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Author Aguilar, A.C.; Binosi, D.; Papavassiliou, J.
Title Dynamical equation of the effective gluon mass Type Journal Article
Year 2011 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 84 Issue 8 Pages 085026 - 19pp
Keywords
Abstract In this article, we derive the integral equation that controls the momentum dependence of the effective gluon mass in the Landau gauge. This is accomplished by means of a well-defined separation of the corresponding “one-loop dressed” Schwinger-Dyson equation into two distinct contributions, one associated with the mass and one with the standard kinetic part of the gluon. The entire construction relies on the existence of a longitudinally coupled vertex of nonperturbative origin, which enforces gauge invariance in the presence of a dynamical mass. The specific structure of the resulting mass equation, supplemented by the additional requirement of a positive-definite gluon mass, imposes a rather stringent constraint on the derivative of the gluonic dressing function, which is comfortably satisfied by the large-volume lattice data for the gluon propagator, both for SU(2) and SU(3). The numerical treatment of the mass equation, under some simplifying assumptions, is presented for the aforementioned gauge groups, giving rise to a gluon mass that is a nonmonotonic function of the momentum. Various theoretical improvements and possible future directions are briefly discussed.
Address [Aguilar, AC] Fed Univ ABC, CCNH, BR-09210170 Santo Andre, Brazil, Email: Arlene.Aguilar@ufabc.edu.br
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 WOS:000296889200007 Approved no
Is ISI (up) yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 814
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Author SciBooNE Collaboration (Kurimoto, Y. et al); Catala-Perez, J.; Gomez-Cadenas, J.J.; Sorel, M.
Title Measurement of inclusive neutral current pi(0) production on carbon in a few-GeV neutrino beam Type Journal Article
Year 2010 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 81 Issue 3 Pages 033004 - 18pp
Keywords
Abstract The SciBooNE Collaboration reports inclusive neutral current neutral pion production by a muon neutrino beam on a polystyrene target (C8H8). We obtain (7.7 +/- 0.5(stat) +/- 0.5(sys)) X 10(-2) as the ratio of the neutral current neutral pion production to total charged current cross section; the mean energy of neutrinos producing detected neutral pions is 1.1 GeV. The result agrees with the Rein-Sehgal model implemented in our neutrino interaction simulation program with nuclear effects. The spectrum shape of the pi(0) momentum and angle agree with the model. We also measure the ratio of the neutral current coherent pion production to total charged current cross section to be (0.7 +/- 0.4) X 10(-2).
Address [Kurimoto, Y.; Hiraide, K.; Kubo, H.; Matsuoka, K.; Nakajima, Y.; Nakaya, T.; Orme, D.; Otani, M.; Yokoyama, M.] Kyoto Univ, Dept Phys, Kyoto 6068502, Japan
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:000275069000015 Approved no
Is ISI (up) yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 492
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Author Aguilar, A.C.; Papavassiliou, J.
Title Gluon mass generation without seagull divergences Type Journal Article
Year 2010 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 81 Issue 3 Pages 034003 - 19pp
Keywords
Abstract Dynamical gluon mass generation has been traditionally plagued with seagull divergences, and all regularization procedures proposed over the years yield finite but scheme-dependent gluon masses. In this work we show how such divergences can be eliminated completely by virtue of a characteristic identity, valid in dimensional regularization. The ability to trigger the aforementioned identity hinges crucially on the particular Ansatz employed for the three-gluon vertex entering into the Schwinger-Dyson equation governing the gluon propagator. The use of the appropriate three-gluon vertex brings about an additional advantage: one obtains two separate (but coupled) integral equations, one for the effective charge and one for the gluon mass. This system of integral equations has a unique solution, which unambiguously determines these two quantities. Most notably, the effective charge freezes in the infrared, and the gluon mass displays power-law running in the ultraviolet, in agreement with earlier considerations.
Address [Aguilar, Arlene C.] Fed Univ ABC, CCNH, BR-09210170 Santo Andre, Brazil
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:000275069000024 Approved no
Is ISI (up) yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 493
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Author Mathieu, V.; Vento, V.
