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Author Cerdeño, D.G.; De Romeri, V.; Martin Lozano, V.; Olive, K.A.; Seto, O.
Title The Constrained NMSSM with right-handed neutrinos Type Journal Article
Year 2018 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 78 Issue 4 Pages 290 - 12pp
Keywords
Abstract In this article, we demonstrate that the inclusion of right-handed neutrino superfields in the Next-to-Minimal Supersymmetric Standard Model (NMSSM) makes it possible to impose universality conditions on the soft supersymmetry-breaking parameters at the Grand Unification scale, alleviating many of the problems of the so-called Constrained NMSSM. We have studied the renormalization group equations of this model, showing that right-handed neutrinos greatly contribute to driving the singlet Higgs mass-squared parameter negative, which makes it considerably easier to satisfy the conditions for radiative electroweak symmetry breaking. The new fields also lead to larger values of the Standard Model Higgs mass, thus making it easier to reproduce the measured value. As a consequence, all bounds from colliders and low-energy observables can be fulfilled in wide areas of the parameter space. However, the relic density in these regions is generally too high requiring some form of late entropy production to dilute the density of the lightest supersymmetric particle.
Address [Cerdeno, David G.] Univ Durham, Inst Particle Phys Phenomenol, Dept Phys, Durham DH1 3LE, England, Email: lozano@physik.uni-bonn.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 1434-6044 ISBN Medium
Area Expedition Conference
Notes (down) WOS:000429589900004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3558
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Author Abada, A.; De Romeri, V.; Lucente, M.; Teixeira, A.M.; Toma, T.
Title Effective Majorana mass matrix from tau and pseudoscalar meson lepton number violating decays Type Journal Article
Year 2018 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 02 Issue 2 Pages 169 - 57pp
Keywords Beyond Standard Model; Neutrino Physics
Abstract An observation of any lepton number violating process will undoubtedly point towards the existence of new physics and indirectly to the clear Majorana nature of the exchanged fermion. In this work, we explore the potential of a minimal extension of the Standard Model via heavy sterile fermions with masses in the [0.1-10] GeV range concerning an extensive array of “neutrinoless” meson and tau decay processes. We assume that the Majorana neutrinos are produced on-shell, and focus on three-body decays. We conduct an update on the bounds on the active-sterile mixing elements, vertical bar U-l alpha 4,U-l beta 4 vertical bar, taking into account the most recent experimental bounds (and constraints) and new theoretical inputs, as well as the effects of a finite detector, imposing that the heavy neutrino decay within the detector. This allows to establish up-to-date comprehensive constraints on the sterile fermion parameter space. Our results suggest that the branching fractions of several decays are close to current sensitivities (likely within reach of future facilities), some being already in conflict with current data (as is the case of K-broken vertical bar -> l(alpha)(broken vertical bar)+l(beta)(+)pi(-), and tau(-)->mu(broken vertical bar)pi(-)pi(-)). We use these processes to extract constraints on all entries of an enlarged definition of a 3 x 3 “effective” Majorana neutrino mass matrix m(v)(alpha beta).
Address [Abada, Asmaa] Univ Paris Saclay, Univ Paris Sud, CNRS, Lab Phys Theor, 15 Rue Georges Clemenceau, F-91405 Orsay, France, Email: abada@th.u-psud.fr;
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 (down) WOS:000426478100001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3511
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Author De Romeri, V.; Fernandez-Martinez, E.; Gehrlein, J.; Machado, P.A.N.; Niro, V.
