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Author Aguiar, P.; Rafecas, M.; Ortuño, J.E.; Kontaxakis, G.; Santos, A.; Pavia, J.; Rosetti, M. doi  openurl
  Title Geometrical and Monte Carlo projectors in 3D PET reconstruction Type Journal Article
  Year 2010 Publication Medical Physics Abbreviated Journal Med. Phys.  
  Volume 37 Issue 11 Pages 5691-5702  
  Keywords 3D PET; iterative reconstruction; list-mode reconstruction; ray-tracing techniques; Monte Carlo simulation; system response matrix  
  Abstract Purpose: In the present work, the authors compare geometrical and Monte Carlo projectors in detail. The geometrical projectors considered were the conventional geometrical Siddon ray-tracer (S-RT) and the orthogonal distance-based ray-tracer (OD-RT), based on computing the orthogonal distance from the center of image voxel to the line-of-response. A comparison of these geometrical projectors was performed using different point spread function (PSF) models. The Monte Carlo-based method under consideration involves an extensive model of the system response matrix based on Monte Carlo simulations and is computed off-line and stored on disk. Methods: Comparisons were performed using simulated and experimental data of the commercial small animal PET scanner rPET. Results: The results demonstrate that the orthogonal distance-based ray-tracer and Siddon ray-tracer using PSF image-space convolutions yield better images in terms of contrast and spatial resolution than those obtained after using the conventional method and the multiray-based S-RT. Furthermore, the Monte Carlo-based method yields slight improvements in terms of contrast and spatial resolution with respect to these geometrical projectors. Conclusions: The orthogonal distance-based ray-tracer and Siddon ray-tracer using PSF image-space convolutions represent satisfactory alternatives to factorizing the system matrix or to the conventional on-the-fly ray-tracing methods for list-mode reconstruction, where an extensive modeling based on Monte Carlo simulations is unfeasible.  
  Address [Aguiar, Pablo] Univ Santiago de Compostela, Dept Fis Particulas, Complexo Hosp Univ Santiago de Compostela, Fdn IDICHUS IDIS, Santiago De Compostela, Spain, Email: pablo.aguiar.fernandez@sergas.es  
  Corporate Author Thesis  
  Publisher Amer Assoc Physicists Medicine Amer Inst Physics Place of Publication Editor (up)  
  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 ISI:000283747600015 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ elepoucu @ Serial 338  
Permanent link to this record
 

 
Author Wagner, C.; Verde, L.; Boubekeur, L. url  doi
openurl 
  Title N-body simulations with generic non-Gaussian initial conditions I: power spectrum and halo mass function Type Journal Article
  Year 2010 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.  
  Volume 10 Issue 10 Pages 022 - 24pp  
  Keywords power spectrum; cosmological simulations; initial conditions and eternal universe; galaxy clusters  
  Abstract We address the issue of setting up generic non-Gaussian initial conditions for N-body simulations. We consider inflationary-motivated primordial non-Gaussianity where the perturbations in the Bardeen potential are given by a dominant Gaussian part plus a non-Gaussian part specified by its bispectrum. The approach we explore here is suitable for any bispectrum, i.e. it does not have to be of the so-called separable or factorizable form. The procedure of generating a non-Gaussian field with a given bispectrum (and a given power spectrum for the Gaussian component) is not univocal, and care must be taken so that higher-order corrections do not leave a too large signature on the power spectrum. This is so far a limiting factor of our approach. We then run N-body simulations for the most popular inflationary-motivated non-Gaussian shapes. The halo mass function and the non-linear power spectrum agree with theoretical analytical approximations proposed in the literature, even if they were so far developed and tested only for a particular shape (the local one). We plan to make the simulations outputs available to the community via the non-Gaussian simulations comparison project web site http://icc.ub.edu/similar to liciaverde/NGSCP.html.  
