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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
Permanent link to this record
 
 
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
Permanent link to this record
 
 
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
 
 
Author Coloma, P.; Esteban, I.; Gonzalez-Garcia, M.C.; Maltoni, M.
Title Improved global fit to Non-Standard neutrino Interactions using COHERENT energy and timing data Type Journal Article
Year 2020 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 02 Issue (up) 2 Pages 023 - 30pp
Keywords Beyond Standard Model; Neutrino Physics; Solar and Atmospheric Neutrinos
Abstract We perform a global fit to neutrino oscillation and coherent neutrino-nucleus scattering data, using both timing and energy information from the COHERENT experiment. The results are used to set model-independent bounds on four-fermion effective operators inducing non-standard neutral-current neutrino interactions. We quantify the allowed ranges for their Wilson coefficients, as well as the status of the LMA-D solution, for a wide class of new physics models with arbitrary ratios between the strength of the operators involving up and down quarks. Our results are presented for the COHERENT experiment alone, as well as in combination with the global data from oscillation experiments. We also quantify the dependence of our results for COHERENT with respect to the choice of quenching factor, nuclear form factor, and the treatment of the backgrounds.
Address [Coloma, Pilar] Univ Valencia, Inst Fis Corpuscular, Edificio Inst Invest, E-46980 Valencia, Spain, Email: pcoloma@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:000519223000001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4330
Permanent link to this record
 
 
Author de Salas, P.F.; Forero, D.V.; Gariazzo, S.; Martinez-Mirave, P.; Mena, O.; Ternes, C.A.; Tortola, M.; Valle, J.W.F.
Title 2020 global reassessment of the neutrino oscillation picture Type Journal Article
Year 2021 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 02 Issue (up) 2 Pages 071 - 36pp
Keywords Beyond Standard Model; Neutrino Physics
Abstract We present an updated global fit of neutrino oscillation data in the simplest three-neutrino framework. In the present study we include up-to-date analyses from a number of experiments. Concerning the atmospheric and solar sectors, besides the data considered previously, we give updated analyses of IceCube DeepCore and Sudbury Neutrino Observatory data, respectively. We have also included the latest electron antineutrino data collected by the Daya Bay and RENO reactor experiments, and the long-baseline T2K and NO nu A measurements, as reported in the Neutrino 2020 conference. All in all, these new analyses result in more accurate measurements of theta (13), theta (12), Delta m212 and Delta m312. The best fit value for the atmospheric angle theta (23) lies in the second octant, but first octant solutions remain allowed at similar to 2.4 sigma. Regarding CP violation measurements, the preferred value of delta we obtain is 1.08 pi (1.58 pi) for normal (inverted) neutrino mass ordering. The global analysis still prefers normal neutrino mass ordering with 2.5 sigma statistical significance. This preference is milder than the one found in previous global analyses. These new results should be regarded as robust due to the agreement found between our Bayesian and frequentist approaches. Taking into account only oscillation data, there is a weak/moderate preference for the normal neutrino mass ordering of 2.00 sigma. While adding neutrinoless double beta decay from the latest Gerda, CUORE and KamLAND-Zen results barely modifies this picture, cosmological measurements raise the preference to 2.68 sigma within a conservative approach. A more aggressive data set combination of cosmological observations leads to a similar preference for normal with respect to inverted mass ordering, namely 2.70 sigma. This very same cosmological data set provides 2 sigma upper limits on the total neutrino mass corresponding to Sigma m(nu)< 0.12 (0.15) eV in the normal (inverted) neutrino mass ordering scenario. The bounds on the neutrino mixing parameters and masses presented in this up-to-date global fit analysis include all currently available neutrino physics inputs.
Address [de Salas, P. F.] Stockholm Univ, Oskar Klein Ctr Cosmoparticle Phys, Dept Phys, AlbaNova, S-10691 Stockholm, Sweden, Email: pablo.fernandez@fysik.su.se;
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:000618343000003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4727
Permanent link to this record
 
