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Author de Azcarraga, J.A.; Izquierdo, J.M.
Title k-Leibniz algebras from lower order ones: From Lie triple to Lie l-ple systems Type Journal Article
Year 2013 Publication Journal of Mathematical Physics Abbreviated Journal J. Math. Phys.
Volume (up) 54 Issue 9 Pages 093510 - 14pp
Keywords
Abstract Two types of higher order Lie l-ple systems are introduced in this paper. They are defined by brackets with l > 3 arguments satisfying certain conditions, and generalize the well-known Lie triple systems. One of the generalizations uses a construction that allows us to associate a (2n – 3)-Leibniz algebra pound with a metric n-Leibniz algebra () pound over tilde by using a 2(n – 1)-linear Kasymov trace form for () pound over tilde. Some specific types of k-Leibniz algebras, relevant in the construction, are introduced as well. Both higher order Lie l-ple generalizations reduce to the standard Lie triple systems for l = 3.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-2488 ISBN Medium
Area Expedition Conference
Notes WOS:000325407300032 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 1618
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Author Gillam, J.E.; Solevi, P.; Oliver, J.F.; Rafecas, M.
Title Simulated one-pass list-mode: an approach to on-the-fly system matrix calculation Type Journal Article
Year 2013 Publication Physics in Medicine and Biology Abbreviated Journal Phys. Med. Biol.
Volume (up) 58 Issue 7 Pages 2377-2394
Keywords
Abstract In the development of prototype systems for positron emission tomography a valid and robust image reconstruction algorithm is required. However, prototypes often employ novel detector and system geometries which may change rapidly under optimization. In addition, developing systems generally produce highly granular, or possibly continuous detection domains which require some level of on-the-fly calculation for retention of measurement precision. In this investigation a new method of on-the-fly system matrix calculation is proposed that provides advantages in application to such list-mode systems in terms of flexibility in system modeling. The new method is easily adaptable to complicated system geometries and available computational resources. Detection uncertainty models are used as random number generators to produce ensembles of possible photon trajectories at image reconstruction time for each datum in the measurement list. However, the result of this approach is that the system matrix elements change at each iteration in a non-repetitive manner. The resulting algorithm is considered the simulation of a one-pass list (SOPL) which is generated and the list traversed during image reconstruction. SOPL alters the system matrix in use at each iteration and so behavior within the maximum likelihood-expectation maximization algorithm was investigated. A two-pixel system and a small two dimensional imaging model are used to illustrate the process and quantify aspects of the algorithm. The two-dimensional imaging system showed that, while incurring a penalty in image resolution, in comparison to a non-random equal-computation counterpart, SOPL provides much enhanced noise properties. In addition, enhancement in system matrix quality is straightforward (by increasing the number of samples in the ensemble) so that the resolution penalty can be recovered when desired while retaining improvement in noise properties. Finally the approach is tested and validated against a standard (highly accurate) system matrix using experimental data from a prototype system-the AX-PET.
Address [Gillam, J. E.; Solevi, P.; Oliver, J. F.; Rafecas, M.] Univ Valencia, CSIC, IFIC, Inst Fis Corpuscular, Valencia, Spain, Email: john.gillam@ific.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:000316181300024 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 1370
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Author Robert, C.; Dedes, G.; Battistoni, G.; Bohlen, T.T.; Buvat, I.; Cerutti, F.; Chin, M.P.W.; Ferrari, A.; Gueth, P.; Kurz, C.; Lestand, L.; Mairani, A.; Montarou, G.; Nicolini, R.; Ortega, P.G.; Parodi, K.; Prezado, Y.; Sala, P.R.; Sarrut, D.; Testa, E.
Title Distributions of secondary particles in proton and carbon-ion therapy: a comparison between GATE/Geant4 and FLUKA Monte Carlo codes Type Journal Article
Year 2013 Publication Physics in Medicine and Biology Abbreviated Journal Phys. Med. Biol.
