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Author Brzezinski, K.; Oliver, J.F.; Gillam, J.; Rafecas, M.
Title Study of a high-resolution PET system using a Silicon detector probe Type Journal Article
Year 2014 Publication Physics in Medicine and Biology Abbreviated Journal Phys. Med. Biol.
Volume 59 Issue 20 Pages 6117-6140
Keywords PET; high-resolution imaging; Si detectors; PET insert
Abstract A high-resolution silicon detector probe, in coincidence with a conventional PET scanner, is expected to provide images of higher quality than those achievable using the scanner alone. Spatial resolution should improve due to the finer pixelization of the probe detector, while increased sensitivity in the probe vicinity is expected to decrease noise. A PET-probe prototype is being developed utilizing this principle. The system includes a probe consisting of ten layers of silicon detectors, each a 80 x 52 array of 1 x 1 x 1 mm(3) pixels, to be operated in coincidence with a modern clinical PET scanner. Detailed simulation studies of this system have been performed to assess the effect of the additional probe information on the quality of the reconstructed images. A grid of point sources was simulated to study the contribution of the probe to the system resolution at different locations over the field of view (FOV). A resolution phantom was used to demonstrate the effect on image resolution for two probe positions. A homogeneous source distribution with hot and cold regions was used to demonstrate that the localized improvement in resolution does not come at the expense of the overall quality of the image. Since the improvement is constrained to an area close to the probe, breast imaging is proposed as a potential application for the novel geometry. In this sense, a simplified breast phantom, adjacent to heart and torso compartments, was simulated and the effect of the probe on lesion detectability, through measurements of the local contrast recovery coefficient-to-noise ratio (CNR), was observed. The list-mode ML-EM algorithm was used for image reconstruction in all cases. As expected, the point spread function of the PET-probe system was found to be non-isotropic and vary with position, offering improvement in specific regions. Increase in resolution, of factors of up to 2, was observed in the region close to the probe. Images of the resolution phantom showed visible improvement in resolution when including the probe in the simulations. The image quality study demonstrated that contrast and spill-over ratio in other areas of the FOV were not sacrificed for this enhancement. The CNR study performed on the breast phantom indicates increased lesion detectability provided by the probe.
Address [Brzezinski, K.; Oliver, J. F.; Gillam, J.; Rafecas, M.] Univ Valencia, CSIC, Inst Fis Corpuscular, E-46980 Valencia, Spain, Email: brzezinski@ific.uv.es
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language (up) 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:000343092300011 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1963
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Author DELPHI Collaboration (Abdallah, J. et al); Costa, M.J.; Ferrer, A.; Fuster, J.; Garcia, C.; Oyanguren, A.; Perepelitsa, V.; Salt, J.; Tortosa, P.
Title Measurement of the electron structure function F-2(e) at LEP energies Type Journal Article
Year 2014 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 737 Issue Pages 39-47
Keywords
Abstract The hadronic part of the electron structure function F-2(e) has been measured for the first time, using e(+)e(-) data collected by the DELPHI experiment at LEP, at centre-of-mass energies of root s = 91.2-209.5 GeV. The data analysis is simpler than that of the measurement of the photon structure function. The electron structure function F-2(e) data are compared to predictions of phenomenological models based on the photon structure function. It is shown that the contribution of large target photon virtualities is significant. The data presented can serve as a cross-check of the photon structure function F-2(gamma) analyses and help in refining existing parameterizations.
Address [Lamsa, J.] Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language (up) 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 WOS:000342757700008 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1965
Permanent link to this record
 

