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Author Gonzalez Felipe, R.; Serodio, H.; Silva, J.P.
Title Neutrino masses and mixing in A(4) models with three Higgs doublets Type Journal Article
Year 2013 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 88 Issue 1 Pages 015015 - 10pp
Keywords
Abstract We study neutrino masses and mixing in the context of flavor models with A(4) symmetry, three scalar doublets in the triplet representation, and three lepton families. We show that there is no representation assignment that yields a dimension-5 mass operator consistent with experiment. We then consider a type-I seesaw with three heavy right-handed neutrinos, explaining in detail why it fails, and allowing us to show that agreement with the present neutrino oscillation data can be recovered with the inclusion of dimension-3 heavy neutrino mass terms that break softly the A(4) symmetry.
Address [Felipe, R. Gonzalez; Silva, Joao P.] Inst Super Engn Lisboa, P-1959007 Lisbon, Portugal, Email: ricardo.felipe@ist.utl.pt;
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language (up) 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:000321737600009 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1499
Permanent link to this record
 
 
Author Ghosh, P.; Lopez-Fogliani, D.E.; Mitsou, V.A.; Muñoz, C.; Ruiz de Austri, R.
Title Probing the mu-from-nu supersymmetric standard model with displaced multileptons from the decay of a Higgs boson at the LHC Type Journal Article
Year 2013 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 88 Issue 1 Pages 015009 - 6pp
Keywords
Abstract The "mu from nu'' supersymmetric standard model (mu nu SSM) cures the μproblem and concurrently reproduces measured neutrino data by using a set of usual right-handed neutrino superfields. Recently, the LHC has revealed the first scalar boson which naturally makes it tempting to test μnu SSM in the light of this new discovery. We show that this new scalar, while decaying to a pair of unstable long-lived neutralinos, can lead to a distinct signal with nonprompt multileptons. With concomitant collider analysis we show that this signal provides an intriguing signature of the model, pronounced with light neutralinos. Evidence of this signal is well envisaged with sophisticated displaced vertex analysis, which deserves experimental attention.
Address [Ghosh, Pradipta; Munoz, Carlos] Univ Autonoma Madrid, Dept Fis Teor, E-28049 Madrid, Spain, Email: pradipta.ghosh@uam.es;
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language (up) 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:000321671700008 Approved no
Is ISI yes International Collaboration
Call Number IFIC @ pastor @ Serial 1505
Permanent link to this record
 
 
Author Forero, D.V.; Morisi, S.; Romao, J.C.; Valle, J.W.F.
Title Neutrino mixing with revamped A(4) flavor symmetry Type Journal Article
Year 2013 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 88 Issue 1 Pages 016003 - 7pp
Keywords
Abstract We suggest a minimal extension of the simplest A(4) flavor model that can induce a nonzero theta(13) value, as required by recent neutrino oscillation data from reactors and accelerators. The predicted correlation between the atmospheric mixing angle theta(23) and the magnitude of theta(13) leads to an allowed region substantially smaller than indicated by neutrino-oscillation global fits. Moreover, the scheme correlates CP violation in neutrino oscillations with the octant of the atmospheric mixing parameter theta(23) in such a way that, for example, maximal mixing necessarily violates CP. We briefly comment on other phenomenological features of the model.
Address [Forero, D. V.; Romao, J. C.] Univ Tecn Lisboa, Dept Fis, Inst Super Tecn, P-1049001 Lisbon, Portugal, Email: dvanegas@ific.uv.es;
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language (up) 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:000321125000011 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1507
Permanent link to this record
 
 
Author Aguilar, A.C.; Ibañez, D.; Papavassiliou, J.
Title Ghost propagator and ghost-gluon vertex from Schwinger-Dyson equations Type Journal Article
Year 2013 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 87 Issue 11 Pages 114020 - 14pp
Keywords
Abstract We study an approximate version of the Schwinger-Dyson equation that controls the nonperturbative behavior of the ghost-gluon vertex in the Landau gauge. In particular, we focus on the form factor that enters in the dynamical equation for the ghost dressing function, in the same gauge, and derive its integral equation, in the “one-loop dressed” approximation. We consider two special kinematic configurations, which simplify the momentum dependence of the unknown quantity; in particular, we study the soft gluon case and the well-known Taylor limit. When coupled with the Schwinger-Dyson equation of the ghost dressing function, the contribution of this form factor provides considerable support to the relevant integral kernel. As a consequence, the solution of this coupled system of integral equations furnishes a ghost dressing function that reproduces the standard lattice results rather accurately, without the need to artificially increase the value of the gauge coupling.
Address [Aguilar, A. C.] Univ Estadual Campinas, Inst Phys Gleb Wataghin, BR-13083859 Sao Paulo, Brazil
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language (up) 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:000321001100003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1508
Permanent link to this record
 
