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Author Pierre Auger Collaboration (Abreu, P. et al); Pastor, S.
Title The effect of the geomagnetic field on cosmic ray energy estimates and large scale anisotropy searches on data from the Pierre Auger Observatory Type Journal Article
Year 2011 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 11 Issue 11 Pages 022
Keywords
Abstract We present a comprehensive study of the influence of the geomagnetic field on the energy estimation of extensive air showers with a zenith angle smaller than 60 degrees, detected at the Pierre Auger Observatory. the geomagnetic field induces an azimuthal modulation of the estimated energy of cosmic rays up to the similar to 2% level at large zenith angles. We present a method to account for this modulation of the reconstructed energy. We analyse the effect of the modulation on large scale anisotropy searches in the arrival direction distributions of cosmic rays. At a given energy, the geomagnetic effect is shown to induce a pseudo-dipolar pattern at the percent level in the declination distribution that needs to be accounted for.
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 1475-7516 ISBN Medium
Area Expedition Conference
Notes WOS:000298141300022 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 865
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Author Pierre Auger Collaboration (Abreu, P. et al); Pastor, S.
Title Search for ultrahigh energy neutrinos in highly inclined events at the Pierre Auger Observatory Type Journal Article
Year 2011 Publication Physical Review D Abbreviated Journal
Volume 84 Issue 12 Pages 122005
Keywords
Abstract The Surface Detector of the Pierre Auger Observatory is sensitive to neutrinos of all flavors above 0.1 EeV. These interact through charged and neutral currents in the atmosphere giving rise to extensive air showers. When interacting deeply in the atmosphere at nearly horizontal incidence, neutrinos can be distinguished from regular hadronic cosmic rays by the broad time structure of their shower signals in the water-Cherenkov detectors. In this paper we present for the first time an analysis based on down-going neutrinos. We describe the search procedure, the possible sources of background, the method to compute the exposure and the associated systematic uncertainties. No candidate neutrinos have been found in data collected from 1 January 2004 to 31 May 2010. Assuming an E(-2) differential energy spectrum the limit on the single-flavor neutrino is E(2)dN/dE < 1.74 x 10(-7)GeVcm(-2)s(-1)sr(-1) at 90% C.L. in the energy range 1 x 10(17) eV < E < 1 x 10(20)eV.
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 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000298667100001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 863
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Author Roszkowski, L.; Ruiz de Austri, R.; Trotta, R.; Tsai, Y.L.S.; Varley, T.A.
Title Global fits of the nonuniversal Higgs model Type Journal Article
Year 2011 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 83 Issue 1 Pages 015014 - 19pp
Keywords
Abstract We carry out global fits to the nonuniversal Higgs Model (NUHM), applying all relevant present-day constraints. We present global probability maps for the NUHM parameters and observables (including collider signatures, direct, and indirect detection quantities), both in terms of posterior probabilities and in terms of profile likelihood maps. We identify regions of the parameter space where the neutralino dark matter in the model is either binolike, or else higgsinolike with mass close to 1 TeV and a spin-independent scattering cross section similar to 10(-9)-10(-8) pb. We trace the occurrence of the higgsinolike region to be a consequence of a mild focusing effect in the running of one of the Higgs masses, the existence of which in the NUHM we identify in our analysis. Although the usual binolike neutralino is more prominent, higgsinolike dark matter cannot be excluded, however its significance strongly depends on the prior and statistics used to assess it. We note that, despite experimental constraints often favoring different regions of parameter space to the constrained minimal supersymmetric standard model, most observational consequences appear fairly similar, which will make it challenging to distinguish the two models experimentally.
Address [Roszkowski, Leszek; Tsai, Yue-Lin Sming; Varley, Tom A.] Univ Sheffield, Dept Phys & Astron, Sheffield S3 7RH, S Yorkshire, England, Email: L.Roszkowski@sheffield.ac.uk
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 Medium
Area Expedition Conference
Notes ISI:000286765800007 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 586
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Author Sajjad Athar, M.; Ruiz Simo, I.; Vicente Vacas, M.J.
Title Nuclear medium modification of the F2(x, Q^2) structure function Type Journal Article
Year 2011 Publication Nuclear Physics A Abbreviated Journal Nucl. Phys. A
Volume 857 Issue 1 Pages 29-41
Keywords Structure function; Nuclear medium effects; Deep inelastic scattering; Local density approximation
Abstract We study the nuclear effects in the electromagnetic structure function F-2(x, Q(2)) in the deep inelastic lepton nucleus scattering process by taking into account Fermi motion, binding, pion and rho meson cloud contributions. Calculations have been done in a local density approximation using relativistic nuclear spectral functions which include nucleon correlations. The ratios R-F2(A) (x, Q(2)) = 2F(2)(A)(x, Q(2))/AF(2)(D)(x, Q(2)) are obtained and compared with recent JLab results for light nuclei with special attention to the slope of the x distributions. This magnitude shows a non-trivial A dependence and it is insensitive to possible normalization uncertainties. The results have also been compared with some of the older experiments using intermediate mass nuclei.
