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Author Della Morte, M.; Hernandez, P.
Title A non-perturbative study of massive gauge theories Type Journal Article
Year 2013 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 11 Issue 11 Pages 213 - 20pp
Keywords
Abstract We consider a non-perturbative formulation of an SU(2) massive gauge theory on a space-time lattice, which is also a discretised gauged non-linear chiral model. The lattice model is shown to have an exactly conserved global SU(2) symmetry. If a scaling region for the lattice model exists and the lightest degrees of freedom are spin one vector particles with the same quantum numbers as the conserved current, we argue that the most general effective theory describing their low-energy dynamics must be a massive gauge theory. We present results of a exploratory numerical simulation of the model and find indications for the presence of a scaling region where both a triplet vector and a scalar remain light.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
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Notes Approved no
Is ISI yes International Collaboration (down) yes
Call Number IFIC @ pastor @ Serial 1765
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Author Hernandez, P.; Kekic, M.; Lopez-Pavon, J.
Title N_eff in low-scale seesaw models versus the lightest neutrino mass Type Journal Article
Year 2014 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 90 Issue 6 Pages 065033 - 12pp
Keywords
Abstract We evaluate the contribution to N_eff of the extra sterile states in low-scale type I seesaw models (with three extra sterile states). We explore the full parameter space and find that at least two of the heavy states always reach thermalization in the early Universe, while the third one might not thermalize provided the lightest neutrino mass is below O(10(-3) eV). Constraints from cosmology therefore severely restrict the spectra of heavy states in the range 1 eV-100 MeV. The implications for neutrinoless double beta decay are also discussed.
Address [Hernandez, P.; Kekic, M.] Univ Valencia, IFIC CSIC, E-46071 Valencia, Spain, Email: m.pilar.hernandez@uv.es;
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:000344108100004 Approved no
Is ISI yes International Collaboration (down) yes
Call Number IFIC @ pastor @ Serial 2001
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Author Vincent, A.C.; Fernandez Martinez, E.; Hernandez, P.; Mena, O.; Lattanzi, M.
Title Revisiting cosmological bounds on sterile neutrinos Type Journal Article
Year 2015 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 04 Issue 4 Pages 006 - 23pp
Keywords particle physics – cosmology connection; cosmological neutrinos; cosmology of theories beyond the SM
Abstract We employ state-of-the art cosmological observables including supernova surveys and BAO information to provide constraints on the mass and mixing angle of a non-resonantly produced sterile neutrino species, showing that cosmology can effectively rule out sterile neutrinos which decay between BBN and the present day. The decoupling of an additional heavy neutrino species can modify the time dependence of the Universe's expansion between BBN and recombination and, in extreme cases, lead to an additional matter-dominated period; while this could naively lead to a younger Universe with a larger Hubble parameter, it could later be compensated by the extra radiation expected in the form of neutrinos from sterile decay. However, recombination-era observables including the Cosmic Microwave Background (CMB), the shift parameter R-CMB and the sound horizon r(s) from Baryon Acoustic Oscillations (BAO) severely constrain this scenario. We self-consistently include the full time-evolution of the coupled sterile neutrino and standard model sectors in an MCMC, showing that if decay occurs after BBN, the sterile neutrino is essentially bounded by the constraint sin(2) theta less than or similar to 0.026(m(s)/eV)(-2).
Address [Vincent, Aaron C.] Univ Durham, Dept Phys, IPPP, Durham DH1 3LE, England, Email: aaron.vincent@durham.ac.uk;
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 1475-7516 ISBN Medium
Area Expedition Conference
Notes WOS:000355742500007 Approved no
Is ISI yes International Collaboration (down) yes
Call Number IFIC @ pastor @ Serial 2261
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Author Hernandez, P.; Kekic, M.; Lopez-Pavon, J.; Racker, J.; Rius, N.
Title Leptogenesis in GeV-scale seesaw models Type Journal Article
Year 2015 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 10 Issue 10 Pages 067 - 34pp
Keywords Beyond Standard Model; Cosmology of Theories beyond the SM; Neutrino Physics; CP violation
Abstract We revisit the production of leptonic asymmetries in minimal extensions of the Standard Model that can explain neutrino masses, involving extra singlets with Majorana masses in the GeV scale. We study the quantum kinetic equations both analytically, via a perturbative expansion up to third order in the mixing angles, and numerically. The analytical solution allows us to identify the relevant CP invariants, and simplifies the exploration of the parameter space. We find that sizeable lepton asymmetries are compatible with non-degenerate neutrino masses and measurable active-sterile mixings.