  Address [Wagner, Christian; Verde, Licia] Univ Barcelona, ICCUB IEEC, E-08028 Barcelona, Spain, Email: cwagner@icc.ub.edu  
  Corporate Author Thesis  
  Publisher Iop Publishing Ltd Place of Publication Editor (up)  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1475-7516 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000283577600013 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ elepoucu @ Serial 339  
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Author Blume, M.; Martinez-Moller, A.; Keil, A.; Navab, N.; Rafecas, M. doi  openurl
  Title Joint Reconstruction of Image and Motion in Gated Positron Emission Tomography Type Journal Article
  Year 2010 Publication IEEE Transactions on Medical Imaging Abbreviated Journal IEEE Trans. Med. Imaging  
  Volume 29 Issue 11 Pages 1892-1906  
  Keywords Gating; motion compensation; positron emission tomography (PET); reconstruction  
  Abstract We present a novel intrinsic method for joint reconstruction of both image and motion in positron emission tomography (PET). Intrinsic motion compensation methods exclusively work on the measured data, without any external motion measurements. Most of these methods separate image from motion estimation: They use deformable image registration/optical flow techniques in order to estimate the motion from individually reconstructed gates. Then, the image is estimated based on this motion information. With these methods, a main problem lies in the motion estimation step, which is based on the noisy gated frames. The more noise is present, the more inaccurate the image registration becomes. As we show both visually and quantitatively, joint reconstruction using a simple deformation field motion model can compete with state-of-the-art image registration methods which use robust multilevel B-spline motion models.  
  Address [Blume, Moritz; Rafecas, Magdalena] Univ Valencia, CSIC, IFIC, E-46071 Valencia, Spain, Email: moritz.blume@cs.tum.edu  
  Corporate Author Thesis  
  Publisher Ieee-Inst Electrical Electronics Engineers Inc Place of Publication Editor (up)  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0278-0062 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000283941800007 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ elepoucu @ Serial 340  
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Author NEMO-3 Collaboration (Argyriades, J. et al); Martin-Albo, J.; Novella, P. url  doi
openurl 
  Title Measurement of the two neutrino double beta decay half-life of Zr-96 with the NEMO-3 detector Type Journal Article
  Year 2010 Publication Nuclear Physics A Abbreviated Journal Nucl. Phys. A  
  Volume 847 Issue 3-4 Pages 168-179  
  Keywords RADIOACTIVITY Zr-96(2 beta); measured E-beta,E- E-gamma, beta beta-, beta gamma-coin; deduced T-1/2 for 2 nu beta beta-decay, NEMO-3 detector  
  Abstract Using 9.4 g of Zr-96 isotope and 1221 days of data from the NEMO-3 detector corresponding (0 0.031 kg y, the obtained 2 nu beta beta decay half-life measurement is T-1/2(2 nu) = [2.35 +/- 0.14(stat) +/- 0.16(syst)] x 10(19) yr. Different characteristics of the final state electrons have been studied, such as the energy sum, individual electron energy, and angular distribution. The 2v nuclear matrix element is extracted using the measured 2 nu beta beta half-life and is M-2 nu = 0.049 +/- 0.002. Constraints on 0 nu beta beta decay have also been set.  
  Address [Basharina-Freshville, A.; Chapon, A.; Daraktchieva, Z.; Flack, R.; Kauer, M.; King, S.; Saakyan, R.; Thomas, J.; Vasiliev, V.] UCL, London WC1E 6BT, England, Email: kauer@hep.ucl.ac.uk  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor (up)  
  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 ISI:000283955700003 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ elepoucu @ Serial 337  
Permanent link to this record
 

 
Author Marco-Hernandez, R. doi  openurl
  Title Development of a beam test telescope based on the Alibava readout system Type Journal Article
  Year 2011 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.  
  Volume 6 Issue Pages C01002 - 7pp  
  Keywords Particle tracking detectors; Data acquisition circuits; Front-end electronics for detector readout; Digital electronic circuits  
  Abstract A telescope for a beam test have been developed as a result of a collaboration among the University of Liverpool, Centro Nacional de Microelectronica (CNM) of Barcelona and Instituto de Fisica Corpuscular (IFIC) of Valencia. This system is intended to carry out both analogue charge collection and spatial resolution measurements with different types of microstrip or pixel silicon detectors in a beam test environment. The telescope has four XY measurement as well as trigger planes (XYT board) and it can accommodate up to twelve devices under test (DUT board). The DUT board uses two Beetle ASICs for the readout of chilled silicon detectors. The board could operate in a self-triggering mode. The board features a temperature sensor and it can be mounted on a rotary stage. A peltier element is used for cooling the DUT. Each XYT board measures the track space points using two silicon strip detectors connected to two Beetle ASICs. It can also trigger on the particle tracks in the beam test. The board includes a CPLD which allows for the synchronization of the trigger signal to a common clock frequency, delaying and implementing coincidence with other XYT boards. An Alibava mother board is used to read out and to control each XYT/DUT board from a common trigger signal and a common clock signal. The Alibava board has a TDC on board to have a time stamp of each trigger. The data collected by each Alibava board is sent to a master card by means of a local data/address bus following a custom digital protocol. The master board distributes the trigger, clock and reset signals. It also merges the data streams from up to sixteen Alibava boards. The board has also a test channel for testing in a standard mode a XYT or DUT board. This board is implemented with a Xilinx development board and a custom patch board. The master board is connected with the DAQ software via 100M Ethernet. Track based alignment software has also been developed for the data obtained with the DAQ software.  