 
Author Rinaldi, M.; Scopetta, S.; Vento, V.
Title Double parton correlations in constituent quark models Type Journal Article
Year 2013 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 87 Issue 11 Pages 114021 - 9pp
Keywords
Abstract Double parton correlations, having effects on the double parton scattering processes occurring in high-energy hadron-hadron collisions, for example at the LHC, are studied in the valence quark region by means of constituent quark models. In this framework, two particle correlations are present without any additional prescription, at variance with what happens, for example, in independent particle models, such as the MIT bag model in its simplest version. From the present analysis, conclusions similar to the ones obtained recently in a modified version of the bag model can be drawn: correlations in the longitudinal momenta of the active quarks are found to be sizable, while those in transverse momentum are much smaller. However, the framework used allows us to understand clearly the dynamical origin of the correlations. In particular, it is shown that the small size of the correlations in transverse momentum is a model-dependent result, which would not occur if models with sizable quark orbital angular momentum were used to describe the proton. Our analysis permits us, therefore, to clarify the dynamical origin of the double parton correlations and to establish which, among the features of the results, are model independent. The possibility of testing the studied effects experimentally is discussed.
Address [Rinaldi, M.; Scopetta, S.] Univ Perugia, Dipartimento Fis, I-06100 Perugia, Italy, Email: matteo.rinaldi@pg.infn.it;
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language (up) 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:000321001100004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1509
Permanent link to this record
 
 
Author Morisi, S.; Nebot, M.; Patel, K.M.; Peinado, E.; Valle, J.W.F.
Title Quark-lepton mass relation and CKM mixing in an A(4) extension of the minimal supersymmetric standard model Type Journal Article
Year 2013 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 88 Issue 3 Pages 036001 - 8pp
Keywords
Abstract An interesting mass relation between down-type quarks and charged leptons has been recently predicted within a supersymmetric SU(3)(c) circle times SU(2)(L) circle times U(1)(Y) model based on the A(4) flavor symmetry. Here we propose a simple extension which provides an adequate full description of the quark sector. By adding a pair of vectorlike up quarks, we show how the CKM entries V-ub, V-cb, V-td and V-ts arise from deviations of the unitarity. We perform an analysis including the most relevant observables in the quark sector, such as oscillations and rare decays of kaons, B-d and B-s mesons. In the lepton sector, the model predicts an inverted hierarchy for the neutrino masses, leading to a potentially observable rate of neutrinoless double beta decay.
Address [Morisi, S.] Univ Wurzburg, Inst Theoret Phys & Astrophys, D-97074 Wurzburg, Germany, Email: stefano.morisi@gmail.com;
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language (up) 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:000322725800002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1520
Permanent link to this record
 
 
Author Helo, J.C.; Kovalenko, S.G.; Hirsch, M.; Pas, H.
Title Neutrinoless double beta decay and lepton number violation at the LHC Type Journal Article
Year 2013 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 88 Issue 1 Pages 011901 - 5pp
Keywords
Abstract We compare the discovery potential of the LHC for lepton number violating (LNV) signals with the sensitivity of current and future double beta decay experiments, assuming 0 nu beta beta decay is dominated by heavy particle exchange. We consider charged scalar, leptoquark and diquark mechanisms of 0 nu beta beta decay, covering the 0 nu beta beta decay operators with both, the smallest and largest, possible rates. We demonstrate, if 0 nu beta beta decay were found with a half-life below 10(26)-10(27) years a positive signal should show up at the LHC, except for some particular cases of the leptoquark mechanism, and vice versa, if the LHC does not find any hints for LNV, a “short-range” explanation for a finite 0 nu beta beta decay half-life will be ruled out in most cases. We argue, if a positive LNV signal were found at the LHC, it is possible to identify the dominant contribution to 0 nu beta beta. Two different kinds of observables which could provide such “model discriminating” power are discussed: different invariant mass peaks and the charge asymmetry.
Address [Helo, J. C.; Kovalenko, S. G.] Univ Tecn Federico Santa Maria, Ctr Cient Tecnol Valparaiso, Valparaiso, Chile, Email: juan.heloherrera@gmail.com;
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language (up) 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:000322225900001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1523
Permanent link to this record
 