Address [Athar, M. Sajjad] Aligarh Muslim Univ, Dept Phys, Aligarh 202002, Uttar Pradesh, India, Email: sajathar@gmail.com
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 0375-9474 ISBN Medium
Area Expedition Conference
Notes ISI:000290607500004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 627
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Author Chang, Q.; Li, X.Q.; Yang, Y.D.
Title The effects of a family nonuniversal Z ' boson on B -> pi pi decays Type Journal Article
Year 2011 Publication International Journal of Modern Physics A Abbreviated Journal Int. J. Mod. Phys. A
Volume 26 Issue 7-8 Pages 1273-1294
Keywords B-physics; rare decays; beyond Standard Model
Abstract Motivated by the measured large branching ratio of (B) over bar (0) --> pi(0)pi(0) (the so-called pi pi puzzle), we investigate the effects of a family nonuniversal Z' model on the tree-dominated B --> pi pi decays. We find that the Z' coupling parameter zeta(LR)(d) similar to 0.05 with a nontrivial new weak phase phi(L)(d) similar to -50 degrees, which is relevant to the Z' contributions to the QCD penguin sector Delta C-5, is needed to reconcile the observed discrepancy. Combined with the recent fitting results from B --> pi K, pi K* and rho K decays, the Z' parameter spaces are severely reduced but still not excluded entirely, implying that both the “pi pi” and “pi K” puzzles could be accommodated simultaneously within such a family nonuniversal Z' model.
Address [Chang, Qin; Li, Xin-Qiang] Henan Normal Univ, Dept Phys, Xinxiang 453007, Henan, Peoples R China, Email: changqin@htu.cn
Corporate Author Thesis
Publisher World Scientific Publ Co Pte Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0217-751x ISBN Medium
Area Expedition Conference
Notes ISI:000289175800004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 595
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Author Coloma, P.; Donini, A.; Migliozzi, P.; Lavina, L.S.; Terranova, F.
Title A minimal Beta Beam with high-Q ions to address CP violation in the leptonic sector Type Journal Article
Year 2011 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 71 Issue 6 Pages 1674 - 11pp
Keywords
Abstract In this paper we consider a Beta Beam setup that tries to leverage at most existing European facilities: i.e. a setup that takes advantage of facilities at CERN to boost high-Q ions ((8)Li and (8)B) aiming at a far detector located at L = 732 km in the Gran Sasso Underground Laboratory. The average neutrino energy for (8)Li and (8)B ions boosted at gamma similar to 100 is in the range E(nu) is an element of [1, 2] GeV, high enough to use a large iron detector of the MINOS type at the far site. We perform, then, a study of the neutrino and antineutrino fluxes needed to measure a CP-violating phase delta in a significant part of the parameter space. In particular, for theta(13) >= 3 degrees, if an antineutrino flux of 3 x 10(19) useful (8)Li decays per year is achievable, we find that delta can be measured in 60% of the parameter space with 3 x 10(18) useful (8)B decays per year.
Address [Coloma, P] Univ Autonoma Madrid, Dep Fis Teor, E-28049 Madrid, Spain, Email: andrea.donini@uam.es
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 1434-6044 ISBN Medium
Area Expedition Conference
Notes WOS:000292556400010 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 707
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Author NEMO-3 Collaboration (Argyriades, J. et al); Diaz, J.; Martin-Albo, J.; Monrabal, F.; Novella, P.; Serra, L.; Yahlali, N.
Title Spectral modeling of scintillator for the NEMO-3 and SuperNEMO detectors Type Journal Article
Year 2011 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A
Volume 625 Issue 1 Pages 20-28
Keywords Scintillation; Photomultiplier; Plastic scintillators; Optical photon transport; GEANT 4; Double beta decay
Abstract We have constructed a GEANT4-based detailed software model of photon transport in plastic sontillator blocks and have used it to study the NEMO-3 and SuperNEMO calorimeters employed in experiments designed to search for neutnnoless double beta decay We compare our simulations to measurements using conversion electrons from a calibration source of (BI)-B-207 and show that the agreement is improved if wavelength-dependent properties of the calorimeter are taken into account In this article we briefly describe our modeling approach and results of our studies.
Address [Lang, K.; Pahlka, R. B.] Univ Texas Austin, Dept Phys, Austin, TX 78712 USA
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 0168-9002 ISBN Medium
Area Expedition Conference
Notes ISI:000285432400004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 587
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Author CDF Collaboration (Aaltonen, T. et al); Cabrera, S.