Title Dark Matter and the elusive Z' in a dynamical Inverse Seesaw scenario Type Journal Article
Year 2017 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 10 Issue 10 Pages 169 - 21pp
Keywords Beyond Standard Model; Neutrino Physics
Abstract The Inverse Seesaw naturally explains the smallness of neutrino masses via an approximate B-L symmetry broken only by a correspondingly small parameter. In this work the possible dynamical generation of the Inverse Seesaw neutrino mass mechanism from the spontaneous breaking of a gauged U(1) B-L symmetry is investigated. Interestingly, the Inverse Seesaw pattern requires a chiral content such that anomaly cancellation predicts the existence of extra fermions belonging to a dark sector with large, non-trivial, charges under the U(1) B-L. We investigate the phenomenology associated to these new states and find that one of them is a viable dark matter candidate with mass around the TeV scale, whose interaction with the Standard Model is mediated by the Z' boson associated to the gauged U(1) B-L symmetry. Given the large charges required for anomaly cancellation in the dark sector, the B-L Z' interacts preferentially with this dark sector rather than with the Standard Model. This suppresses the rate at direct detection searches and thus alleviates the constraints on Z'-mediated dark matter relic abundance. The collider phenomenology of this elusive Z' is also discussed.
Address [De Romeri, Valentina] Univ Valencia, CSIC, Inst Fis Corpuscular, AHEP Grp, Calle Catedrat Jose Beltran 2, E-46980 Paterna, Spain, Email: deromeri@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 (down) WOS:000414811300001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3357
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Author De Romeri, V.; Kim, J.S.; Martin Lozano, V.; Rolbiecki, K.; Ruiz de Austri, R.
Title Confronting dark matter with the diphoton excess from a parent resonance decay Type Journal Article
Year 2016 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 76 Issue 5 Pages 262 - 13pp
Keywords
Abstract A diphoton excess with an invariant mass of about 750 GeV has been recently reported by both ATLAS and CMS experiments at LHC. While the simplest interpretation requires the resonant production of a 750 GeV (pseudo) scalar, here we consider an alternative setup, with an additional heavy parent particle which decays into a pair of 750 GeV resonances. This configuration improves the agreement between the 8 and 13 TeV data. Moreover, we include a dark matter candidate in the form of a Majorana fermion which interacts through the 750 GeV portal. The invisible decays of the light resonance help to suppress additional decay channels into Standard Model particles in association with the diphoton signal. We realise our hierarchical framework in the context of an effective theory, and we analyse the diphoton signal as well as the consistency with other LHC searches. We finally address the interplay of the LHC results with the dark matter phenomenology, namely the compatibility with the relic density abundance and the indirect detection bounds.
Address [De Romeri, Valentina; Kim, Jong Soo; Martin-Lozano, Victor; Rolbiecki, Krzysztof] Univ Autonoma Madrid, Inst Fis Teor UAM CSIC, E-28049 Madrid, Spain, Email: valentina.deromeri@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 1434-6044 ISBN Medium
Area Expedition Conference
Notes (down) WOS:000399931700001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3088
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Author De Romeri, V.; Fernandez-Martinez, E.; Sorel, M.
Title Neutrino oscillations at DUNE with improved energy reconstruction Type Journal Article
Year 2016 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 09 Issue 9 Pages 030 - 25pp
Keywords CP violation; Neutrino Physics
Abstract We study the physics reach of the long-baseline oscillation analysis of the DUNE experiment when realistic simulations are used to estimate its neutrino energy reconstruction capabilities. Our studies indicate that significant improvements in energy resolution compared to what is customarily assumed are plausible. This improved energy resolution can increase the sensitivity to leptonic CP violation in two ways. On the one hand, the CP-violating term in the oscillation probability has a characteristic energy dependence that can be better reproduced. On the other hand, the second oscillation maximum, especially sensitive to delta(CP), is better reconstructed. These effects lead to a significant improvement in the fraction of values of delta(CP) for which a 5 sigma discovery of leptonic CP-violation would be possible. The precision of the delta(CP) measurement could also be greatly enhanced, with a reduction of the maximum uncertainties from 26 degrees to 18 degrees for a 300 MW.kt.yr exposure. We therefore believe that this potential gain in physics reach merits further investigations of the detector performance achievable in DUNE.
Address [De Romeri, Valentina; Fernandez-Martinez, Enrique] Univ Autonoma Madrid, Dept Fis Teor, E-28049 Madrid, Spain, Email: valentina.deromeri@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 1029-8479 ISBN Medium
Area Expedition Conference
Notes (down) WOS:000382887300001 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 2807
Permanent link to this record