Address [Hernandez, P.; Kekic, M.; Racker, J.; Rius, N.] Univ Valencia, Inst Fis Corpuscular, E-46071 Valencia, Spain, Email: m.pilar.hernandez@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:000363555500002 Approved no
Is ISI yes International Collaboration (down) yes
Call Number IFIC @ pastor @ Serial 2425
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Author Gago, A.M.; Hernandez, P.; Jones-Perez, J.; Losada, M.; Moreno Briceño, A.
Title Probing the Type I Seesaw mechanism with displaced vertices at the LHC Type Journal Article
Year 2015 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 75 Issue 10 Pages 470 - 10pp
Keywords
Abstract The observation of Higgs decays into heavy neutrinos would be strong evidence for new physics associated to neutrino masses. In this work we propose a search for such decays within the Type I Seesaw model in the few-GeV mass range via displaced vertices. Using 300 fb(-1) of integrated luminosity, at 13 TeV, we explore the region of parameter space where such decays are measurable. We show that, after imposing pseudorapidity cuts, there still exists a region where the number of events is larger than O(10). We also find that conventional triggers can greatly limit the sensitivity of our signal, so we display several relevant kinematical distributions which might aid in the optimization of a dedicated trigger selection.
Address [Gago, Alberto M.; Jones-Perez, Joel] Pontificia Univ Catolica Peru, Dept Ciencias, Secc Fis, Lima, Peru, Email: agago@pucp.edu.pe;
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 1434-6044 ISBN Medium
Area Expedition Conference
Notes WOS:000366309300005 Approved no
Is ISI yes International Collaboration (down) yes
Call Number IFIC @ pastor @ Serial 2498
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Author Hernandez, P.; Kekic, M.; Lopez-Pavon, J.; Racker, J.; Salvado, J.
Title Testable baryogenesis is in seesaw models Type Journal Article
Year 2016 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 08 Issue 8 Pages 157 - 29pp
Keywords Cosmology of Theories beyond the SM; CP violation; Neutrino Physics; Beyond Standard Model
Abstract We revisit the production of baryon asymmetries in the minimal type I seesaw model with heavy Majorana singlets in the GeV range. In particular we include “washout” effects from scattering processes with gauge bosons, Higgs decays and inverse decays, besides the dominant top scatterings. We show that in the minimal model with two singlets, and for an inverted light neutrino ordering, future measurements from SHiP and neutrinoless double beta decay could in principle provide sufficient information to predict the matter-antimatter asymmetry in the universe. We also show that SHiP measurements could provide very valuable information on the PMNS CP phases.
Address [Hernandez, P.; Kekic, M.; Racker, J.; Salvado, J.] Univ Valencia, Inst Fis Corpuscular, Edificio Inst Invest,Catedrat Jose Beltran 2, Valencia 46980, Spain, Email: m.pilar.hernandez@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:000382398000004 Approved no
Is ISI yes International Collaboration (down) yes
Call Number IFIC @ pastor @ Serial 2787
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Author Alekhin, S. et al; Hernandez, P.
Title A facility to search for hidden particles at the CERN SPS: the SHiP physics case Type Journal Article
Year 2016 Publication Reports on Progress in Physics Abbreviated Journal Rep. Prog. Phys.
Volume 79 Issue 12 Pages 124201 - 137pp
Keywords beyond the standard model physics; intensity frontier experiment; hidden sectors; heavy neutral leptons; dark photons
Abstract This paper describes the physics case for a new fixed target facility at CERN SPS. The SHiP (search for hidden particles) experiment is intended to hunt for new physics in the largely unexplored domain of very weakly interacting particles with masses below the Fermi scale, inaccessible to the LHC experiments, and to study tau neutrino physics. The same proton beam setup can be used later to look for decays of tau-leptons with lepton flavour number non-conservation, tau -> 3 μand to search for weakly-interacting sub-GeV dark matter candidates. We discuss the evidence for physics beyond the standard model and describe interactions between new particles and four different portals-scalars, vectors, fermions or axion-like particles. We discuss motivations for different models, manifesting themselves via these interactions, and how they can be probed with the SHiP experiment and present several case studies. The prospects to search for relatively light SUSY and composite particles at SHiP are also discussed. We demonstrate that the SHiP experiment has a unique potential to discover new physics and can directly probe a number of solutions of beyond the standard model puzzles, such as neutrino masses, baryon asymmetry of the Universe, dark matter, and inflation.
Address [Alekhin, Sergey] DESY, Platanenallee 6, D-15738 Zeuthen, Germany, Email: oleg.ruchayskiy@cern.ch
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 0034-4885 ISBN Medium
Area Expedition Conference
Notes WOS:000387025400001 Approved no
Is ISI yes International Collaboration (down) yes
Call Number IFIC @ pastor @ Serial 2852
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Author Caputo, A.; Hernandez, P.; Kekic, M.; Lopez-Pavon, J.; Salvado, J.