 
Author Liang, W.H.; Oset, E.
Title B-0 and B-s(0) decays into J/psi f(0)(980) and J/psi f(0)(500) and the nature of the scalar resonances Type Journal Article
Year 2014 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 737 Issue Pages 70-74
Keywords
Abstract We describe the B-0 and B-s(0) decays into J/psi f(0)(500) and J/psi f(0)(980) by taking into account the dominant process for the weak decay of B-0 and B-s(0) into J/psi and a q (q) over bar component. After hadronization of this q (q) over bar component into pairs of pseudoscalar mesons we obtain certain weights for the meson-meson components and allow them to interact among themselves. The final state interaction of the meson-meson components, described in terms of chiral unitary theory, gives rise to the f(0)(980) and f(0)(500) resonances and we can obtain the pi(+)pi(-) invariant mass distributions after the decay of the resonances, which allows us to compare directly to the experiments. We obtain ratios of J/psi f(0)(980) and J/psi f(0)( 500) for each of the B decays in quantitative agreement with experiment, with the f(0)(980) clearly dominant in the B-s(0) decay and the f(0)(500) in the B-0 decay.
Address [Liang, W. H.] Guangxi Normal Univ, Dept Phys, Guilin 541004, Peoples R China
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language (up) 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 WOS:000342757700013 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1966
Permanent link to this record
 

 
Author Celis, A.; Fuentes-Martin, J.; Serodio, H.
Title Effective aligned 2HDM with a DFSZ-like invisible axion Type Journal Article
Year 2014 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 737 Issue Pages 185-190
Keywords
Abstract We discuss the possibility of having a non-minimal scalar sector at the weak scale within the framework of invisible axion models. To frame our discussion we consider an extension of the Dine-Fischler-Srednicki-Zhitnitsky invisible axion model with two additional Higgs doublets blind under the Peccei-Quinn symmetry. Due to mixing effects among the scalar fields, it is possible to obtain a rich scalar sector at the weak scale in certain decoupling limits of the theory. In particular, this framework provides an ultraviolet completion of the so-called aligned two-Higgs-doublet model and solves the strong CP problem. The axion properties and the smallness of active neutrino masses are also discussed.
Address [Serodio, Hugo] Univ Valencia, CSIC, Dept Fis Teor, E-46100 Burjassot, Spain, Email: alejandro.celis@ific.uv.es;
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language (up) 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 WOS:000342757700032 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 1967
Permanent link to this record
 

 
Author ATLAS Collaboration (Aad, G. et al); Cabrera Urban, S.; Castillo Gimenez, V.; Costa, M.J.; Fassi, F.; Ferrer, A.; Fiorini, L.; Fuster, J.; Garcia, C.; Garcia Navarro, J.E.; Gonzalez de la Hoz, S.; Hernandez Jimenez, Y.; Higon-Rodriguez, E.; Irles Quiles, A.; Kaci, M.; King, M.; Lacasta, C.; Lacuesta, V.R.; March, L.; Marti-Garcia, S.; Mitsou, V.A.; Moles-Valls, R.; Oliver Garcia, E.; Pedraza Lopez, S.; Perez Garcia-Estañ, M.T.; Romero Adam, E.; Ros, E.; Salt, J.; Sanchez Martinez, V.; Soldevila, U.; Sanchez, J.; Torro Pastor, E.; Valero, A.; Valladolid Gallego, E.; Valls Ferrer, J.A.; Vos, M.
Title Search for WZ resonances in the fully leptonic channel using pp collisions at root s=8 TeV with the ATLAS detector Type Journal Article
Year 2014 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 737 Issue Pages 223-243
Keywords
Abstract A search for resonant WZ production in the l nu l'l' (l, l' = e, mu) decay channel using 20.3 fb(-1) of root s = 8 TeV pp collision data collected by the ATLAS experiment at LHC is presented. No significant deviation from the Standard Model prediction is observed and upper limits on the production cross sections of WZ resonances from an extended gauge model W' and from a simplified model of heavy vector triplets are derived. A corresponding observed (expected) lower mass limit of 1.52 (1.49) TeV is derived for the W' at the 95% confidence level. (C) 2014 CERN for the benefit of the ATLAS Collaboration.
Address [Jackson, P.; Soni, N.; White, M. J.] Univ Adelaide, Dept Phys, Adelaide, SA, Australia
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language (up) 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 WOS:000342757700039 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1968
Permanent link to this record