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Author Abada, A.; De Romeri, V.; Lucente, M.; Teixeira, A.M.; Toma, T.
Title (up) 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 WOS:000426478100001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3511
Permanent link to this record
 
 
Author Fernandez-Martinez, E.; Gonzalez-Lopez, M.; Hernandez-Garcia, J.; Hostert, M.; Lopez-Pavon, J.
Title (up) Effective portals to heavy neutral leptons Type Journal Article
Year 2023 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 09 Issue 9 Pages 001 - 45pp
Keywords Neutrino Interactions; Non-Standard Neutrino Properties; Sterile or Heavy Neutrinos
Abstract The existence of right-handed neutrinos, or heavy neutral leptons (HNLs), is strongly motivated by the observation of neutrino masses and mixing. The mass of these new particles could lie below the electroweak scale, making them accessible to lowenergy laboratory experiments. Additional new physics at high energies can mediate new interactions between the Standard Model particles and HNLs, and is most conveniently parametrized by the neutrino Standard Model Effective Field Theory, or nu SMEFT for short. In this work, we consider the dimension six nu SMEFT operators involving one HNL field in the mass range of O(1) MeV < MN < O(100) GeV. By recasting existing experimental limits on the production and decay of new light particles, we constrain the Wilson coefficients and new physics scale of each operator as a function of the HNL mass.
Address [Fernandez-Martinez, Enrique; Gonzalez-Lopez, Manuel] Univ Autonoma Madrid, Inst Fis Teor, Campus Cantoblanco, Madrid 28049, Spain, Email: enrique.fernandez-martinez@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 WOS:001067715500003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5697
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Author Foffa, S.; Sturani, R.; Torres Bobadilla, W.J.
Title (up) Efficient resummation of high post-Newtonian contributions to the binding energy Type Journal Article
Year 2021 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 02 Issue 2 Pages 165 - 18pp
Keywords Classical Theories of Gravity; Black Holes; Effective Field Theories
Abstract A factorisation property of Feynman diagrams in the context the Effective Field Theory approach to the compact binary problem has been recently employed to efficiently determine the static sector of the potential at fifth post-Newtonian (5PN) order. We extend this procedure to the case of non-static diagrams and we use it to fix, by means of elementary algebraic manipulations, the value of more than one thousand diagrams at 5PN order, that is a substantial fraction of the diagrams needed to fully determine the dynamics at 5PN. This procedure addresses the redundancy problem that plagues the computation of the binding energy with respect to more “efficient” observables like the scattering angle, thus making the EFT approach in harmonic gauge at least as scalable as the others methods.
Address [Foffa, Stefano] Univ Geneva, Dept Phys Theor, CH-1211 Geneva, Switzerland, Email: stefano.foffa@unige.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:000621231300003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4740
Permanent link to this record
 
 
Author Breso-Pla, V.; Falkowski, A.; Gonzalez-Alonso, M.; Monsalvez-Pozo, K.
Title (up) EFT analysis of New Physics at COHERENT Type Journal Article
Year 2023 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 05 Issue 5 Pages 074 - 53pp
Keywords Non-Standard Neutrino Properties; Specific BSM Phenomenology; Neutrino Interactions; SMEFT
Abstract Using an effective field theory approach, we study coherent neutrino scattering on nuclei, in the setup pertinent to the COHERENT experiment. We include non-standard effects both in neutrino production and detection, with an arbitrary flavor structure, with all leading Wilson coefficients simultaneously present, and without assuming factorization in flux times cross section. A concise description of the COHERENT event rate is obtained by introducing three generalized weak charges, which can be associated (in a certain sense) to the production and scattering of nu(e), nu(mu) and (nu) over bar (mu) on the nuclear target. Our results are presented in a convenient form that can be trivially applied to specific New Physics scenarios. In particular, we find that existing COHERENT measurements provide percent level constraints on two combinations of Wilson coefficients. These constraints have a visible impact on the global SMEFT fit, even in the constrained flavor-blind setup. The improvement, which affects certain 4-fermion LLQQ operators, is significantly more important in a flavor-general SMEFT. Our work shows that COHERENT data should be included in electroweak precision studies from now on.
Address [Breso-Pla, Victor; Gonzalez-Alonso, Martin; Monsalvez-Pozo, Kevin] Univ Valencia, Dept Fis Teor, IFIC, CSIC, Apt Correus 22085, E-46071 Valencia, Spain, Email: vicbreso@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:000988320800002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5549
Permanent link to this record
 