 
Author Salvatelli, V.; Marchini, A.; Lopez-Honorez, L.; Mena, O.
Title New constraints on coupled dark energy from the Planck satellite experiment Type Journal Article
Year 2013 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 88 Issue 2 Pages 023531 - 9pp
Keywords
Abstract We present new constraints on coupled dark energy from the recent measurements of the cosmic microwave background anisotropies from the Planck satellite mission. We found that a coupled dark energy model is fully compatible with the Planck measurements, deriving a weak bound on the dark matter-dark energy coupling parameter xi = -0.49(-0.31)(+0.19) at 68% C.L. Moreover if Planck data are fitted to a coupled dark energy scenario, the constraint on the Hubble constant is relaxed to H-0 = 72.1(-2.3)(+3.2) km/s/Mpc, solving the tension with the Hubble Space Telescope (HST) value. We show that a combined PLANCK + HST analysis provides significant evidence for coupled dark energy finding a nonzero value for the coupling parameter xi, with -0.90 < xi < -0.22 at 95% C.L. We also consider the combined constraints from the Planck data plus the baryon acoustic oscillation measurements of the 6dF Galaxy Survey, the Sloan Digital Sky Survey and the Baron Oscillation Spectroscopic Survey.
Address [Salvatelli, Valentina; Marchini, Andrea] Univ Roma La Sapienza, Dept Phys, I-00185 Rome, Italy
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language (up) 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:000322216900003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1524
Permanent link to this record
 
 
Author Ozpineci, A.; Xiao, C.W.; Oset, E.
Title Hidden beauty molecules within the local hidden gauge approach and heavy quark spin symmetry Type Journal Article
Year 2013 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 88 Issue 3 Pages 034018 - 14pp
Keywords
Abstract Using a coupled channel unitary approach, combining the heavy quark spin symmetry and the dynamics of the local hidden gauge, we investigate the meson-meson interaction with hidden beauty and obtain several new states. Both I = 0 and I = 1 states are analyzed, and it is shown that in the I = 1 sector, the interactions are too weak to create any bound states within our framework. In total, we predict with confidence the existence of six bound states and six more possible weakly bound states. The existence of these weakly bound states depends on the influence of the coupled channel effects.
Address [Ozpineci, A.] Univ Valencia, Dept Fis Teor, Valencia 46071, Spain
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language (up) 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:000322902200002 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 1545
Permanent link to this record
 
 
Author BABAR Collaboration (Lees, J.P. et al); Martinez-Vidal, F.; Oyanguren, A.
Title Evidence of B+ -> tau(+)nu decays with hadronic B tags Type Journal Article
Year 2013 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 88 Issue 3 Pages 031102 - 9pp
Keywords
Abstract We present a search for the decay B+ -> tau(+)nu using 467.8 x 10(6) B (B) over bar pairs collected at the Upsilon(4S) resonance with the BABAR detector at the SLAC PEP-II B-Factory. We select a sample of events with one completely reconstructed B- in the hadronic decay mode (B- -> D-(*X-)0(-) and B- -> J/psi X-). We examine the rest of the event to search for a B+ -> tau(+)nu decay. We identify the tau(+) lepton in the following modes: tau(+) -> e(+)nu(nu) over bar, tau(+) -> mu(+)nu(nu) over bar, tau(+) -> pi(+)(nu) over bar and tau(+) -> rho(+)(nu) over bar. We find an excess of events with respect to the expected background, which excludes the null signal hypothesis at the level of 3.8 sigma (including systematic uncertainties) and corresponds to a branching fraction value of B(B+ -> tau(+)nu) = (1.83(-0.49)(+0.53)(stat) +/- 0.24(syst)) x 10(-4).
Address [Lees, J. P.; Poireau, V.; Tisserand, V.] Univ Savoie, CNRS IN2P3, Lab Annecy le Vieux Phys Particules LAPP, F-74941 Annecy Le Vieux, France
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language (up) 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:000322916300001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1547
Permanent link to this record