Records |
Author |
Gillam, J.E.; Solevi, P.; Oliver, J.F.; Casella, C.; Heller, M.; Joram, C.; Rafecas, M. |
Title |
Sensitivity recovery for the AX-PET prototype using inter-crystal scattering events |
Type |
Journal Article |
Year |
2014 |
Publication |
Physics in Medicine and Biology |
Abbreviated Journal |
Phys. Med. Biol. |
Volume |
59 |
Issue |
15 |
Pages |
4065-4083 |
Keywords |
positron emission tomography (PET); inter-crystal scattering; sensitivity |
Abstract |
The development of novel detection devices and systems such as the AX-positron emission tomography (PET) demonstrator often introduce or increase the measurement of atypical coincidence events such as inter-crystal scattering (ICS). In more standard systems, ICS events often go undetected and the small measured fraction may be ignored. As the measured quantity of such events in the data increases, so too does the importance of considering them during image reconstruction. Generally, treatment of ICS events will attempt to determine which of the possible candidate lines of response (LoRs) correctly determine the annihilation photon trajectory. However, methods of assessment often have low success rates or are computationally demanding. In this investigation alternative approaches are considered. Experimental data was taken using the AX-PET prototype and a NEMA phantom. Three methods of ICS treatment were assessed-each of which considered all possible candidate LoRs during image reconstruction. Maximum likelihood expectation maximization was used in conjunction with both standard (line-like) and novel (V-like in this investigation) detection responses modeled within the system matrix. The investigation assumed that no information other than interaction locations was available to distinguish between candidates, yet the methods assessed all provided means by which such information could be included. In all cases it was shown that the signal to noise ratio is increased using ICS events. However, only one method, which used full modeling of the ICS response in the system matrix-the V-like model-provided enhancement in all figures of merit assessed in this investigation. Finally, the optimal method of ICS incorporation was demonstrated using data from two small animals measured using the AX-PET demonstrator. |
Address |
[Gillam, John E.; Solevi, Paola; Oliver, Josep F.; Rafecas, Magdalena] Univ Valencia, CSIC, IFIC, Valencia, Spain, Email: john.gillam@sydney.edu.au |
Corporate Author |
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Thesis |
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Publisher |
Iop Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0031-9155 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000340056800006 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
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Call Number |
IFIC @ pastor @ |
Serial |
1879 |
Permanent link to this record |
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Author |
Pierre Auger Collaboration (Aab, A. et al); Pastor, S. |
Title |
A targeted search for point sources of EeV neutrons |
Type |
Journal Article |
Year |
2014 |
Publication |
Astrophysical Journal Letters |
Abbreviated Journal |
Astrophys. J. Lett. |
Volume |
789 |
Issue |
2 |
Pages |
L34 - 7pp |
Keywords |
cosmic rays; Galaxy: disk; methods: data analysis |
Abstract |
A flux of neutrons from an astrophysical source in the Galaxy can be detected in the Pierre Auger Observatory as an excess of cosmic-ray air showers arriving from the direction of the source. To avoid the statistical penalty for making many trials, classes of objects are tested in combinations as nine “target sets,” in addition to the search for a neutron flux from the Galactic center or from the Galactic plane. Within a target set, each candidate source is weighted in proportion to its electromagnetic flux, its exposure to the Auger Observatory, and its flux attenuation factor due to neutron decay. These searches do not find evidence for a neutron flux from any class of candidate sources. Tabulated results give the combined p-value for each class, with and without the weights, and also the flux upper limit for the most significant candidate source within each class. These limits on fluxes of neutrons significantly constrain models of EeV proton emission from non-transient discrete sources in the Galaxy. |
Address |
[Aab, A.; Buchholz, P.; Erfani, M.; Frohlich, U.; Heimann, P.; Homola, P.; Niechciol, M.; Ochilo, L.; Risse, M.; Yushkov, A.; Ziolkowski, M.] Univ Siegen, D-57068 Siegen, Germany |
Corporate Author |
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Thesis |
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Publisher |
Iop Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2041-8205 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000339876800009 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1885 |
Permanent link to this record |
