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Author Granero, D.; Vijande, J.; Ballester, F.; Rivard, M.J.
Title Dosimetry revisited for the HDR Ir-192 brachytherapy source model mHDR-v2 Type Journal Article
Year 2011 Publication Medical Physics Abbreviated Journal Med. Phys.
Volume 38 Issue 1 Pages 487-494
Keywords Ir-192; brachytherapy; dosimetry; TG-43; PSS model; MCNP5; PENELOPE2008; GEANT4
Abstract Purpose: Recently, the manufacturer of the HDR Ir-192 mHDR-v2 brachytherapy source reported small design changes (referred to herein as mHDR-v2r) that are within the manufacturing tolerances but may alter the existing dosimetric data for this source. This study aimed to (1) check whether these changes affect the existing dosimetric data published for this source; (2) obtain new dosimetric data in close proximity to the source, including the contributions from 192Ir electrons and considering the absence of electronic equilibrium; and (3) obtain scatter dose components for collapsed cone treatment planning system implementation. Methods: Three different Monte Carlo (MC) radiation transport codes were used: MCNP5, PENELOPE2008, and GEANT4. The source was centrally positioned in a 40 cm radius water phantom. Absorbed dose and collision kerma were obtained using 0.1 mm (0.5 mm) thick voxels to provide high-resolution dosimetry near (far from) the source. Dose-rate distributions obtained with the three MC codes were compared. Results: Simulations of mHDR-v2 and mHDR-v2r designs performed with three radiation transport codes showed agreement typically within 0.2% for r >= 0.25 cm. Dosimetric contributions from source electrons were significant for r<0.25 cm. The dose-rate constant and radial dose function were similar to those from previous MC studies of the mHDR-v2 design. The 2D anisotropy function also coincided with that of the mHDR-v2 design for r >= 0.25 cm. Detailed results of dose distributions and scatter components are presented for the modified source design. Conclusions: Comparison of these results to prior MC studies showed agreement typically within 0.5% for r >= 0.25 cm. If dosimetric data for r<0.25 cm are not needed, dosimetric results from the prior MC studies will be adequate. c 2011 American Association of Physicists in Medicine.
Address [Granero, Domingo] Hosp Gen Univ, Dept Radiat Phys, ERESA, E-46014 Valencia, Spain, Email: dgranero@eresa.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 (up) Medium
Area Expedition Conference
Notes ISI:000285769800050 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 557
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Author de Azcarraga, J.A.; Izquierdo, J.M.
Title On a class of n-Leibniz deformations of the simple Filippov algebras Type Journal Article
Year 2011 Publication Journal of Mathematical Physics Abbreviated Journal J. Math. Phys.
Volume 52 Issue 2 Pages 023521 - 13pp
Keywords
Abstract We study the problem of infinitesimal deformations of all real, simple, finite-dimensional Filippov (or n-Lie) algebras, considered as a class of n-Leibniz algebras characterized by having an n-bracket skewsymmetric in its n-1 first arguments. We prove that all n > 3 simple finite-dimensional Filippov algebras (FAs) are rigid as n-Leibniz algebras of this class. This rigidity also holds for the Leibniz deformations of the semisimple n = 2 Filippov (i.e., Lie) algebras. The n = 3 simple FAs, however, admit a nontrivial one-parameter infinitesimal 3-Leibniz algebra deformation. We also show that the n >= 3 simple Filippov algebras do not admit nontrivial central extensions as n-Leibniz algebras of the above class.
Address [de Azcarraga, Jose A.] Univ Valencia, Dept Theoret Phys, E-46100 Burjassot, Valencia, Spain, Email: j.a.de.azcarraga@ific.uv.es
Corporate Author Thesis
Publisher 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 0022-2488 ISBN (up) Medium
Area Expedition Conference
Notes ISI:000287811800050 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 558
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Author Mena, O.; Razzaque, S.; Villaescusa-Navarro, F.