 
Author Belanger, G.; Bharucha, A.; Fuks, B.; Goudelis, A.; Heisig, J.; Jueid, A.; Lessa, A.; Mohan, K.A.; Polesello, G.; Pani, P.; Pukhov, A.; Sengupta, D.; Zurita, J.
Title Leptoquark manoeuvres in the dark: a simultaneous solution of the dark matter problem and the R-D(*) anomalies Type Journal Article
Year 2022 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 02 Issue (up) 2 Pages 042 - 58pp
Keywords Beyond Standard Model; Heavy Quark Physics; GUT
Abstract The measured branching fractions of B-mesons into leptonic final states derived by the LHCb, Belle and BaBar collaborations hint towards the breakdown of lepton flavour universality. In this work we take at face value the so-called R-D(()*()) observables that are defined as the ratios of neutral B-meson charged-current decays into a D-(*())-meson, a charged lepton and a neutrino final state in the tau and light lepton channels. A well-studied and simple solution to this charged current anomaly is to introduce a scalar leptoquark S-1 that couples to the second and third generation of fermions. We investigate how S-1 can also serve as a mediator between the Standard Model and a dark sector. We study this scenario in detail and estimate the constraints arising from collider searches for leptoquarks, collider searches for missing energy signals, direct detection experiments and the dark matter relic abundance. We stress that the production of a pair of leptoquarks that decays into different final states (i.e. the commonly called “mixed” channels) provides critical information for identifying the underlying dynamics, and we exemplify this by studying the t tau b nu and the resonant S-1 plus missing energy channels. We find that direct detection data provides non-negligible constraints on the leptoquark coupling to the dark sector, which in turn affects the relic abundance. We also show that the correct relic abundance can not only arise via standard freeze-out, but also through conversion-driven freeze-out. We illustrate the rich phenomenology of the model with a few selected benchmark points, providing a broad stroke of the interesting connection between lepton flavour universality violation and dark matter.
Address [Belanger, Genevieve] Univ Grenoble Alpes, CNRS, USMB, LAPTh, 9 Chemin Bellevue, F-74940 Annecy, France, Email: belanger@lapth.cnrs.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:000752903000005 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5115
Permanent link to this record
 
 
Author ATLAS Collaboration (Aad, G. et al); Aikot, A.; Amos, K.R.; Aparisi Pozo, J.A.; Bailey, A.J.; Bouchhar, N.; Cabrera Urban, S.; Cantero, J.; Cardillo, F.; Castillo Gimenez, V.; Chitishvili, M.; Costa, M.J.; Didenko, M.; Escobar, C.; Fiorini, L.; Fuster, J.; Garcia, C.; Garcia Navarro, J.E.; Gomez Delegido, A.J.; Gonzalez de la Hoz, S.; Gonzalvo Rodriguez, G.R.; Guerrero Rojas, J.G.R.; Lacasta, C.; Marti-Garcia, S.; Martinez Agullo, P.; Miralles Lopez, M.; Mitsou, V.A.; Monsonis Romero, L.; Moreno Llacer, M.; Munoz Perez, D.; Navarro-Gonzalez, J.; Poveda, J.; Prades Ibañez, A.; Rubio Jimenez, A.; Ruiz-Martinez, A.; Sabatini, P.; Saibel, A.; Salt, J.; Sanchez Sebastian, V.; Sayago Galvan, I.; Senthilkumar, V.; Soldevila, U.; Sanchez, J.; Torro Pastor, E.; Valero, A.; Valiente Moreno, E.; Valls Ferrer, J.A.; Varriale, L.; Villaplana Perez, M.; Vos, M.
Title Search for resonant production of dark quarks in the dijet final state with the ATLAS detector Type Journal Article
Year 2024 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 02 Issue (up) 2 Pages 128 - 35pp
Keywords Beyond Standard Model; Hadron-Hadron Scattering; Dark Matter; Exotics
Abstract This paper presents a search for a new Z' resonance decaying into a pair of dark quarks which hadronise into dark hadrons before promptly decaying back as Standard Model particles. This analysis is based on proton-proton collision data recorded at root s = 13TeV with the ATLAS detector at the Large Hadron Collider between 2015 and 2018, corresponding to an integrated luminosity of 139 fb(-1). After selecting events containing large-radius jets with high track multiplicity, the invariant mass distribution of the two highest-transverse-momentum jets is scanned to look for an excess above a data-driven estimate of the Standard Model multijet background. No significant excess of events is observed and the results are thus used to set 95% confidence-level upper limits on the production cross-section times branching ratio of the Z' to dark quarks as a function of the Z' mass for various dark-quark scenarios.
Address [Filmer, E. K.; Grant, C. M.; Jackson, P.; Kong, A. X. Y.; Pandya, H. D.; Potti, H.; Ruggeri, T. A.; Ting, E. X. L.; White, M. J.] Univ Adelaide, Dept Phys, Adelaide, SA, Australia
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:001185478500001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6046
Permanent link to this record
 