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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.; Miñano, M.; Mitsou, V.A.; Moles-Valls, R.; Oliver Garcia, E.; Pedraza Lopez, S.; Perez Garcia-Estañ, M.T.; Qin, G.; 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.; Villaplana Perez, M.; Vos, M. |
Title |
Monitoring and data quality assessment of the ATLAS liquid argon calorimeter |
Type |
Journal Article |
Year |
2014 |
Publication |
Journal of Instrumentation |
Abbreviated Journal |
J. Instrum. |
Volume |
9 |
Issue |
|
Pages |
P07024 - 55pp |
Keywords |
Particle identification methods; Calorimeters; Large detector systems for particle and astroparticle physics |
Abstract |
The liquid argon calorimeter is a key component of the ATLAS detector installed at the CERN Large Hadron Collider. The primary purpose of this calorimeter is the measurement of electron and photon kinematic properties. It also provides a crucial input for measuring jets and missing transverse momentum. An advanced data monitoring procedure was designed to quickly identify issues that would affect detector performance and ensure that only the best quality data are used for physics analysis. This article presents the validation procedure developed during the 2011 and 2012 LHC data-taking periods, in which more than 98% of the proton-proton luminosity recorded by ATLAS at a centre-of-mass energy of 7-8 TeV had calorimeter data quality suitable for physics analysis. |
Address |
[Jackson, P.; Soni, N.; White, M. J.] Univ Adelaide, Dept Phys, Adelaide, SA, Australia |
Corporate Author |
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Thesis |
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Publisher |
Iop Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1748-0221 |
ISBN |
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Medium |
|
Area |
|
Expedition |
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Conference |
|
Notes |
WOS:000340050700045 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1915 |
Permanent link to this record |
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Author |
Alvarez-Ruso, L.; Hayato, Y.; Nieves, J. |
Title |
Progress and open questions in the physics of neutrino cross sections at intermediate energies |
Type |
Journal Article |
Year |
2014 |
Publication |
New Journal of Physics |
Abbreviated Journal |
New J. Phys. |
Volume |
16 |
Issue |
|
Pages |
075015 - 62pp |
Keywords |
neutrino cross sections; oscillation experiments; electroweak hadronic form factors; nuclear effects |
Abstract |
New and more precise measurements of neutrino cross sections have renewed interest in a better understanding of electroweak interactions on nucleons and nuclei. This effort is crucial to achieving the precision goals of the neutrino oscillation program, making new discoveries, like the CP violation in the leptonic sector, possible. We review the recent progress in the physics of neutrino cross sections, putting emphasis on the open questions that arise in the comparison with new experimental data. Following an overview of recent neutrino experiments and future plans, we present some details about the theoretical development in the description of (anti) neutrino-induced quasielastic (QE) scattering and the role of multi-nucleon QE-like mechanisms. We cover not only pion production in nucleons and nuclei but also other inelastic channels including strangeness production and photon emission. Coherent reaction channels on nuclear targets are also discussed. Finally, we briefly describe some of the Monte Carlo event generators, which are at the core of all neutrino oscillation and cross-section measurements. |
Address |
[Alvarez-Ruso, L.; Nieves, J.] Univ Valencia, Ctr Mixto CSIC, Inst Fis Corpuscular IFIC, E-46071 Valencia, Spain, Email: luis.alvarez@ific.uv.es |
Corporate Author |
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Thesis |
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Publisher |
Iop Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
1367-2630 |
ISBN |
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Medium |
|
Area |
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Expedition |
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Conference |
|
Notes |
WOS:000341829000001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1927 |
Permanent link to this record |
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|
Author |
Pierre Auger Collaboration (Aab, A. et al); Pastor, S. |
Title |
Reconstruction of inclined air showers detected with the pierre Auger Observatory |
Type |
Journal Article |
Year |
2014 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
Volume |
08 |
Issue |
8 |
Pages |
019 - 32pp |
Keywords |
ultra high energy cosmic rays; cosmic ray experiments |
Abstract |
