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Author Aparici, A.; Herrero-Garcia, J.; Rius, N.; Santamaria, A.
Title Neutrino masses from new generations Type Journal Article
Year 2011 Publication Journal of High Energy Physics Abbreviated Journal (up) J. High Energy Phys.
Volume 07 Issue 7 Pages 122
Keywords
Abstract We reconsider the possibility that Majorana masses for the three known neutrinos are generated radiatively by the presence of a fourth generation and one right-handed neutrino with Yukawa couplings and a Majorana mass term. We find that the observed light neutrino mass hierarchy is not compatible with low energy universality bounds in this minimal scenario, but all present data can be accommodated with five generations and two right-handed neutrinos. Within this framework, we explore the parameter space regions which are currently allowed and could lead to observable effects in neutrinoless double beta decay, mu-e conversion in nuclei and μ-> e gamma experiments. We also discuss the detection prospects at LHC.
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 1126-6708 ISBN Medium
Area Expedition Conference
Notes WOS:000293741500058 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ elepoucu @ Serial 759
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Author Boucenna, M.S.; Hirsch, M.; Morisi, S.; Peinado, E.; Taoso, M.; Valle, J.W.F.
Title Phenomenology of dark matter from A_4 flavor symmetry Type Journal Article
Year 2011 Publication Journal of High Energy Physics Abbreviated Journal (up) J. High Energy Phys.
Volume 05 Issue 5 Pages 037 - 20pp
Keywords Cosmology of Theories beyond the SM; Neutrino Physics; Discrete and Finite Symmetries
Abstract We investigate a model in which Dark Matter is stabilized by means of a Z(2) parity that results from the same non-abelian discrete flavor symmetry which accounts for the observed patter of neutrino mixing. In our A(4) example the standard model is extended by three extra Higgs doublets and the Z(2) parity emerges as a remnant of the spontaneous breaking of A(4) after electroweak symmetry breaking. We perform an analysis of the parameter space of the model consistent with electroweak precision tests, collider searches and perturbativity. We determine the regions compatible with the observed relic dark matter density and we present prospects for detection in direct as well as indirect Dark Matter search experiments.
Address [Boucenna, M. S.; Hirsch, M.; Morisi, S.; Peinado, E.; Taoso, M.; Valle, J. W. F.] Univ Valencia, CSIC, Inst Fis Corpuscular, AHEP Grp, E-46071 Valencia, Spain, Email: boucenna@ific.uv.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:000291364300037 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ elepoucu @ Serial 674
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Author Feroz, F.; Cranmer, K.; Hobson, M.; Ruiz de Austri, R.; Trotta, R.
Title Challenges of profile likelihood evaluation in multi-dimensional SUSY scans Type Journal Article
Year 2011 Publication Journal of High Energy Physics Abbreviated Journal (up) J. High Energy Phys.
Volume 06 Issue 6 Pages 042 - 23pp
Keywords Supersymmetry Phenomenology
Abstract Statistical inference of the fundamental parameters of supersymmetric theories is a challenging and active endeavor. Several sophisticated algorithms have been employed to this end. While Markov-Chain Monte Carlo (MCMC) and nested sampling techniques are geared towards Bayesian inference, they have also been used to estimate frequentist confidence intervals based on the profile likelihood ratio. We investigate the performance and appropriate configuration of MULTINEST, a nested sampling based algorithm, when used for profile likelihood-based analyses both on toy models and on the parameter space of the Constrained MSSM. We find that while the standard configuration previously used in the literarture is appropriate for an accurate reconstruction of the Bayesian posterior, the profile likelihood is poorly approximated. We identify a more appropriate MULTINEST configuration for profile likelihood analyses, which gives an excellent exploration of the profile likelihood (albeit at a larger computational cost), including the identification of the global maximum likelihood value. We conclude that with the appropriate configuration MULTINEST is a suitable tool for profile likelihood studies, indicating previous claims to the contrary are not well founded.
Address [Feroz, F; Hobson, M] Univ Cambridge, Cavendish Lab, Cambridge CB3 0HE, England, Email: f.feroz@mrao.cam.ac.uk
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 WOS:000293136500042 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 745
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Author Galli, P.; Goldstein, K.; Katmadas, S.; Perz, J.
Title First-order flows and stabilisation equations for non-BPS extremal black holes Type Journal Article
Year 2011 Publication Journal of High Energy Physics Abbreviated Journal (up) J. High Energy Phys.
Volume 06 Issue 6 Pages 070 - 28pp
Keywords Black Holes in String Theory; Supergravity Models
Abstract We derive a generalised form of flow equations for extremal static and rotating non-BPS black holes in four-dimensional ungauged N = 2 supergravity coupled to vector multiplets. For particular charge vectors, we give stabilisation equations for the scalars, analogous to the BPS case, describing full known solutions. Based on this, we propose a generic ansatz for the stabilisation equations, which surprisingly includes ratios of harmonic functions.
Address [Galli, P] Univ Valencia, Dept Fis Teor, E-46100 Burjassot, Valencia, Spain, Email: Pietro.Galli@ific.uv.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 WOS:000293136500070 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 746
Permanent link to this record
 

 
Author Donini, A.; Hernandez, P.; Lopez-Pavon, J.; Maltoni, M.
Title Minimal models with light sterile neutrinos Type Journal Article
Year 2011 Publication Journal of High Energy Physics Abbreviated Journal (up) J. High Energy Phys.
Volume 07 Issue 7 Pages 105
Keywords
Abstract We study the constraints imposed by neutrino oscillation experiments on the minimal extensions of the Standard Model (SM) with n(R) gauge singlet fermions (“right-handed neutrinos”), that can account for neutrino masses. We consider the most general coupling of the new fields to the SM fields, in particular those that break lepton number and we do not assume any a priori hierarchy in the mass parameters. We proceed to analyze these models starting from the lowest level of complexity, defined by the number of extra fermionic degrees of freedom. The simplest choice that has enough free parameters in principle (i.e. two mass differences and two angles) to explain the confirmed solar and atmospheric oscillations corresponds to n(R) = 1. This minimal choice is shown to be excluded by data. The next-to-minimal choice corresponds to n(R) = 2. We perform a systematic study of the full parameter space in the limit of degenerate Majorana masses by requiring that at least two neutrino mass differences correspond to those established by solar and atmospheric oscillations. We identify several types of spectra that can fit long-baseline reactor and accelerator neutrino oscillation data, but fail in explaining solar and/or atmospheric data. The only two solutions that survive are the expected seesaw and quasi-Dirac regions, for which we set lower and upper bounds respectively on the Majorana mass scale. Solar data from neutral current measurements provide essential information to constrain the quasi-Dirac region. The possibility to accommodate the LSND/MiniBoone and reactor anomalies, and the implications for neutrinoless double-beta decay and tritium beta decay are briefly discussed.
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 1126-6708 ISBN Medium
Area Expedition Conference
Notes WOS:000293741500041 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 760
Permanent link to this record