  Address [Marco-Hernandez, R.; Alibava Collaboration] CSIC UV, Inst Fis Corpuscular, E-46980 Paterna, Valencia, Spain, Email: rmarco@ific.uv.es  
  Corporate Author Thesis  
  Publisher Iop Publishing Ltd Place of Publication Editor (up)  
  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 ISI:000291345600007 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ elepoucu @ Serial 644  
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Author ANTARES Collaboration (Aguilar, J.A. et al); Bigongiari, C.; Dornic, D.; Emanuele, U.; Gomez-Gonzalez, J.P.; Hernandez-Rey, J.J.; Mangano, S.; Salesa, F.; Toscano, S.; Yepes, H.; Zornoza, J.D.; Zuñiga, J. url  doi
openurl 
  Title Zenith distribution and flux of atmospheric muons measured with the 5-line ANTARES detector Type Journal Article
  Year 2010 Publication Astroparticle Physics Abbreviated Journal Astropart Phys.  
  Volume 34 Issue 3 Pages 179-184  
  Keywords Atmospheric muons; Neutrino telescope; Depth-intensity relation  
  Abstract The ANTARES high-energy neutrino telescope is a three-dimensional array of about 900 photomultipliers distributed over 12 mooring lines installed in the Mediterranean Sea. Between February and November 2007 it acquired data in a 5-line configuration. The zenith angular distribution of the atmospheric muon flux and the associated depth-intensity relation are measured and compared with previous measurements and Monte Carlo expectations. An evaluation of the systematic effects due to uncertainties on environmental and detector parameters is presented.  
  Address [Bazzotti, M.; Biagi, S.; Carminati, G.; Giacomelli, G.; Margiotta, A.; Spurio, M.] Dipartimento Fis Univ, I-40127 Bologna, Italy, Email: Annarita.Margiotta@bo.infn.it  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor (up)  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0927-6505 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000282496000005 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ elepoucu @ Serial 373  
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Author Staub, F.; Porod, W.; Herrmann, B. url  doi
openurl 
  Title The electroweak sector of the NMSSM at the one-loop level Type Journal Article
  Year 2010 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.  
  Volume 10 Issue 10 Pages 040 - 50pp  
  Keywords Supersymmetry Phenomenology  
  Abstract We present the electroweak spectrum for the Next-to-Minimal Supersymmetric Standard Model at the one-loop level, e. g. the masses of Higgs bosons, sleptons, charginos and neutralinos. For the numerical evaluation we present a mSUGRA variant with non-universal Higgs mass parameters squared and we compare our results with existing ones in the literature. Moreover, we briefly discuss the implications of our results for the calculation of the relic density.  
  Address [Staub, Florian; Porod, Werner; Herrmann, Bjoern] Univ Wurzburg, Inst Theoret Phys & Astrophys, D-97074 Wurzburg, Germany, Email: florian.staub@physik.uni-wuerzburg.de  
  Corporate Author Thesis  
  Publisher Springer Place of Publication Editor (up)  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1126-6708 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000284146800040 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ elepoucu @ Serial 310  
Permanent link to this record
 

 
Author Meloni, D.; Morisi, S.; Peinado, E. url  doi
openurl 
  Title Neutrino phenomenology and stable dark matter with A(4) Type Journal Article
  Year 2011 Publication Physics Letters B Abbreviated Journal Phys. Lett. B  
  Volume 697 Issue 4 Pages 339-342  
  Keywords Flavor symmetries; Dark matter; Neutrino masses; Lepton mixing; Discrete symmetries; Neutrino less double beta decay  
  Abstract We present a model based on the A(4) non-Abelian discrete symmetry leading to a predictive five-parameter neutrino mass matrix and providing a stable dark matter candidate. We found an interesting correlation among the atmospheric and the reactor angles which predicts theta(23) similar to pi/4for very small reactor angle and deviation from maximal atmospheric mixing for large theta(13). Only normal neutrino mass spectrum is possible and the effective mass entering the neutrinoless double beta decay rate is constrained to be vertical bar m(ee)vertical bar > 4 x 10(-4) eV.  