We describe the method devised to reconstruct inclined cosmic-ray air showers with zenith angles greater than 60 degrees detected with the surface array of the Pierre Auger Observatory. The measured signals at the ground level are fitted to muon density distributions predicted with atmospheric cascade models to obtain the relative shower size as an overall normalization parameter. The method is evaluated using simulated showers to test its performance. The energy of the cosmic rays is calibrated using a sub-sample of events reconstructed with both the fluorescence and surface array techniques. The reconstruction method described here provides the basis of complementary analyses including an independent measurement of the energy spectrum of ultra-high energy cosmic rays using very inclined events collected by the Pierre Auger Observatory. |
Address |
[Anchordoqui, L.] CUNY, CUNY Herbert H Lehman Coll, Dept Phys & Astron, New York, NY 10021 USA |
Corporate Author |
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Thesis |
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Publisher |
Iop Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1475-7516 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
|
Notes |
WOS:000341848800019 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1942 |
Permanent link to this record |
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Author |
Easther, R.; Price, L.C.; Rasero, J. |
Title |
Inflating an inhomogeneous universe |
Type |
Journal Article |
Year |
2014 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
Volume |
08 |
Issue |
8 |
Pages |
041 - 16pp |
Keywords |
inflation; initial conditions and eternal universe; physics of the early universe |
Abstract |
While cosmological inflation can erase primordial inhomogeneities, it is possible that inflation may not begin in a significantly inhomogeneous universe. This issue is particularly pressing in multifield scenarios, where even the homogeneous dynamics may depend sensitively on the initial configuration. This paper presents an initial survey of the onset of inflation in multifield models, via qualitative lattice-based simulations that do not include local gravitational backreaction. Using hybrid inflation as a test model, our results suggest that small subhorizon inhomogeneities do play a key role in determining whether inflation begins in multifield scenarios. Interestingly, some configurations which do not inflate in the homogeneous limit “succeed” after inhomogeneity is included, while other initial configurations which inflate in the homogeneous limit “fail” when inhomogeneity is added. |
Address |
[Easther, Richard; Price, Layne C.] Univ Auckland, Dept Phys, Auckland, New Zealand, Email: r.easther@auckland.ac.nz; |
Corporate Author |
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Thesis |
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Publisher |
Iop Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1475-7516 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
|
Notes |
WOS:000341848800041 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1943 |
Permanent link to this record |
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Author |
Pallis, C. |
Title |
Induced-gravity in inflation no-scale supergravity and beyond |
Type |
Journal Article |
Year |
2014 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
Volume |
08 |
Issue |
8 |
Pages |
057 - 20pp |
Keywords |
inflation; supersymmetry and cosmology |
Abstract |
Supersymmetric versions of induced-gravity inflation are formulated within Supergravity (SUGRA) employing two gauge singlet chiral super fields. The proposed super-potential is uniquely determined by applying a continuous R and a discrete Z(n) symmetry. We select two types of logarithmic Kahler potentials, one associated with a no-scale-type SU(2, 1)/SU(2) x U(1)(R) x Z(n) Kahler manifold and one more generic. In both cases, imposing a lower bound on the parameter c R involved in the coupling between the inflaton and the Ricci scalar curvature – e.g. c(R) greater than or similar to 76, 105, 310 for n – 2, 3 and 6 respectively -, inflation can be attained even for subplanckian values of the inflaton while the corresponding effective theory respects the perturbative unitarity. In the case of no-scale SUGRA we show that, for every n, the inflationary observables remain unchanged and in agreement with the current data while the inflaton mass is predicted to be 3 . 10(13) GeV. Beyond no-scale SUGRA the inflationary observables depend mildly on n and crucially on the coefficient involved in the fourth order term of the Kahler potential which mixes the inflaton with the accompanying non-inflaton field. |
Address |
[Pallis, C.] Univ Valencia, CSIC, Dept Fis Teor, E-46100 Burjassot, Spain, Email: kpallis@gen.auth.gr |
Corporate Author |
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Thesis |
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Publisher |
Iop Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1475-7516 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000341848800057 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ pastor @ |
Serial |
1944 |
Permanent link to this record |
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Author |