Title Signatures of photon and axion-like particle mixing in the gamma-ray burst jet Type Journal Article
Year 2011 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 02 Issue 2 Pages 030 - 16pp
Keywords axions; magnetic fields; gamma ray bursts theory; gamma ray burst experiments
Abstract Photons couple to Axion-Like Particles (ALPs) or more generally to any pseudo Nambu-Goldstone boson in the presence of an external electromagnetic field. Mixing between photons and ALPs in the strong magnetic field of a Gamma-Ray Burst (GRB) jet during the prompt emission phase can leave observable imprints on the gamma-ray polarization and spectrum. Mixing in the intergalactic medium is not expected to modify these signatures for ALP mass > 10(-14) eV and/or for < nG magnetic field. We show that the depletion of photons due to conversion to ALPs changes the linear degree of polarization from the values predicted by the synchrotron model of gamma ray emission. We also show that when the magnetic field orientation in the propagation region is perpendicular to the field orientation in the production region, the observed synchrotron spectrum becomes steeper than the theoretical prediction and as detected in a sizable fraction of GRB sample. Detection of the correlated polarization and spectral signatures from these steep-spectrum GRBs by gamma-ray polarimeters can be a very powerful probe to discover ALPs. Measurement of gamma-ray polarization from GRBs in general, with high statistics, can also be useful to search for ALPs.
Address [Mena, Olga; Villaescusa-Navarro, F.] Univ Valencia, CSIC, IFIC, E-46071 Valencia, Spain, Email: omena@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 1475-7516 ISBN (up) Medium
Area Expedition Conference
Notes ISI:000287859800031 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 559
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Author Heinze, M.; Malinsky, M.
Title Flavor structure of supersymmetric SO(10) GUTs with extended matter sector Type Journal Article
Year 2011 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 83 Issue 3 Pages 035018 - 16pp
Keywords
Abstract We discuss in detail the flavor structure of the supersymmetric SOd(10) grand unified models with the three traditional 16-dimensional matter spinors mixed with a set of extra ten-dimensional vector multiplets which can provide the desired sensitivity of the standard model matter spectrum to the grand unified theory symmetry breakdown at the renormalizable level. We put the qualitative argument that a successful fit of the quark and lepton data requires an active participation of more than a single vector matter multiplet on a firm, quantitative ground. We find that the strict no-go obtained for the fits of the charged-sector observables in case of a single active matter 10 is relaxed if a second vector multiplet is added to the matter sector and excellent, though nontrivial, fits can be devised. Exploiting the unique calculable part of the neutrino mass matrix governed by the SUd(2)(L) triplet in the 54-dimensional Higgs multiplet, a pair of genuine predictions of the current setting is identified: a nonzero value of the leptonic 1-3 mixing close to the current 90% C.L. limit and a small leptonic Dirac CP phase are strongly preferred by all solutions with the global-fit chi(2) values below 50.
Address [Heinze, Martin; Malinsky, Michal] AlbaNova Univ Ctr, Royal Inst Technol KTH, Dept Theoret Phys, Sch Engn Sci, SE-10691 Stockholm, Sweden, Email: mheinze@kth.se
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN (up) Medium
Area Expedition Conference
Notes ISI:000287655300010 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 566
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Author Bertone, G.; Kong, K.C.; Ruiz de Austri, R.; Trotta, R.
Title Global fits of the minimal universal extra dimensions scenario Type Journal Article
Year 2011 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 83 Issue 3 Pages 036008 - 15pp
Keywords
Abstract In theories with universal extra dimensions (UED), the gamma(1) particle, first excited state of the hypercharge gauge boson, provides an excellent dark matter (DM) candidate. Here, we use a modified version of the SUPERBAYES code to perform a Bayesian analysis of the minimal UED scenario, in order to assess its detectability at accelerators and with DM experiments. We derive, in particular, the most probable range of mass and scattering cross sections off nucleons, keeping into account cosmological and electroweak precision constraints. The consequences for the detectability of the gamma(1) with direct and indirect experiments are dramatic. The spin-independent cross section probability distribution peaks at similar to 10(-11) pb, i.e. below the sensitivity of ton-scale experiments. The spin-dependent cross section drives the predicted neutrino flux from the center of the Sun below the reach of present and upcoming experiments. The only strategy that remains open appears to be direct detection with ton-scale experiments sensitive to spin-dependent cross sections. On the other hand, the LHC with 1 fb(-1) of data should be able to probe the current best-fit UED parameters.