Title The seesaw path to leptonic CP violation Type Journal Article
Year 2017 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 77 Issue 4 Pages 258 - 7pp
Keywords
Abstract Future experiments such as SHiP and highintensity e(+)e(-) colliders will have a superb sensitivity to heavy Majorana neutrinos with masses below M-Z. We show that the measurement of the mixing to electrons and muons of one such state could establish the existence of CP violating phases in the neutrino mixing matrix, in the context of low-scale seesaw models. We quantify in the minimal model the CP reach of these future experiments, and demonstrate that CP violating phases in the mixing matrix could be established at 5 sigma CL in a very significant fraction of parameter space.
Address [Caputo, A.; Hernandez, P.; Kekic, M.; Salvado, J.] Univ Valencia, Inst Fis Corpuscular, Edificio Inst Invest,Catedrat Jose Beltran 2, Paterna 46980, Spain, Email: andrea.caputo@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 1434-6044 ISBN Medium
Area Expedition Conference
Notes WOS:000400079300002 Approved no
Is ISI yes International Collaboration (down) yes
Call Number IFIC @ pastor @ Serial 3111
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Author Caputo, A.; Hernandez, P.; Lopez-Pavon, J.; Salvado, J.
Title The seesaw portal in testable models of neutrino masses Type Journal Article
Year 2017 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 06 Issue 6 Pages 112 - 20pp
Keywords Beyond Standard Model; Neutrino Physics
Abstract A Standard Model extension with two Majorana neutrinos can explain the measured neutrino masses and mixings, and also account for the matter-antimatter asymmetry in a region of parameter space that could be testable in future experiments. The testability of the model relies to some extent on its minimality. In this paper we address the possibility that the model might be extended by extra generic new physics which we parametrize in terms of a low-energy effective theory. We consider the effects of the operators of the lowest dimensionality, d = 5, and evaluate the upper bounds on the coefficients so that the predictions of the minimal model are robust. One of the operators gives a new production mechanism for the heavy neutrinos at LHC via higgs decays. The higgs can decay to a pair of such neutrinos that, being long-lived, leave a powerful signal of two displaced vertices. We estimate the LHC reach to this process.
Address [Caputo, A.; Hernandez, P.; Salvado, J.] Univ Valencia, Inst Fis Corpusc, Catedrat Jose Beltran 2, Valencia 46980, Spain, Email: andrea.caputo@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:000404625300005 Approved no
Is ISI yes International Collaboration (down) yes
Call Number IFIC @ pastor @ Serial 3196
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Author Chun, E.J.; Cvetic, G.; Dev, P.S.B.; Drewes, M.; Fong, C.S.; Garbrecht, B.; Hambye, T.; Harz, J.; Hernandez, P.; Kim, C.S.; Molinaro, E.; Nardi, E.; Racker, J.; Rius, N.; Zamora-Saa, J.
Title Probing leptogenesis Type Journal Article
Year 2018 Publication International Journal of Modern Physics A Abbreviated Journal Int. J. Mod. Phys. A
Volume 33 Issue 5-6 Pages 1842005 - 99pp
Keywords Neutrino interactions; nonstandard-model neutrinos; right-handed neutrinos; extensions of electroweak gauge sector; supersymmetric models
Abstract The focus of this paper lies on the possible experimental tests of leptogenesis scenarios. We consider both leptogenesis generated from oscillations, as well as leptogenesis from out-of-equilibrium decays. As the Akhmedov-Rubakov-Smirnov (ARS) mechanism allows for heavy neutrinos in the GeV range, this opens up a plethora of possible experimental tests, e.g. at neutrino oscillation experiments, neutrinoless double beta decay, and direct searches for neutral heavy leptons at future facilities. In contrast, testing leptogenesis from out-of-equilibrium decays is a quite difficult task. We comment on the necessary conditions for having successful leptogenesis at the TeV-scale. We further discuss possible realizations and their model specific testability in extended seesaw models, models with extended gauge sectors, and supersymmetric leptogenesis. Not being able to test high-scale leptogenesis directly, we present a way to falsify such scenarios by focusing on their washout processes. This is discussed specifically for the left-right symmetric model and the observation of a heavy W-R, as well as model independently when measuring Delta L = 2 washout processes at the LHC or neutrinoless double beta decay.
Address [Chun, E. J.] Korea Inst Adv Study, Seoul 02455, South Korea, Email: jharz@lpthe.jussieu.fr
Corporate Author Thesis
Publisher World Scientific Publ Co Pte Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0217-751x ISBN Medium
Area Expedition Conference
Notes WOS:000426586100006 Approved no
Is ISI yes International Collaboration (down) yes
Call Number IFIC @ pastor @ Serial 3507
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