 
Author Falkowski, A.; Gonzalez-Alonso, M.; Kopp, J.; Soreq, Y.; Tabrizi, Z.
Title (up) EFT at FASER nu Type Journal Article
Year 2021 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 10 Issue 10 Pages 086 - 46pp
Keywords Effective Field Theories; Neutrino Physics
Abstract We investigate the sensitivity of the FASER nu detector to new physics in the form of non-standard neutrino interactions. FASER nu, which will be installed 480 m downstream of the ATLAS interaction point, will for the first time study interactions of multi-TeV neutrinos from a controlled source. Our formalism – which is applicable to any current and future neutrino experiment – is based on the Standard Model Effective Theory (SMEFT) and its counterpart, Weak Effective Field Theory (WEFT), below the electroweak scale. Starting from the WEFT Lagrangian, we compute the coefficients that modify neutrino production in meson decays and detection via deep-inelastic scattering, and we express the new physics effects in terms of modified flavor transition probabilities. For some coupling structures, we find that FASER nu will be able to constrain interactions that are two to three orders of magnitude weaker than Standard Model weak interactions, implying that the experiment will be indirectly probing new physics at the multi-TeV scale. In some cases, FASER nu constraints will become comparable to existing limits – some of them derived for the first time in this paper – already with 150 fb(-1) of data.
Address [Falkowski, Adam] Univ Paris Saclay, CNRS, IN2P3, IJCLab, F-91405 Orsay, France, Email: afalkows017@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:000707348700002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5002
Permanent link to this record
 
 
Author Gisbert, H.; Miralles, V.; Ruiz Vidal, J.
Title (up) Electric dipole moments from colour-octet scalars Type Journal Article
Year 2022 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 04 Issue 4 Pages 077 - 25pp
Keywords Beyond Standard Model; CP violation
Abstract We present the contributions to electric dipole moments (EDMs) induced by the Yukawa couplings of an additional electroweak doublet of colour-octet scalars. The full set of one-loop diagrams and the enhanced higher-order effects from Barr-Zee diagrams are computed for the quark (chromo-)EDM, along with the two-loop contributions to the Weinberg operator. Using the stringent experimental upper limits on the neutron EDM, constraints on the parameter space of the Manohar-Wise model are derived.
Address [Gisbert, Hector] TU Dortmund, Fak Phys, Otto Hahn Str 4, D-44221 Dortmund, Germany, Email: hector.gisbert@tu-dortmund.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:000782602900005 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5198
Permanent link to this record
 
 
Author Jung, M.; Pich, A.
Title (up) Electric dipole moments in two-Higgs-doublet models Type Journal Article
Year 2014 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 04 Issue 4 Pages 076 - 42pp
Keywords Higgs Physics; Beyond Standard Model; CP violation
Abstract Electric dipole moments are extremely sensitive probes for additional sources of CP violation in new physics models. Specifically, they have been argued in the past to exclude new CP-violating phases in two-Higgs-doublet models. Since recently models including such phases have been discussed widely, we revisit the available constraints in the presence of mechanisms which are typically invoked to evade flavour-changing neutral currents. To that aim, we start by assessing the necessary calculations on the hadronic, nuclear and atomic/molecular level, deriving expressions with conservative error estimates. Their phenomenological analysis in the context of two-Higgs-doublet models yields strong constraints, in some cases weakened by a cancellation mechanism among contributions from neutral scalars. While the corresponding parameter combinations do not yet have to be unnaturally small, the constraints are likely to preclude large effects in other CP-violating observables. Nevertheless, the generically expected contributions to electric dipole moments in this class of models lie within the projected sensitivity of the next-generation experiments.
Address [Jung, Martin] Tech Univ Dortmund, Inst Phys, D-44221 Dortmund, Germany, Email: martin2.jung@tu-dortmund.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:000347841200005 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2085
Permanent link to this record
 