Address [Bertone, Gianfranco] Univ Zurich, Inst Theoret Phys, CH-8057 Zurich, Switzerland
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN (up) Medium
Area Expedition Conference
Notes ISI:000287655300012 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 567
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Author BABAR Collaboration (del Amo Sanchez, P. et al); Lopez-March, N.; Martinez-Vidal, F.; Milanes, D.A.; Oyanguren, A.
Title Measurement of the B -> D(bar)(*) D(*) K branching fractions Type Journal Article
Year 2011 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 83 Issue 3 Pages 032004 - 16pp
Keywords
Abstract We present a measurement of the branching fractions of the 22 decay channels of the B-0 and B+ mesons to (D) over bar (()*()) D-(*()) K, where the D-(*()) and (D) over bar (()*()) mesons are fully reconstructed. Summing the 10 neutral modes and the 12 charged modes, the branching fractions are found to be B(B-0 -> (D) over bar (()*()) D-(*()) K) = (3.68 +/- 0.10 +/- 0.24)% and B(B+ -> (D) over bar (()*()) D-(*()) K) = (4.05 +/- 0.11 +/- 0.28)%, where the first uncertainties are statistical and the second systematic. The results are based on 429 fb(-1) of data containing 471 X 10(6)B (B) over bar pairs collected at the Y(4S) resonance with the BABAR detector at the SLAC National Accelerator Laboratory.
Address [Sanchez, P. del Amo; Lees, J. P.; Poireau, V.; Prencipe, E.; Tisserand, V.] Univ Savoie, LAPP, CNRS, IN2P3, F-74941 Annecy Le Vieux, France
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN (up) Medium
Area Expedition Conference
Notes ISI:000286982700003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 568
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Author Perez-Ramos, R.; Mathieu, V.; Sanchis-Lozano, M.A.
Title Three-particle correlations in QCD parton showers Type Journal Article
Year 2011 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 84 Issue 3 Pages 034015 - 7pp
Keywords
Abstract Three-particle correlations in quark and gluon jets are computed for the first time in perturbative QCD. We give results in the double logarithmic approximation and the modified leading logarithmic approximation. In both resummation schemes, we use the formalism of the generating functional and solve the evolution equations analytically from the steepest descent evaluation of the one-particle distribution. We thus provide a further test of the local parton hadron duality and make predictions for the LHC.
Address [Perez-Ramos, R] Univ Valencia, Dept Fis Teor, CSIC, E-46100 Burjassot, Spain, Email: redamy.perez@uv.es
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN (up) Medium
Area Expedition Conference
Notes WOS:000293703700007 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ elepoucu @ Serial 720
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Author Bridges, M.; Cranmer, K.; Feroz, F.; Hobson, M.; Ruiz de Austri, R.; Trotta, R.
Title A coverage study of the CMSSM based on ATLAS sensitivity using fast neural networks techniques Type Journal Article
Year 2011 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 03 Issue 3 Pages 012 - 23pp
Keywords Supersymmetry; Phenomenology
Abstract We assess the coverage properties of confidence and credible intervals on the CMSSM parameter space inferred from a Bayesian posterior and the profile likelihood based on an ATLAS sensitivity study. In order to make those calculations feasible, we introduce a new method based on neural networks to approximate the mapping between CMSSM parameters and weak-scale particle masses. Our method reduces the computational effort needed to sample the CMSSM parameter space by a factor of similar to 10(4) with respect to conventional techniques. We find that both the Bayesian posterior and the profile likelihood intervals can significantly over-cover and identify the origin of this effect to physical boundaries in the parameter space. Finally, we point out that the effects intrinsic to the statistical procedure are conflated with simplifications to the likelihood functions from the experiments themselves.