 
Author ATLAS Collaboration (Aad, G. et al); Amos, K.R.; Aparisi Pozo, J.A.; Bailey, A.J.; Bouchhar, N.; Cabrera Urban, S.; Cantero, J.; Cardillo, F.; Castillo Gimenez, V.; Chitishvili, M.; Costa, M.J.; Didenko, M.; Escobar, C.; Fiorini, L.; Fullana Torregrosa, E.; Fuster, J.; Garcia, C.; Garcia Navarro, J.E.; Gomez Delegido, A.J.; Gonzalez de la Hoz, S.; Gonzalvo Rodriguez, G.R.; Guerrero Rojas, J.G.R.; Lacasta, C.; Marti-Garcia, S.; Martinez Agullo, P.; Miralles Lopez, M.; Mitsou, V.A.; Monsonis Romero, L.; Moreno Llacer, M.; Munoz Perez, D.; Navarro-Gonzalez, J.; Poveda, J.; Prades Ibañez, A.; Rubio Jimenez, A.; Ruiz-Martinez, A.; Sabatini, P.; Salt, J.; Sanchez Sebastian, V.; Sayago Galvan, I.; Senthilkumar, V.; Soldevila, U.; Sanchez, J.; Torro Pastor, E.; Valero, A.; Valiente Moreno, E.; Valls Ferrer, J.A.; Varriale, L.; Villaplana Perez, M.; Vos, M.
Title Search for pair production of squarks or gluinos decaying via sleptons or weak bosons in final states with two same-sign or three leptons with the ATLAS detector Type Journal Article
Year 2024 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 02 Issue (up) 2 Pages 107 - 55pp
Keywords Beyond Standard Model; Hadron-Hadron Scattering; Lepton Production; Supersymmetry
Abstract A search for pair production of squarks or gluinos decaying via sleptons or weak bosons is reported. The search targets a final state with exactly two leptons with same-sign electric charge or at least three leptons without any charge requirement. The analysed data set corresponds to an integrated luminosity of 139 fb(-1) of proton-proton collisions collected at a centre-of-mass energy of 13TeV with the ATLAS detector at the LHC. Multiple signal regions are defined, targeting several SUSY simplified models yielding the desired final states. A single control region is used to constrain the normalisation of the WZ + jets background. No significant excess of events over the Standard Model expectation is observed. The results are interpreted in the context of several supersymmetric models featuring R-parity conservation or R-parity violation, yielding exclusion limits surpassing those from previous searches. In models considering gluino (squark) pair production, gluino (squark) masses up to 2.2 (1.7) TeV are excluded at 95% confidence level.
Address [Filmer, E. K.; Jackson, P.; Kong, A. X. Y.; Potti, H.; Ruggeri, T. A.; Ting, E. X. L.; White, M. J.] Univ Adelaide, Dept Phys, Adelaide, SA, Australia
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:001185394700002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6154
Permanent link to this record