo, Brazil, Email: amartine@if.usp.br;
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0375-9474 ISBN Medium
Area Expedition Conference
Notes WOS:000324847700036 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1596
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Author BRIKEN Collaboration (Tolosa-Delgado, A. et al); Agramunt, J.; Tain, J.L.; Algora, A.; Domingo-Pardo, C.; Morales, A.I.; Rubio, B.
Title Commissioning of the BRIKEN detector for the measurement of very exotic beta-delayed neutron emitters Type Journal Article
Year 2019 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A
Volume 925 Issue Pages 133-147
Keywords Beta-delayed neutrons; Neutron and beta counters; Analysis methodology; Background correction
Abstract A new detection system has been installed at the RIKEN Nishina Center (Japan) to investigate decay properties of very neutron-rich nuclei. The setup consists of three main parts: a moderated neutron counter, a detection system sensitive to the implantation and decay of radioactive ions, and gamma-ray detectors. We describe here the setup, the commissioning experiment and some selected results demonstrating its performance for the measurement of half-lives and beta-delayed neutron emission probabilities. The methodology followed in the analysis of the data is described in detail. Particular emphasis is placed on the correction of the accidental neutron background.
Address (down) [Tolosa-Delgado, A.; Agramunt, J.; Tain, J. L.; Algora, A.; Domingo-Pardo, C.; Morales, A., I; Rubio, B.] CSIC, Inst Fis Corpuscular, E-46980 Paterna, Spain, Email: tain@ific.uv.es
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0168-9002 ISBN Medium
Area Expedition Conference
Notes WOS:000460539400018 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3939
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Author n_TOF Collaboration (Tarrio, D. et al); Domingo-Pardo, C.; Giubrone, G.; Tain, J.L.
Title Measurement of the angular distribution of fission fragments using a PPAC assembly at CERN n_TOF Type Journal Article
Year 2014 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A
Volume 743 Issue Pages 79-85
Keywords Fission; Neutron; Anisotropy; Angular distribution; Th-232; Gas detectors
Abstract A fission reaction chamber based on Parallel Plate Avalanche Counters (PPACs) was built for measuring angular distributions of fragments emitted in neutron-induced fission of actinides at the neutron beam available at the Neutron Time-Of-Flight (n_TOF) facility at CERN. The detectors and the samples were tilted 45 degrees with respect to the neutron beam direction to cover all the possible values of the emission angle of the fission fragments. The main features of this setup are discussed and results on the fission fragment angular distribution are provided for the Th-232(n,f) reaction around the fission threshold. The results are compared with the available data in the literature, demonstrating the good capabilities of this setup.
Address (down) [Tarrio, D.; Duran, I.; Paradela, C.; Caamano, M.] Univ Santiago de Compostela, Santiago De Compostela, Spain, Email: dtarriov@gmail.com
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0168-9002 ISBN Medium
Area Expedition Conference
Notes WOS:000334005000011 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1746
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Author BRIKEN Collaboration (Tarifeño-Saldivia, A. et al); Tain, J.L.; Domingo-Pardo, C.; Agramunt, J.; Algora, A.; Morales, A.I.; Rubio, B.; Tolosa, A.
Title Conceptual design of a hybrid neutron-gamma detector for study of beta-delayed neutrons at the RIB facility of RIKEN Type Journal Article
Year 2017 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.
Volume 12 Issue Pages P04006 - 22pp
Keywords Detector modelling and simulations I (interaction of radiation with matter, interaction; of photons with matter, interaction of hadrons with matter, etc); Instrumentation for radioactive beams (fragmentation devices; fragment and isotope, separators incl. ISOL; isobar separators; ion and atom traps; weak-beam diagnostics; radioactive-beam ion sources); Neutron detectors (cold, thermal, fast neutrons)
Abstract BRIKEN is a complex detection system to be installed at the RIB-facility of the RIKEN Nishina Center. It is aimed at the detection of heavy-ion implants, β-particles, γ-rays and β-delayed neutrons. The whole detection setup involves the Advanced Implantation Detection Array (AIDA), two HPGe Clover detectors and a large set of 166 counters of 3He embedded in a high-density polyethylene matrix. This article reports on a novel methodology developed for the conceptual design and optimisation of the 3He-tubes array, aiming at the best possible performance in terms of neutron detection. The algorithm is based on a geometric representation of two selected parameters of merit, namely, average neutron detection efficiency and efficiency flatness, as a function of a reduced number of geometric variables. The response of the detection system itself, for each configuration, is obtained from a systematic MC-simulation implemented realistically in Geant4. This approach has been found to be particularly useful. On the one hand, due to the different types and large number of 3He-tubes involved and, on the other hand, due to the additional constraints introduced by the ancillary detectors for charged particles and gamma-rays. Empowered by the robustness of the algorithm, we have been able to design a versatile detection system, which can be easily re-arranged into a compact mode in order to maximize the neutron detection performance, at the cost of the gamma-ray sensitivity. In summary, we have designed a system which shows, for neutron energies up to 1(5) MeV, a rather flat and high average efficiency of 68.6%(64%) and 75.7%(71%) for the hybrid and compact modes, respectively. The performance of the BRIKEN system has been also quantified realistically by means of MC-simulations made with different neutron energy distributions.
Address (down) [Tarifeno-Saldivia, A.] UPC, Barcelona, Spain, Email: ariel.esteban.tarifeno@upc.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:000405067800006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3209
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