Address [Bridges, Michael; Feroz, Farhan; Hobson, Mike] Univ Cambridge, Cavendish Lab, Astrophys Grp, Cambridge CB3 0HE, England, Email: mb435@mrao.cam.ac.uk
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 1126-6708 ISBN (up) Medium
Area Expedition Conference
Notes ISI:000289295200012 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 610
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Author Cederwall, B. et al; Algora, A.; Gadea, A.
Title Evidence for a spin-aligned neutron-proton paired phase from the level structure of Pd-92 Type Journal Article
Year 2011 Publication Nature Abbreviated Journal Nature
Volume 469 Issue 7328 Pages 68-71
Keywords
Abstract Shell structure and magic numbers in atomic nuclei were generally explained by pioneering work(1) that introduced a strong spin-orbit interaction to the nuclear shell model potential. However, knowledge of nuclear forces and the mechanisms governing the structure of nuclei, in particular far from stability, is still incomplete. In nuclei with equal neutron and proton numbers (N = Z), enhanced correlations arise between neutrons and protons (two distinct types of fermions) that occupy orbitals with the same quantum numbers. Such correlations have been predicted to favour an unusual type of nuclear superfluidity, termed isoscalar neutron-proton pairing(2-6), in addition to normal isovector pairing. Despite many experimental efforts, these predictions have not been confirmed. Here we report the experimental observation of excited states in the N = Z = 46 nucleus Pd-92. Gamma rays emitted following the Ni-58(Ar-36,2n)Pd-92 fusion-evaporation reaction were identified using a combination of state-of-the-art high-resolution c-ray, charged-particle and neutron detector systems. Our results reveal evidence for a spin-aligned, isoscalar neutron-proton coupling scheme, different from the previous prediction(2-6). We suggest that this coupling scheme replaces normal superfluidity (characterized by seniority coupling(7,8)) in the ground and low-lying excited states of the heaviest N = Z nuclei. Such strong, isoscalar neutron-proton correlations would have a considerable impact on the nuclear level structure and possibly influence the dynamics of rapid proton capture in stellar nucleosynthesis.
Address [Cederwall, B.; Moradi, F. Ghazi; Back, T.; Johnson, A.; Blomqvist, J.; Andgren, K.; Lagergren, K.; Liotta, R.; Qi, C.; Hadinia, B.; Khaplanov, A.; Persson, A.; Sandzelius, M.] Royal Inst Technol, Dept Phys, SE-10691 Stockholm, Sweden, Email: cederwall@nuclear.kth.se
Corporate Author Thesis
Publisher Nature Publishing Group Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0028-0836 ISBN (up) Medium
Area Expedition Conference
Notes ISI:000285921600032 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 588
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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.
Title Time calibration of the ANTARES neutrino telescope Type Journal Article
Year 2011 Publication Astroparticle Physics Abbreviated Journal Astropart Phys.
Volume 34 Issue 7 Pages 539-549
Keywords Time calibration; Neutrino telescopes; ANTARES
Abstract The ANTARES deep-sea neutrino telescope comprises a three-dimensional array of photomultipliers to detect the Cherenkov light induced by upgoing relativistic charged particles originating from neutrino interactions in the vicinity of the detector. The large scattering length of light in the deep sea facilitates an angular resolution of a few tenths of a degree for neutrino energies exceeding 10 TeV. In order to achieve this optimal performance, the time calibration procedures should ensure a relative time calibration between the photomultipliers at the level of similar to 1 ns. The methods developed to attain this level of precision are described.
Address [Aguilar, J. A.; 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.; Zuniga, J.] Univ Valencia, CSIC, Inst Fis Corpuscular, IFIC, Valencia 46071, Spain, Email: zornoza@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 0927-6505 ISBN (up) Medium
Area Expedition Conference
Notes ISI:000287955500004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 560
Permanent link to this record