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Author (down) Escribano, P.; Vicente, A.
Title Ultralight scalars in leptonic observables Type Journal Article
Year 2021 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 03 Issue 3 Pages 240 - 37pp
Keywords Beyond Standard Model; CP violation; Neutrino Physics
Abstract Many new physics scenarios contain ultralight scalars, states which are either exactly massless or much lighter than any other massive particle in the model. Axions and majorons constitute well-motivated examples of this type of particle. In this work, we explore the phenomenology of these states in low-energy leptonic observables. After adopting a model independent approach that includes both scalar and pseudoscalar interactions, we briefly discuss the current limits on the diagonal couplings to charged leptons and consider processes in which the ultralight scalar phi is directly produced, such as μ-> e phi, or acts as a mediator, as in tau -> μμmu. Contributions to the charged leptons magnetic and electric moments are studied as well.
Address [Escribano, Pablo; Vicente, Avelino] Univ Valencia, CSIC, Inst Fis Corpuscular, C Catedrat Jose Beltran 2, E-46980 Valencia, Spain, Email: pablo.escribano@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 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000635264700005 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 4769
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Author (down) Escribano, P.; Reig, M.; Vicente, A.
Title Generalizing the Scotogenic model Type Journal Article
Year 2020 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 07 Issue 7 Pages 097 - 25pp
Keywords Beyond Standard Model; Neutrino Physics; Renormalization Group
Abstract The Scotogenic model is an economical setup that induces Majorana neutrino masses at the 1-loop level and includes a dark matter candidate. We discuss a generalization of the original Scotogenic model with arbitrary numbers of generations of singlet fermion and inert doublet scalar fields. First, the full form of the light neutrino mass matrix is presented, with some comments on its derivation and with special attention to some particular cases. The behavior of the theory at high energies is explored by solving the Renormalization Group Equations.
Address [Escribano, Pablo; Reig, Mario; Vicente, Avelino] Univ Valencia, CSIC, Inst Fis Corpuscular, C Catedrat Jose Beltran 2, E-46980 Paterna, Valencia, Spain, Email: pablo.escribano@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 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000553119900003 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 4477
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Author (down) Escribano, P.; Hirsch, M.; Nava, J.; Vicente, A.
Title Observable flavor violation from spontaneous lepton number breaking Type Journal Article
Year 2022 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 01 Issue 1 Pages 098 - 31pp
Keywords Beyond Standard Model; Neutrino Physics; Global Symmetries
Abstract We propose a simple model of spontaneous lepton number violation with potentially large flavor violating decays, including the possibility that majoron emitting decays, such as μ-> e J, saturate the experimental bounds. In this model the majoron is a singlet-doublet admixture. It generates a type-I seesaw for neutrino masses and contains also a vector-like lepton. As a by-product, the model can explain the anomalous (g – 2)(mu), in parts of its parameter space, where one expects that the branching ratio of the Higgs to muons is changed with respect to Standard Model expectations. However, the explanation of the muon g – 2 anomaly would lead to tension with recent astrophysical bounds on the majoron coupling to muons.
Address [Escribano, Pablo; Hirsch, Martin; Nava, Jacopo; Vicente, Avelino] Univ Valencia, Inst Fis Corpuscular, CSIC, Parc Cient Paterna,C Catedrcit Jose Beltrcin 2, E-46980 Valencia, Spain, Email: pablo.escribano@ifis.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 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000744514600003 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 5084
Permanent link to this record
 