Title Measurement of the B- lifetime using a simulation free approach for trigger bias correction Type Journal Article
Year 2011 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 83 Issue 3 Pages 032008 - 30pp
Keywords
Abstract The collection of a large number of B-hadron decays to hadronic final states at the CDF II Detector is possible due to the presence of a trigger that selects events based on track impact parameters. However, the nature of the selection requirements of the trigger introduces a large bias in the observed proper-decay-time distribution. A lifetime measurement must correct for this bias, and the conventional approach has been to use a Monte Carlo simulation. The leading sources of systematic uncertainty in the conventional approach are due to differences between the data and the Monte Carlo simulation. In this paper, we present an analytic method for bias correction without using simulation, thereby removing any uncertainty due to the differences between data and simulation. This method is presented in the form of a measurement of the lifetime of the B- using the mode B- -> D-0 pi(-). The B- lifetime is measured as tau(-)(B) = 1.663 +/- 0.023 +/- 0.015 ps, where the first uncertainty is statistical and the second systematic. This new method results in a smaller systematic uncertainty in comparison to methods that use simulation to correct for the trigger bias.
Address [Aaltonen, T.; Mehtala, P.; Orava, R.; Osterberg, K.; Saarikko, H.; van Remortel, N.] Univ Helsinki, Dept Phys, Div High Energy Phys, FIN-00014 Helsinki, Finland
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 Medium
Area Expedition Conference
Notes ISI:000287393900001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 601
Permanent link to this record
 

 
Author Garcia-Recio, C.; Geng, L.S.; Nieves, J.; Salcedo, L.L.
Title Low-lying even-parity meson resonances and spin-flavor symmetry Type Journal Article
Year 2011 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 83 Issue 1 Pages 016007 - 30pp
Keywords
Abstract Based on a spin-flavor extension of chiral symmetry, a novel s-wave meson-meson interaction involving members of the rho nonet and of the pi octet is introduced, and its predictions are analyzed. The starting point is the SU(6) version of the SU(3)-flavor Weinberg-Tomozawa Lagrangian. SU(6) symmetry-breaking terms are then included to account for the physical meson masses and decay constants in a way that preserves (broken) chiral symmetry. Next, the T-matrix amplitudes are obtained by solving the Bethe-Salpeter equation in a coupled-channel scheme, and the poles are identified with their possible Particle Data Group counterparts. It is shown that most of the low-lying even-parity Particle Data Group meson resonances, especially in the J(P) = 0(+) and 1(+) sectors, can be classified according to multiplets of SU(6). The f(0)(1500), f(1)(1420), and some 0(+)(2(++)) resonances cannot be accommodated within this scheme, and thus they would be clear candidates to be glueballs or hybrids. Finally, we predict the existence of five exotic resonances (I >= 3/2 and/or vertical bar Y vertical bar = 2) with masses in the range of 1.4-1.6 GeV, which would complete the 27(1), 10(3), and 10(3)* multiplets of SU(3) circle times SU(2).
Address [Garcia-Recio, C.; Salcedo, L. L.] Univ Granada, Dept Fis Atom Mol & Nucl, E-18071 Granada, Spain
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 Medium
Area Expedition Conference
Notes ISI:000286765100008 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 585
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Author Donini, A.; Gomez-Cadenas, J.J.; Meloni, D.
Title The tau-contamination of the golden muon sample at the Neutrino Factory Type Journal Article
Year 2011 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 02 Issue 2 Pages 095 - 16pp
Keywords Neutrino Physics; Beyond Standard Model; CP violation
Abstract We study the contribution of nu(e) -> nu(tau) -> tau -> μtransitions to the wrong-sign muon sample of the golden channel of the Neutrino Factory. Muons from tau decays are not really a background, since they contain information from the oscillation signal, and represent a small fraction of the sample. However, if not properly handled they introduce serious systematic error, in particular if the detector/analysis are sensitive to muons of low energy. This systematic effect is particularly troublesome for large theta(13) >= 1 degrees and prevents the use of the Neutrino Factory as a precision facility for large theta(13). Such a systematic error disappears if the tau contribution to the golden muon sample is taken into account. The fact that the fluxes of the Neutrino Factory are exactly calculable permits the knowledge of the tau sample due to the nu(e) -> nu(tau) oscillation. We then compute the contribution to the muon sample arising from this sample in terms of the apparent muon energy. This requires the computation of a migration matrix M-ij which describes the contributions of the tau neutrinos of a given energy E-i, to the muon neutrinos of an apparent energy E-j. We demonstrate that applying M-ij to the data permits the full correction of the otherwise intolerable systematic error.
Address [Donini, A.] Univ Autonoma Madrid, CSIC, IFT, E-28049 Madrid, Spain, Email: andrea.donini@uam.es
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 Medium
Area Expedition Conference
Notes ISI:000287939200023 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 621
Permanent link to this record