 
Author NEXT Collaboration (Henriques, C.A.O. et al); Alvarez, V.; Benlloch-Rodriguez, J.M.; Botas, A.; Carcel, S.; Carrion, J.V.; Diaz, J.; Felkai, R.; Kekic, M.; Laing, A.; Lopez-March, N.; Martinez, A.; Martinez-Lema, G.; Muñoz Vidal, J.; Musti, M.; Nebot-Guinot, M.; Novella, P.; Palmeiro, B.; Perez, J.; Querol, M.; Renner, J.; Rodriguez, J.; Romo-Luque, C.; Simon, A.; Sorel, M.; Yahlali, N.
Title (up) Electroluminescence TPCs at the thermal diffusion limit Type Journal Article
Year 2019 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 01 Issue 1 Pages 027 - 23pp
Keywords Dark Matter and Double Beta Decay (experiments); Photon production; Particle correlations and fluctuations; Rare decay
Abstract The NEXT experiment aims at searching for the hypothetical neutrinoless double-beta decay from the Xe-136 isotope using a high-purity xenon TPC. Efficient discrimination of the events through pattern recognition of the topology of primary ionisation tracks is a major requirement for the experiment. However, it is limited by the diffusion of electrons. It is known that the addition of a small fraction of a molecular gas to xenon reduces electron diffusion. On the other hand, the electroluminescence (EL) yield drops and the achievable energy resolution may be compromised. We have studied the effect of adding several molecular gases to xenon (CO2, CH4 and CF4) on the EL yield and energy resolution obtained in a small prototype of driftless gas proportional scintillation counter. We have compared our results on the scintillation characteristics (EL yield and energy resolution) with a microscopic simulation, obtaining the diffusion coefficients in those conditions as well. Accordingly, electron diffusion may be reduced from about 10 for pure xenon down to 2.5 using additive concentrations of about 0.05%, 0.2% and 0.02% for CO2, CH4 and CF4, respectively. Our results show that CF4 admixtures present the highest EL yield in those conditions, but very poor energy resolution as a result of huge fluctuations observed in the EL formation. CH4 presents the best energy resolution despite the EL yield being the lowest. The results obtained with xenon admixtures are extrapolated to the operational conditions of the NEXT-100 TPC. CO2 and CH4 show potential as molecular additives in a large xenon TPC. While CO2 has some operational constraints, making it difficult to be used in a large TPC, CH4 shows the best performance and stability as molecular additive to be used in the NEXT-100 TPC, with an extrapolated energy resolution of 0.4% at 2.45 MeV for concentrations below 0.4%, which is only slightly worse than the one obtained for pure xenon. We demonstrate the possibility to have an electroluminescence TPC operating very close to the thermal diffusion limit without jeopardizing the TPC performance, if CO2 or CH4 are chosen as additives.
Address [Henriques, C. A. O.; Monteiro, C. M. B.; Freitas, E. D. C.; Mano, R. D. P.; Jorge, M. R.; Fernandes, A. F. M.; Fernandes, L. M. P.; dos Santos, J. M. F.] Univ Coimbra, Phys Dept, LIBPhys, Rua Larga, P-3004516 Coimbra, Portugal, Email: pancho@gian.fis.uc.pt
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:000455157300002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3873
Permanent link to this record
 
 
Author Barenboim, G.; Rasero, J.
Title (up) Electroweak baryogenesis window in non standard cosmologies Type Journal Article
Year 2012 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 07 Issue 7 Pages 028 - 20pp
Keywords Cosmology of Theories beyond the SM; Beyond Standard Model; Neutrino Physics
Abstract In this work we show that the new bounds on the Higgs mass are more than difficult to reconcile with the strong constraints on the physical parameters of the Standard Model and the Minimal Supersymmetric Standard Model imposed by the preservation of the baryon asymmetry. This bound can be weakened by assuming a nonstandard cosmology at the time of the electroweak phase transition, reverting back to standard cosmology by BBN time. Two explicit examples are an early period of matter dominated expansion due to a heavy right handed neutrino (see-saw scale), or a nonstandard braneworld expansion.
Address [Barenboim, Gabriela] Univ Valencia, CSIC, Dept Fis Teor, E-46100 Burjassot, Spain, Email: gabriela.barenboim@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 1126-6708 ISBN Medium
Area Expedition Conference
Notes WOS:000307298400028 Approved no
Is ISI yes International Collaboration
Call Number IFIC @ pastor @ Serial 1158
Permanent link to this record
 
 
Author Fontes, D.; Romao, J.C.; Valle, J.W.F.
Title (up) Electroweak breaking and Higgs boson profile in the simplest linear seesaw model Type Journal Article
Year 2019 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 10 Issue 10 Pages 245 - 28pp
Keywords Beyond Standard Model; Higgs Physics; Neutrino Physics
Abstract We examine the simplest realization of the linear seesaw mechanism within the Standard Model gauge structure. Besides the standard scalar doublet, there are two lepton-number-carrying scalars, a nearly inert SU(2)(L) doublet and a singlet. Neutrino masses result from the spontaneous violation of lepton number, implying the existence of a Nambu-Goldstone boson. Such “majoron” would be copiously produced in stars, leading to stringent astrophysical constraints. We study the profile of the Higgs bosons in this model, including their effective couplings to the vector bosons and their invisible decay branching ratios. A consistent electroweak symmetry breaking pattern emerges with a compressed spectrum of scalars in which the “Standard Model” Higgs boson can have a sizeable invisible decay into the invisible majorons.
Address [Fontes, Duarte; Romao, Jorge C.] Univ Lisbon, Inst Super Tecn, Dept Fis, Ave Rovisco Pais 1, P-1049001 Lisbon, Portugal, Email: duartefontes@tecnico.ulisboa.pt;
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:000495737300001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4199
Permanent link to this record