 
Author (down) Ellis, J.; Madigan, M.; Mimasu, K.; Sanz, V.; You, T.
Title Top, Higgs, diboson and electroweak fit to the Standard Model effective field theory Type Journal Article
Year 2021 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 04 Issue 4 Pages 279 - 78pp
Keywords Effective Field Theories; Beyond Standard Model; Higgs Physics
Abstract The search for effective field theory deformations of the Standard Model (SM) is a major goal of particle physics that can benefit from a global approach in the framework of the Standard Model Effective Field Theory (SMEFT). For the first time, we include LHC data on top production and differential distributions together with Higgs production and decay rates and Simplified Template Cross-Section (STXS) measurements in a global fit, as well as precision electroweak and diboson measurements from LEP and the LHC, in a global analysis with SMEFT operators of dimension 6 included linearly. We present the constraints on the coefficients of these operators, both individually and when marginalised, in flavour-universal and top-specific scenarios, studying the interplay of these datasets and the correlations they induce in the SMEFT. We then explore the constraints that our linear SMEFT analysis imposes on specific ultra-violet completions of the Standard Model, including those with single additional fields and low-mass stop squarks. We also present a model-independent search for deformations of the SM that contribute to between two and five SMEFT operator coefficients. In no case do we find any significant evidence for physics beyond the SM. Our underlying Fitmaker public code provides a framework for future generalisations of our analysis, including a quadratic treatment of dimension-6 operators.
Address [Ellis, John; Mimasu, Ken] Kings Coll London, Dept Phys, Theoret Particle Phys & Cosmol Grp, London WC2R 2LS, England, Email: john.ellis@cern.ch;
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 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000658918100001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4857
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Author (down) Edelhauser, L.; Porod, W.; Singh, R.K.
Title Spin discrimination in three-body decays Type Journal Article
Year 2010 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 08 Issue 8 Pages 053 - 31pp
Keywords Beyond Standard Model; Supersymmetric Standard Model
Abstract The identification of the correct model for physics beyond the Standard Model requires the determination of the spin of new particles. We investigate to which extent the spin of a new particle X can be identified in scenarios where it decays dominantly in three-body decays X -> f (f) over barY. Here we assume that Y is a candidate for dark matter and escapes direct detection at a high energy collider such as the LHC. We show that in the case that all intermediate particles are heavy, one can get information on the spins of X and Y at the LHC by exploiting the invariant mass distribution of the two standard model fermions. We develop a model-independent strategy to determine the spins without prior knowledge of the unknown couplings and test it in a series of Monte Carlo studies.
Address [Edelhaeuser, Lisa; Porod, Werner; Singh, Ritesh K.] Univ Wurzburg, Inst Theoret Phys & Astrophys, D-97074 Wurzburg, Germany, Email: ledelhaeuser@physik.uni-wuerzburg.de
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:000282368500014 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 355
Permanent link to this record
 
 
Author (down) Eberhardt, O.; Miralles, V.; Pich, A.
Title Constraints on coloured scalars from global fits Type Journal Article
Year 2021 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 10 Issue 10 Pages 123 - 23pp
Keywords Beyond Standard Model; Higgs Physics
Abstract We consider a simple extension of the electroweak theory, incorporating one SU(2)(L) doublet of colour-octet scalars with Yukawa couplings satisfying the principle of minimal flavour violation. Using the HEPfit package, we perform a global fit to the available data, including all relevant theoretical constraints, and extract the current bounds on the model parameters. Coloured scalars with masses below 1.05 TeV are already excluded, provided they are not fermiophobic. The mass splittings among the different (charged and CP-even and CP-odd neutral) scalars are restricted to be smaller than 20 GeV. Moreover, for scalar masses smaller than 1.5 TeV, the Yukawa coupling of the coloured scalar multiplet to the top quark cannot exceed the one of the SM Higgs doublet by more than 80%. These conclusions are quite generic and apply in more general frameworks (without fine tunings). The theoretical requirements of perturbative unitarity and vacuum stability enforce relevant constraints on the quartic scalar potential parameters that are not yet experimentally tested.
Address [Eberhardt, Otto; Miralles, Victor; Pich, Antonio] Inst Fis Corpuscular, Parque Cient,C Catedrat Jose Beltran 2, E-46980 Paterna, Spain, Email: otto.eberhardt.physics@gmail.com;
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 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000708483600001 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 5006
Permanent link to this record
 