ATLAS Collaboration (Aad, G. et al); Bernabeu Verdu, J.; Cabrera Urban, S.; Castillo Gimenez, V.; Costa, M.J.; Fassi, F.; Ferrer, A.; Fiorini, L.; Fuster, J.; Garcia, C.; Garcia-Argos, 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.; Miñano, M.; 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.; Villaplana Perez, M.; Vos, M. |
Title |
Operation and performance of the ATLAS semiconductor tracker |
Type |
Journal Article |
Year |
2014 |
Publication |
Journal of Instrumentation |
Abbreviated Journal |
J. Instrum. |
Volume |
9 |
Issue |
|
Pages |
P08009 - 73pp |
Keywords |
Solid state detectors; Charge transport and multiplication in solid media; Particle tracking detectors (Solid-state detectors); Detector modelling and simulations I (interaction of radiation with matter, interaction of photons with matter, interaction of hadrons with matter, etc) |
Abstract |
The semiconductor tracker is a silicon microstrip detector forming part of the inner tracking system of the ATLAS experiment at the LHC. The operation and performance of the semiconductor tracker during the first years of LHC running are described. More than 99% of the detector modules were operational during this period, with an average intrinsic hit efficiency of (99.74 +/- 0.04)%. The evolution of the noise occupancy is discussed, and measurements of the Lorentz angle, delta-ray production and energy loss presented. The alignment of the detector is found to be stable at the few-micron level over long periods of time. Radiation damage measurements, which include the evolution of detector leakage currents, are found to be consistent with predictions and are used in the verification of radiation background simulations. |
Address |
[Jackson, P.; Soni, N.; White, M. J.] Univ Adelaide, Dept Phys, Adelaide, SA, Australia |
Corporate Author |
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Thesis |
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Publisher |
Iop Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1748-0221 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
|
Notes |
WOS:000341927600037 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1945 |
Permanent link to this record |
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Author |
Rebel, B.; Hall, C.; Bernard, E.; Faham, C.H.; Ito, T.M.; Lundberg, B.; Messina, M.; Monrabal, F.; Pereverzev, S.P.; Resnati, F.; Rowson, P.C.; Soderberg, M.; Strauss, T.; Tomas, A.; Va'vra, J.; Wang, H. |
Title |
High voltage in noble liquids for high energy physics |
Type |
Journal Article |
Year |
2014 |
Publication |
Journal of Instrumentation |
Abbreviated Journal |
J. Instrum. |
Volume |
9 |
Issue |
|
Pages |
T08004 - 57pp |
Keywords |
Noble liquid detectors (scintillation, ionization, double-phase); Neutrino detectors; Neutron detectors (cold, thermal, fast neutrons); Dark Matter detectors (WIMPs, axions, etc.) |
Abstract |
A workshop was held at Fermilab November 8-9, 2013 to discuss the challenges of using high voltage in noble liquids. The participants spanned the fields of neutrino, dark matter, and electric dipole moment physics. All presentations at the workshop were made in plenary sessions. This document summarizes the experiences and lessons learned from experiments in these fields at developing high voltage systems in noble liquids. |
Address |
[Rebel, B.; Soderberg, M.] Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA, Email: rebel@fnal.gov |
Corporate Author |
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Thesis |
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Publisher |
Iop Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1748-0221 |
ISBN |
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Medium |
|
Area |
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Expedition |
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Conference |
|
Notes |
WOS:000341927600043 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1947 |
Permanent link to this record |
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Author |
Gonzalez, P. |
Title |
Generalized screened potential model |
Type |
Journal Article |
Year |
2014 |
Publication |
Journal of Physics G |
Abbreviated Journal |
J. Phys. G |
Volume |
41 |
Issue |
9 |
Pages |
095001 - 12pp |
Keywords |
quark; meson; potential |
Abstract |
A new non relativistic quark model to calculate the spectrum of heavy quark mesons is developed. The model is based on an interquark potential interaction that implicitly incorporates screening effects from meson-meson configurations. An analysis of the bottomonium spectrum shows the appearance of extra states as compared to conventional non screened potential models. |
Address |
Univ Valencia, CSIC, IFIC, Dept Fis Teor, E-46100 Burjassot, Valencia, Spain, Email: pedro.gonzalez@uv.es |
Corporate Author |
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Thesis |
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Publisher |
Iop Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0954-3899 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000342356400014 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ pastor @ |
Serial |
1955 |
Permanent link to this record |