Title Pseudoscalar glueball and eta-eta ' mixing Type Journal Article
Year 2010 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 81 Issue 3 Pages 034004 - 12pp
Keywords
Abstract We have performed a dynamical analysis of the mixing in the pseudoscalar channel with the goal of understanding the existence and behavior of the pseudoscalar glueball. Our philosophy has not been to predict precise values of the glueball mass but to exploit an adequate effective theory to the point of breaking and to analyze which kind of mechanisms restore compatibility with data. Our study has led to analytical solutions which allow a clear understanding of the phenomena. The outcome of our calculation leads to a large mass glueball M-Theta > 2000 MeV, to a large glue content of the eta ', and to mixing angles in agreement with previous numerical studies.
Address [Mathieu, Vincent] Univ Mons, Serv Phys Nucl & Subnucl, Acad Univ Wallonie Bruxells, B-7000 Mons, Belgium, Email: vincent.mathieu@umons.ac.be
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:000275069000025 Approved no
Is ISI (up) yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 494
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Author Kochelev, N.I.; Vento, V.
Title Gluonic components of the pion and the transition form factor gamma*gamma* -> pi(0) Type Journal Article
Year 2010 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 81 Issue 3 Pages 034009 - 5pp
Keywords
Abstract We propose an effective Lagrangian for the coupling of the neutral pion with gluons whose strength is determined by a low-energy theorem. We calculate the contribution of the gluonic components arising from this interaction to the pion transition form factor gamma*gamma* -> pi(0) using the instanton liquid model to describe the quantum chromodynamics vacuum. We find that this contribution is large and might explain the anomalous behavior of the form factor at large virtuality of one of the photons, a feature which was recently discovered by the BABAR Collaboration.
Address [Kochelev, N. I.] Joint Inst Nucl Res, Bogoliubov Lab Theoret Phys, Dubna 141980, Moscow Region, Russia, Email: kochelev@theor.jinr.ru
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:000275069000030 Approved no
Is ISI (up) yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 495
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Author Gomez Dumm, D.; Roig, P.; Pich, A.; Portoles, J.
Title Hadron structure in tau -> KK pi nu(tau) decays Type Journal Article
Year 2010 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 81 Issue 3 Pages 034031 - 17pp
Keywords
Abstract We analyze the hadronization structure of both vector and axial-vector currents leading to tau -> KK pi nu(tau) decays. At leading order in the 1/N-C expansion, and considering only the contribution of the lightest resonances, we work out, within the framework of the resonance chiral Lagrangian, the structure of the local vertices involved in those processes. The couplings in the resonance theory are constrained by imposing the asymptotic behavior of vector and axial-vector spectral functions ruled by QCD. In this way we predict the hadron spectra and conclude that, contrary to previous assertions, the vector contribution dominates by far over the axial-vector one in all KK pi charge channels.
Address [Gomez Dumm, D.] Univ Nacl La Plata, IFLP, CONICET, Dpto Fis, RA-1900 La Plata, Argentina
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:000275069000052 Approved no
Is ISI (up) yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 496
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Author Cirigliano, V.; Jenkins, J.P.; Gonzalez-Alonso, M.
Title Semileptonic decays of light quarks beyond the Standard Model Type Journal Article
Year 2010 Publication Nuclear Physics B Abbreviated Journal Nucl. Phys. B
Volume 830 Issue 1-2 Pages 95-115
Keywords Semileptonic decays; CKM unitarity; Effective theory; Beyond the Standard Model
Abstract We describe non-standard contributions to semileptonic processes in a model independent way in terms of in SU(2)(L) x U(1)(Y) invariant effective lagrangian at the weak scale, front which we derive the low-energy effective lagrangian governing muon and beta decays. We find that the deviation from Cabibbo universality, Delta(CKM) equivalent to vertical bar V-ud vertical bar(2) + vertical bar V-us vertical bar(2) + vertical bar V-ub vertical bar(2) – 1, receives contributions from four effective operators. The phenomenological bound Delta(CKM) = (-1 +/- 6) x 10(-4) provides strong constraints on all four operators, corresponding to art effective scale Lambda > 11 TeV (90% CL). Depending on the operator, this constraint is at the same level or better then the Z pole observables. Conversely, precision electroweak constraints alone would allow universality violations as large as Delta(CKM) = -0.01 (90% CL). An observed Delta(CKM) not equal 0 at this level Could be explained in terms of a single four-fermion operator which is relatively poorly constrained by electroweak precision measurements.