 
Author (down) Durieux, G.; Perello, M.; Vos, M.; Zhang, C.
Title Global and optimal probes for the top-quark effective field theory at future lepton colliders Type Journal Article
Year 2018 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 10 Issue 10 Pages 168 - 68pp
Keywords Beyond Standard Model; Effective Field Theories; Heavy Quark Physics
Abstract We study the sensitivity to physics beyond the standard model of precise top-quark pair production measurements at future lepton colliders. A global effective-field-theory approach is employed, including all ten dimension-six operators of the Warsaw basis which involve a top-quark and give rise to tree-level amplitudes that interfere with standard-model e+e-tt ones in the limit of vanishing b-quark mass. Four-fermion and CP-violating contributions are taken into account. Circular-collider-, ILC- and CLIC-like benchmark run scenarios are examined. We compare the constraining power of various observables to a set of statistically optimal ones which maximally exploit the information contained in the fully differential bW+ distribution. The enhanced sensitivity gained on the linear contributions of dimension-six operators leads to bounds that are insensitive to quadratic ones. Even with statistically optimal observables, two centre-of-mass energies are required for constraining simultaneously two- and four-fermion operators. The impact of the centre-of-mass energy lever arm is discussed, that of beam polarization as well. A realistic estimate of the precision that can be achieved in ILC- and CLIC-like operating scenarios yields individual limits on the electroweak couplings of the top quark that are one to three orders of magnitude better than constraints set with Tevatron and LHC run I data, and three to two hundred times better than the most optimistic projections made for the high-luminosity phase of the LHC. Clean global constraints can moreover be obtained at lepton colliders, robustly covering the multidimensional effective-field-theory space with minimal model dependence.
Address [Durieux, Gauthier] DESY, Notkestr 85, D-22607 Hamburg, Germany, Email: gauthier.durieux@desy.de;
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 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000448812600001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3786
Permanent link to this record
 
 
Author (down) Duarte, L.; Gonzalez-Sprinberg, G.A.; Vidal, J.
Title Top quark anomalous tensor couplings in the two-Higgs-doublet models Type Journal Article
Year 2013 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 11 Issue 11 Pages 114 - 21pp
Keywords Beyond Standard Model; Standard Model
Abstract We compute the one loop right and left anomalous tensor couplings (g(R) and g(L), respectively) for the top quark, in the aligned two-Higgs-doublet model. They are the magnetic-like couplings in the most general parameterization of the tbW vertex. We find that the aligned two-Higgs doublet model, that includes as particular cases some of the most studied extensions of the Higgs sector, introduces new electroweak contribution's and provides theoretical predictions that are very sensitive to both new scalar masses and the neutral scalar mixing angle. For a largo area in the parameters space we obtain significant deviations in both the real and the imaginary parts of the couplings gR and gL, compared to the predictions given by the electroweak sector of the Standard Model. The most important ones are those involving the imaginary part of the left coupling g(L) and the real part of the right coupling gR. The real part of g(L), and the imaginary part of gR also show an important sensitivity to new physics scenarios. The model can also account for new CP violation effects via the introduction of complex alignment parameters that have important consequences on the values for the imaginary parts of the couplings. The top anomalous tensor couplings will be measured at the LHC and at future colliders providing a complementary insight on new physics, independent from the bounds in top decays coming from B physics and b -> s gamma.
Address [Duarte, Lucia] Univ Republica, Fac Ingn, Inst Fis, Montevideo 11000, Uruguay, Email: lucia@fisica.edu.uy;
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 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000327092900014 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1650
Permanent link to this record
 
 
Author (down) Donini, A.; Hernandez, P.; Lopez-Pavon, J.; Maltoni, M.; Schwetz, T.
Title The minimal 3+2 neutrino model versus oscillation anomalies Type Journal Article
Year 2012 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 07 Issue 7 Pages 161 - 20pp
Keywords Neutrino Physics; Beyond Standard Model
Abstract We study the constraints imposed by neutrino oscillation experiments on the minimal extension of the Standard Model that can explain neutrino masses, which requires the addition of just two singlet Weyl fermions. The most general renormalizable couplings of this model imply generically four massive neutrino mass eigenstates while one remains massless: it is therefore a minimal 3+2 model. The possibility to account for the confirmed solar, atmospheric and long-baseline oscillations, together with the LSND/MiniBooNE and reactor anomalies is addressed. We find that the minimal model can fit oscillation data including the anomalies better than the standard 3 nu model and similarly to the 3 + 2 phenomenological models, even though the number of free parameters is much smaller than in the latter. Accounting for the anomalies in the minimal model favours a normal hierarchy of the light states and requires a large reactor angle, in agreement with recent measurements. Our analysis of the model employs a new parametrization of seesaw models that extends the Casas-Ibarra one to regimes where higher order corrections in the light-heavy mixings are significant.
Address [Donini, A.; Hernandez, P.] Univ Valencia, Inst Fis Corpuscular, CSIC, E-46071 Valencia, 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 WOS:000307299800039 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1161
Permanent link to this record
 
 
Author (down) 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