  Address [Morisi, S.; Peinado, E.] Univ Valencia, CSIC, Inst Fis Corpuscular, AHEP Grp, E-46071 Valencia, Spain, Email: davide.meloni@physik.uni-wuerzburg.de  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor (up)  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0370-2693 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000288300400012 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 544  
Permanent link to this record
 

 
Author Bierenbaum, I.; Catani, S.; Draggiotis, P.; Rodrigo, G. url  doi
openurl 
  Title A tree-loop duality relation at two loops and beyond Type Journal Article
  Year 2010 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.  
  Volume 10 Issue 10 Pages 073 - 22pp  
  Keywords NLO Computations; QCD  
  Abstract The duality relation between one-loop integrals and phase-space integrals, developed in a previous work, is extended to higher-order loops. The duality relation is realized by a modification of the customary +i0 prescription of the Feynman propagators, which compensates for the absence of the multiple-cut contributions that appear in the Feynman tree theorem. We rederive the duality theorem at one-loop order in a form that is more suitable for its iterative extension to higher-loop orders. We explicitly show its application to two-and three-loop scalar master integrals, and we discuss the structure of the occurring cuts and the ensuing results in detail.  
  Address [Bierenbaum, Isabella; Draggiotis, Petros; Rodrigo, German] Univ Valencia, Consejo Super Invest Cient, Inst Fis Corpuscular, E-46071 Valencia, Spain, Email: isabella.bierenbaum@ific.uv.es  
  Corporate Author Thesis  
  Publisher Springer Place of Publication Editor (up)  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1126-6708 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000284147000016 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ elepoucu @ Serial 326  
Permanent link to this record
 

 
Author Garonna, A.; Amaldi, U.; Bonomi, R.; Campo, D.; Degiovanni, A.; Garlasche, M.; Mondino, I.; Rizzoglio, V.; Verdu-Andres, S. url  doi
openurl 
  Title Cyclinac medical accelerators using pulsed C6+/H-2(+) ion sources Type Journal Article
  Year 2010 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.  
  Volume 5 Issue Pages C09004 - 19pp  
  Keywords Instrumentation for particle-beam therapy; Instrumentation for hadron therapy; Ion sources (positive ions, negative ions, electron cyclotron resonance (ECR), electron beam (EBIS)); Acceleration cavities and magnets superconducting (high-temperature superconductor; radiation hardened magnets; normal-conducting; permanent magnet devices; wigglers and undulators)  
  Abstract Charged particle therapy, or so-called hadrontherapy, is developing very rapidly. There is large pressure on the scientific community to deliver dedicated accelerators, providing the best possible treatment modalities at the lowest cost. In this context, the Italian research Foundation TERA is developing fast-cycling accelerators, dubbed 'cyclinacs'. These are a combination of a cyclotron (accelerating ions to a fixed initial energy) followed by a high gradient linac boosting the ions energy up to the maximum needed for medical therapy. The linac is powered by many independently controlled klystrons to vary the beam energy from one pulse to the next. This accelerator is best suited to treat moving organs with a 4D multipainting spot scanning technique. A dual proton/carbon ion cyclinac is here presented. It consists of an Electron Beam Ion Source, a superconducting isochronous cyclotron and a high-gradient linac. All these machines are pulsed at high repetition rate (100-400 Hz). The source should deliver both C6+ and H-2(+) ions in short pulses (1.5 μs flat-top) and with sufficient intensity (at least 10(8) fully stripped carbon ions per pulse at 300 Hz). The cyclotron accelerates the ions to 120 MeV/u. It features a compact design (with superconducting coils) and a low power consumption. The linac has a novel C-band high-gradient structure and accelerates the ions to variable energies up to 400 MeV/u. High RF frequencies lead to power consumptions which are much lower than the ones of synchrotrons for the same ion extraction energy. This work is part of a collaboration with the CLIC group, which is working at CERN on high-gradient electron-positron colliders.  
  Address [Garonna, A.; Amaldi, U.; Bonomi, R.; Campo, D.; Degiovanni, A.; Garlasche, M.; Mondino, I.; Rizzoglio, V.; Andres, S. Verdu] TERA Fdn, I-28100 Novara, Italy, Email: Adriano.Garonna@cern.ch  
  Corporate Author Thesis  
  Publisher Iop Publishing Ltd Place of Publication Editor (up)  
  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 ISI:000283796100011 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ elepoucu @ Serial 327  
Permanent link to this record
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