Volume (up) 58 Issue 9 Pages 2879-2899
Keywords
Abstract Monte Carlo simulations play a crucial role for in-vivo treatment monitoring based on PET and prompt gamma imaging in proton and carbon-ion therapies. The accuracy of the nuclear fragmentation models implemented in these codes might affect the quality of the treatment verification. In this paper, we investigate the nuclear models implemented in GATE/Geant4 and FLUKA by comparing the angular and energy distributions of secondary particles exiting a homogeneous target of PMMA. Comparison results were restricted to fragmentation of O-16 and C-12. Despite the very simple target and set-up, substantial discrepancies were observed between the two codes. For instance, the number of high energy (>1 MeV) prompt gammas exiting the target was about twice as large with GATE/Geant4 than with FLUKA both for proton and carbon ion beams. Such differences were not observed for the predicted annihilation photon production yields, for which ratios of 1.09 and 1.20 were obtained between GATE and FLUKA for the proton beam and the carbon ion beam, respectively. For neutrons and protons, discrepancies from 14% (exiting protons-carbon ion beam) to 57% (exiting neutrons-proton beam) have been identified in production yields as well as in the energy spectra for neutrons.
Address Univ Paris 07, IMNC, CNRS, UMR 8165, F-91406 Orsay, France, Email: robert@imnc.in2p3.fr
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:000317579900010 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1407
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Author Solevi, P. et al; Oliver, J.F.; Gillam, J.E.; Rafecas, M.
Title A Monte-Carlo based model of the AX-PET demonstrator and its experimental validation Type Journal Article
Year 2013 Publication Physics in Medicine and Biology Abbreviated Journal Phys. Med. Biol.
Volume (up) 58 Issue 16 Pages 5495-5510
Keywords
Abstract AX-PET is a novel PET detector based on axially oriented crystals and orthogonal wavelength shifter (WLS) strips, both individually read out by silicon photo-multipliers. Its design decouples sensitivity and spatial resolution, by reducing the parallax error due to the layered arrangement of the crystals. Additionally the granularity of AX-PET enhances the capability to track photons within the detector yielding a large fraction of inter-crystal scatter events. These events, if properly processed, can be included in the reconstruction stage further increasing the sensitivity. Its unique features require dedicated Monte-Carlo simulations, enabling the development of the device, interpreting data and allowing the development of reconstruction codes. At the same time the non-conventional design of AX-PET poses several challenges to the simulation and modeling tasks, mostly related to the light transport and distribution within the crystals and WLS strips, as well as the electronics readout. In this work we present a hybrid simulation tool based on an analytical model and a Monte-Carlo based description of the AX-PET demonstrator. It was extensively validated against experimental data, providing excellent agreement.
Address [Solevi, P.; Oliver, J. F.; Gillam, J. E.; Rafecas, M.] Univ Valencia, CSIC, IFIC, E-46071 Valencia, Spain, Email: paola.solevi@ific.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:000322775300012 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1544
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Author DEPFET collaboration (Alonso, O. et al); Boronat, M.; Esperante-Pereira, D.; Fuster, J.; Garcia, I.G.; Lacasta, C.; Oyanguren, A.; Ruiz, P.; Timon, G.; Vos, M.
Title DEPFET Active Pixel Detectors for a Future Linear e(+)e(-) Collider Type Journal Article
Year 2013 Publication IEEE Transactions on Nuclear Science Abbreviated Journal IEEE Trans. Nucl. Sci.
Volume (up) 60 Issue 2 Pages 1457-1465
Keywords Active pixel sensor; DEPFET; linear collider; vertex detector
Abstract The DEPFET collaboration develops highly granular, ultra-transparent active pixel detectors for high-performance vertex reconstruction at future collider experiments. The characterization of detector prototypes has proven that the key principle, the integration of a first amplification stage in a detector-grade sensor material, can provide a comfortable signal to noise ratio of over 40 for a sensor thickness of 50-75 μm. ASICs have been designed and produced to operate a DEPFET pixel detector with the required read-out speed. A complete detector concept is being developed, including solutions for mechanical support, cooling, and services. In this paper, the status of the DEPFET R & D project is reviewed in the light of the requirements of the vertex detector at a future linear e(+)e(-) collider.
Address [Alonso, O.; Casanova, R.; Dieguez, A.] Univ Barcelona, E-08028 Barcelona, Spain, Email: marcel.vos@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:000320856800029 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1489
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