Address [Cirigliano, Vincenzo; Jenkins, James P.; Gonzalez-Alonso, Martin] Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA, Email: cirigliano@lanl.gov
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 0550-3213 ISBN Medium
Area Expedition Conference
Notes ISI:000275150000003 Approved no
Is ISI (up) yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 497
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Author Lledo, M.A.; Sommovigo, L.
Title Torsion formulation of gravity Type Journal Article
Year 2010 Publication Classical and Quantum Gravity Abbreviated Journal Class. Quantum Gravity
Volume 27 Issue 6 Pages 065014 - 16pp
Keywords
Abstract We explain precisely what it means to have a connection with torsion as a solution of the Einstein equations. While locally the theory remains the same, the new formulation allows for topologies that would have been excluded in the standard formulation of gravity. In this formulation it is possible to couple arbitrary torsion to gauge fields without breaking the gauge invariance.
Address [Lledo, M. A.; Sommovigo, L.] Univ Valencia, Dept Fis Teor, E-46100 Valencia, Spain, Email: Maria.Lledo@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 0264-9381 ISBN Medium
Area Expedition Conference
Notes ISI:000275120600015 Approved no
Is ISI (up) yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 498
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Author Pierre Auger Collaboration (Abraham, J. et al); Pastor, S.
Title Trigger and aperture of the surface detector array of the Pierre Auger Observatory Type Journal Article
Year 2010 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A
Volume 613 Issue 1 Pages 29-39
Keywords Ultra high energy cosmic rays; Auger Observatory; Extensive air showers; Trigger; Exposure
Abstract The surface detector array of the Pierre Auger Observatory consists of 1600 water-Cherenkov detectors, for the study of extensive air showers (EAS) generated by ultra-high-energy cosmic rays. We describe the trigger hierarchy, from the identification of candidate showers at the level of a single detector, amongst a large background (mainly random single cosmic ray muons), up to the selection of real events and the rejection of random coincidences. Such trigger makes the surface detector array fully efficient for the detection of EAS with energy above 3 x 10(18) eV, for all zenith angles between 0 degrees and 60 degrees, independently of the position of the impact point and of the mass of the primary particle. In these range of energies and angles, the exposure of the surface array can be determined purely on the basis of the geometrical acceptance.
Address [Boncioli, D.; Delle Fratte, C.; Di Giulio, C.; Matthiae, G.; Petrinca, P.; Salina, G.; Verzi, V.] Univ Roma Tor Vergata, I-00173 Rome, Italy, Email: giorgio.matthiae@roma2.infn.it
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:000274772800005 Approved no
Is ISI (up) yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 499
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Author Pierre Auger Collaboration (Abreu, P. et al); Pastor, S.
Title Search for first harmonic modulation in the right ascension distribution of cosmic rays detected at the Pierre Auger Observatory Type Journal Article
Year 2011 Publication Astroparticle Physics Abbreviated Journal Astropart Phys.
Volume 34 Issue 8 Pages 627-639
Keywords Ultra-high energy cosmic rays; Large scale anisotropies; Pierre Auger Observatory
Abstract We present the results of searches for dipolar-type anisotropies in different energy ranges above 2.5 x 10(17) eV with the surface detector array of the Pierre Auger Observatory, reporting on both the phase and the amplitude measurements of the first harmonic modulation in the right-ascension distribution. Upper limits on the amplitudes are obtained, which provide the most stringent bounds at present, being below 2% at 99% C.L. for EeV energies. We also compare our results to those of previous experiments as well as with some theoretical expectations.
Address [Abreu, P.; Andringa, S.; Assis, P.; Brogueira, P.; Cazon, L.; Conceicao, R.; Goncalves, P.; Pimenta, M.; Santo, C. E.; Santos, E.; Tome, B.] LIP, P-1000 Lisbon, Portugal
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 Medium
Area Expedition Conference
Notes ISI:000288930200007 Approved no
Is ISI (up) yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 593
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