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Author Bernabeu, J.; Segarra, A.
Title Stimulated transitions in resonant atom Majorana mixing Type Journal Article
Year 2018 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 02 Issue (up) 2 Pages 017 - 16pp
Keywords Neutrino Physics; Beyond Standard Model; Global Symmetries
Abstract Massive neutrinos demand to ask whether they are Dirac or Majorana particles. Majorana neutrinos are an irrefutable proof of physics beyond the Standard Model. Neutrinoless double electron capture is not a process but a virtual Delta L = 2 mixing between a parent (A)Z atom and a daughter (A)(Z – 2) excited atom with two electron holes. As a mixing between two neutral atoms and the observable signal in terms of emitted two-hole X-rays, the strategy, experimental signature and background are different from neutrinoless double beta decay. The mixing is resonantly enhanced for almost degeneracy and, under these conditions, there is no irreducible background from the standard two-neutrino channel. We reconstruct the natural time history of a nominally stable parent atom since its production either by nature or in the laboratory. After the time periods of atom oscillations and the decay of the short-lived daughter atom, at observable times the relevant 'stationary" states are the mixed metastable long-lived state and the non-orthogonal short-lived excited state, as well as the ground state of the daughter atom. We find that they have a natural population inversion which is most appropriate for exploiting the bosonic nature of the observed atomic transitions radiation. Among different observables of the atom Majorana mixing, we include the enhanced rate of stimulated X-ray emission from the long-lived metastable state by a high-intensity X-ray beam: a gain factor of 100 can be envisaged at current XFEL facilities. On the other hand, the historical population of the daughter atom ground state can be probed by exciting it with a current pulsed optical laser, showing the characteristic absorption lines: the whole population can be excited in a shorter time than typical pulse duration.
Address [Bernabeu, Jose] Univ Valencia, CSIC, Dept Fis Teor, Calle Dr Moliner 50, E-46100 Burjassot, Spain, Email: Jose.Bernabeu@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:000424101600008 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 3475
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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 (up) 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 WOS:000426478100001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3511
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Author Carcamo Hernandez, A.E.; Kovalenko, S.; Valle, J.W.F.; Vaquera-Araujo, C.A.
Title Neutrino predictions from a left-right symmetric flavored extension of the standard model Type Journal Article
Year 2019 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 02 Issue (up) 2 Pages 065 - 24pp
Keywords Beyond Standard Model; Discrete Symmetries; Neutrino Physics; Quark Masses and SM Parameters
Abstract We propose a left-right symmetric electroweak extension of the Standard Model based on the Delta (27) family symmetry. The masses of all electrically charged Standard Model fermions lighter than the top quark are induced by a Universal Seesaw mechanism mediated by exotic fermions. The top quark is the only Standard Model fermion to get mass directly from a tree level renormalizable Yukawa interaction, while neutrinos are unique in that they get calculable radiative masses through a low-scale seesaw mechanism. The scheme has generalized μ- tau symmetry and leads to a restricted range of neutrino oscillations parameters, with a nonzero neutrinoless double beta decay amplitude lying at the upper ranges generically associated to normal and inverted neutrino mass ordering.
Address [Carcamo Hernandez, A. E.; Kovalenko, Sergey] Univ Tecn Federico Santa Maria, Casilla 110-5, Valparaiso, Chile, Email: antonio.carcamo@usm.cl;
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:000459168900003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3917
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Author Baxter, D.; Collar, J.I.; Coloma, P.; Dahl, C.E.; Esteban, I.; Ferrario, P.; Gomez-Cadenas, J.J.; Gonzalez-Garcia, M.C.; Kavner, A.R.L.; Lewis, C.M.; Monrabal, F.; Vidal, J.M.; Privitera, P.; Ramanathan, K.; Renner, J.
Title Coherent elastic neutrino-nucleus scattering at the European Spallation Source Type Journal Article
Year 2020 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 02 Issue (up) 2 Pages 123 - 38pp
Keywords Neutrino Detectors and Telescopes (experiments); Beyond Standard Model; Electroweak interaction
Abstract The European Spallation Source (ESS), presently well on its way to completion, will soon provide the most intense neutron beams for multi-disciplinary science. Fortuitously, it will also generate the largest pulsed neutrino flux suitable for the detection of Coherent Elastic Neutrino-Nucleus Scattering (CE nu NS), a process recently measured for the first time at ORNL's Spallation Neutron Source. We describe innovative detector technologies maximally able to profit from the order-of-magnitude increase in neutrino flux provided by the ESS, along with their sensitivity to a rich particle physics phenomenology accessible through high-statistics, precision CE nu NS measurements.
Address [Baxter, D.; Collar, J. I.; Kavner, A. R. L.; Lewis, C. M.; Privitera, P.; Ramanathan, K.] Univ Chicago, Enrico Fermi Inst, Kavli Inst Cosmol Phys, 5640 S Ellis Ave, Chicago, IL 60637 USA, Email: collar@uchicago.edu;
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:000515509000001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4300
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Author Arguelles, C.A.; Coloma, P.; Hernandez, P.; Muñoz, V.
Title Searches for atmospheric long-lived particles Type Journal Article
Year 2020 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 02 Issue (up) 2 Pages 190 - 34pp
Keywords Beyond Standard Model; Neutrino Physics; Solar and Atmospheric Neutrinos
Abstract Long-lived particles are predicted in extensions of the Standard Model that involve relatively light but very weakly interacting sectors. In this paper we consider the possibility that some of these particles are produced in atmospheric cosmic ray showers, and their decay intercepted by neutrino detectors such as IceCube or Super-Kamiokande. We present the methodology and evaluate the sensitivity of these searches in various scenarios, including extensions with heavy neutral leptons in models of massive neutrinos, models with an extra U(1) gauge symmetry, and a combination of both in a U(1)(B-L) model. Our results are shown as a function of the production rate and the lifetime of the corresponding long-lived particles.
Address [Arguelles, C.] MIT, Dept Phys, Cambridge, MA 02139 USA, Email: caad@mit.edu;
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:000518622800001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4323
Permanent link to this record