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Author Esteves, J.N.; Romao, J.C.; Hirsch, M.; Staub, F.; Porod, W.
Title Supersymmetric type-III seesaw mechanism: Lepton flavor violating decays and dark matter Type Journal Article
Year 2011 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 83 Issue 1 Pages 013003 - 21pp
Keywords
Abstract We study a supersymmetric version of the seesaw mechanism type III. The model consists of the minimal supersymmetric extension of the standard model particle content plus three copies of 24 superfields. The fermionic part of the SU(2) triplet contained in the 24 is responsible for the type-III seesaw, which is used to explain the observed neutrino masses and mixings. Complete copies of 24 are introduced to maintain gauge coupling unification. These additional states change the beta functions of the gauge couplings above the seesaw scale. Using minimal Supergravity boundary conditions, we calculate the resulting supersymmetric mass spectra at the electroweak scale using full 2-loop renormalization group equations. We show that the resulting spectrum can be quite different compared to the usual minimal Supergravity spectrum. We discuss how this might be used to obtain information on the seesaw scale from mass measurements. Constraints on the model space due to limits on lepton flavour violating decays are discussed. The main constraints come from the bounds on μ-> e gamma but there are also regions where the decay tau -> μgamma gives stronger constraints. We also calculate the regions allowed by the dark matter constraint. For the sake of completeness, we compare our results with those for the supersymmetric seesaw type II and, to some extent, with type I.
Address [Esteves, J. N.; Romao, J. C.] Inst Super Tecn, Dept Fis, P-1049001 Lisbon, Portugal, Email: joaomest@cftp.ist.utl.pt
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title (up)
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN Medium
Area Expedition Conference
Notes ISI:000286765100002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 583
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Author Aguilar, A.C.; Papavassiliou, J.
Title Chiral symmetry breaking with lattice propagators Type Journal Article
Year 2011 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 83 Issue 1 Pages 014013 - 17pp
Keywords
Abstract We study chiral symmetry breaking using the standard gap equation, supplemented with the infrared-finite gluon propagator and ghost dressing function obtained from large-volume lattice simulations. One of the most important ingredients of this analysis is the non-Abelian quark-gluon vertex, which controls the way the ghost sector enters into the gap equation. Specifically, this vertex introduces a numerically crucial dependence on the ghost dressing function and the quark-ghost scattering amplitude. This latter quantity satisfies its own, previously unexplored, dynamical equation, which may be decomposed into individual integral equations for its various form factors. In particular, the scalar form factor is obtained from an approximate version of the “one-loop dressed” integral equation, and its numerical impact turns out to be rather considerable. The detailed numerical analysis of the resulting gap equation reveals that the constituent quark mass obtained is about 300 MeV, while fermions in the adjoint representation acquire a mass in the range of (750-962) MeV.
Address [Aguilar, A. C.] 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 (up)
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN Medium
Area Expedition Conference
Notes ISI:000286765100005 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 584
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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 (up)
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 CDF Collaboration (Aaltonen, T. et al); Cabrera, S.
Title Measurement of the top quark mass and p(p)over-bar -> t(t)over-bar cross section in the all-hadronic mode with the CDF II detector Type Journal Article
Year 2010 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 81 Issue 5 Pages 052011 - 20pp
Keywords
Abstract We present a measurement of the top quark mass and of the top-antitop (t (t) over bar) pair production cross section using p (p) over bar data collected with the CDF II detector at the Tevatron Collider at the Fermi National Accelerator Laboratory and corresponding to an integrated luminosity of 2.9 fb(-1). We select events with six or more jets satisfying a number of kinematical requirements imposed by means of a neural-network algorithm. At least one of these jets must originate from a b quark, as identified by the reconstruction of a secondary vertex inside the jet. The mass measurement is based on a likelihood fit incorporating reconstructed mass distributions representative of signal and background, where the absolute jet energy scale ( JES) is measured simultaneously with the top quark mass. The measurement yields a value of 174.8 +/- 2.4(stat + JES)(-1.0)(+1.2)(syst) GeV/c(2), where the uncertainty from the absolute jet energy scale is evaluated together with the statistical uncertainty. The procedure also measures the amount of signal from which we derive a cross section, sigma(t (t$) over bar) = 7.2 +/- 0.5(stat) +/- 1.0(syst) +/- 0.4(lum) pb, for the measured values of top quark mass and JES.
Address [Aaltonen, T.; Anastassov, A.; 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 (up)
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN Medium
Area Expedition Conference
Notes ISI:000276194200019 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 290
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Author Antonelli, M. et al; Martinez-Vidal, F.; Pich, A.
Title Flavor physics in the quark sector Type Journal Article
Year 2010 Publication Physics Reports Abbreviated Journal Phys. Rep.
Volume 494 Issue 3-4 Pages 197-414
Keywords
Abstract In the past decade, one of the major challenges of particle physics has been to gain an in-depth understanding of the role of quark flavor. In this time frame, measurements and the theoretical interpretation of their results have advanced tremendously. A much broader understanding of flavor particles has been achieved; apart from their masses and quantum numbers, there now exist detailed measurements of the characteristics of their interactions allowing stringent tests of Standard Model predictions. Among the most interesting phenomena of flavor physics is the violation of the CP symmetry that has been subtle and difficult to explore. In the past, observations of CP violation were confined to neutral K mesons, but since the early 1990s, a large number of CP-violating processes have been studied in detail in neutral B mesons. In parallel, measurements of the couplings of the heavy quarks and the dynamics for their decays in large samples of K, D, and B mesons have been greatly improved in accuracy and the results are being used as probes in the search for deviations from the Standard Model. In the near future, there will be a transition from the current to a new generation of experiments; thus a review of the status of quark flavor physics is timely. This report is the result of the work of physicists attending the 5th CKM workshop, hosted by the University of Rome “La Sapienza”, September 9-13, 2008. It summarizes the results of the current generation of experiments that are about to be completed and it confronts these results with the theoretical understanding of the field which has greatly improved in the past decade.
Address [Cabibbo, N.; Cavoto, G.; Faccini, R.; Ferroni, F.; Franco, E.; Giagu, S.; Martinelli, G.; Rescigno, M.; Silvestrini, L.; Virto, J.] INFN Sez Roma, I-00185 Rome, Italy, Email: rfaccini@slac.stanford.edu
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title (up)
Series Volume Series Issue Edition
ISSN 0370-1573 ISBN Medium
Area Expedition Conference
Notes ISI:000282194400001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 374
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