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Author Centelles Chulia, S.; Cepedello, R.; Peinado, E.; Srivastava, R.
Title Scotogenic dark symmetry as a residual subgroup of Standard Model symmetries Type Journal Article
Year 2020 Publication Chinese Physics C Abbreviated Journal Chin. Phys. C
Volume 44 Issue 8 Pages 083110 - 7pp
Keywords neutrino masses; dark matter; symmetries; scotogenic
Abstract We demonstrate that a scotogenic dark symmetry can be obtained as a residual subgroup of the global U(1)(B-L) symmetry already present in the Standard Model. In addition, we propose a general framework in which the U(1)(B-L) symmetry is spontaneously broken into an even Z(2n) subgroup, setting the general conditions for neutrinos to be Majorana and for dark matter stability to exist in terms of the residual Z(2n). As an example, under this general framework, we build a class of simple models where, in a scotogenic manner, the dark matter candidate is the lightest particle running inside the mass loop of a neutrino. The global U(1)(B-L) symmetry in our framework, being anomaly free, can also be gauged in a straightforward manner leading to a richer phenomenology.
Address [Chulia, Salvador Centelles; Cepedello, Ricardo; Srivastava, Rahul] Univ Valencia, CSIC, Inst Fis Corpuscular, AHEP Grp, Parc Cient Paterna C Catedratico Jose Beltran 2, E-46980 Paterna, Valencia, Spain, Email: salcen@ific.uv.es;
Corporate Author Thesis
Publisher (up) 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 1674-1137 ISBN Medium
Area Expedition Conference
Notes WOS:000557423400001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4494
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Author Bernabeu, J.
Title Symmetries and Their Breaking in the Fundamental Laws of Physics Type Journal Article
Year 2020 Publication Symmetry-Basel Abbreviated Journal Symmetry-Basel
Volume 12 Issue 8 Pages 1316 - 27pp
Keywords flavour families; colour charges; gauge symmetries; chirality; discrete symmetries; neutrinos; spontaneous breaking
Abstract Symmetries in the Physical Laws of Nature lead to observable effects. Beyond the regularities and conserved magnitudes, the last few decades in particle physics have seen the identification of symmetries, and their well-defined breaking, as the guiding principle for the elementary constituents of matter and their interactions. Flavour SU(3) symmetry of hadrons led to the Quark Model and the antisymmetric requirement under exchange of identical fermions led to the colour degree of freedom. Colour became the generating charge for flavour-independent strong interactions of quarks and gluons in the exact colour SU(3) local gauge symmetry. Parity Violation in weak interactions led us to consider the chiral fields of fermions as the objects with definite transformation properties under the weak isospin SU(2) gauge group of the Unifying Electro-Weak SU(2) x U(1) symmetry, which predicted novel weak neutral current interactions. CP-Violation led to three families of quarks opening the field of Flavour Physics. Time-reversal violation has recently been observed with entangled neutral mesons, compatible with CPT-invariance. The cancellation of gauge anomalies, which would invalidate the gauge symmetry of the quantum field theory, led to Quark-Lepton Symmetry. Neutrinos were postulated in order to save the conservation laws of energy and angular momentum in nuclear beta decay. After the ups and downs of their mass, neutrino oscillations were discovered in 1998, opening a new era about their origin of mass, mixing, discrete symmetries and the possibility of global lepton-number violation through Majorana mass terms and Leptogenesis as the source of the matter-antimatter asymmetry in the universe. The experimental discovery of quarks and leptons and the mediators of their interactions, with physical observables in spectacular agreement with this Standard Theory, is the triumph of Symmetries. The gauge symmetry is exact only when the particles are massless. One needs a subtle breaking of the symmetry, providing the origin of mass without affecting the excellent description of the interactions. This is the Brout-Englert-Higgs Mechanism, which produces the Higgs Boson as a remnant, discovered at CERN in 2012. Open present problems are addressed with by searching the New Physics Beyond-the-Standard-Model.
Address [Bernabeu, Jose] Univ Valencia, Dept Theoret Phys, E-46100 Burjassot, Spain, Email: Jose.Bernabeu@uv.es
Corporate Author Thesis
Publisher (up) Mdpi Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes WOS:000564717500001 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 4523
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Author Rodriguez-Alvarez, M.J.; Sanchez, F.; Soriano, A.; Iborra, A.; Mora, C.
Title Exploiting symmetries for weight matrix design in CT imaging Type Journal Article
Year 2011 Publication Mathematical and Computer Modelling Abbreviated Journal Math. Comput. Model.
Volume 54 Issue 7-8 Pages 1655-1664
Keywords Computerized tomography imaging; Polar grid; System matrix; Rotation symmetries; ART
Abstract In this paper we propose several methods of constructing the system matrix (SM) of a Computed Tomography (CT) scanner with two objectives: (1) to construct SMs in the shortest possible time and store them in an ordinary PC without losing quality, (2) to analyze the possible applications of the proposed method to 3D, taking into account SMs' sizes, computing time and reconstructed image quality. In order to build the SM, we propose two new field of view (FOV) pixellation schemes, based on a polar coordinate system (polar grid) by taking advantage of the polar rotation symmetries of CT devices. Comparisons between the SMs proposed are performed using two phantom and a real CT-simulator images. Global error, contrast, noise and homogeneity of the reconstructed images are discussed.
Address [Rodriguez-Alvarez, MJ; Iborra, A; Mora, C] Univ Politecn Valencia, Inst Matemat Multidisciplinar, Valencia 46022, Spain, Email: mjrodri@imm.upv.es
Corporate Author Thesis
Publisher (up) Pergamon-Elsevier Science Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0895-7177 ISBN Medium
Area Expedition Conference
Notes WOS:000293269200007 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ elepoucu @ Serial 708
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Author Bustamante, M.; Gago, A.M.; Pena-Garay, C.
Title Energy-independent new physics in the flavour ratios of high-energy astrophysical neutrinos Type Journal Article
Year 2010 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 04 Issue 4 Pages 066 - 28pp
Keywords Beyond Standard Model; Neutrino Physics; Discrete and Finite Symmetries
Abstract We have studied the consequences of breaking the CPT symmetry in the neutrino sector, using the expected high-energy neutrino flux from distant cosmological sources such as active galaxies. For this purpose we have assumed three different hypotheses for the neutrino production model, characterised by the flavour fluxes at production phi(0)(e) : phi(0)(mu) : phi(0)(tau) = 1 : 2 : 0, 0 : 1 : 0, and 1 : 0 : 0, and studied the theoretical and experimental expectations for the muon-neutrino flux at Earth, phi(mu), and for the flavour ratios at Earth, R = phi(mu)/phi(e) and S = phi(tau)/phi(mu). CPT violation (CPTV) has been implemented by adding an energy-independent term to the standard neutrino oscillation Hamiltonian. This introduces three new mixing angles, two new eigenvalues and three new phases, all of which have currently unknown values. We have varied the new mixing angles and eigenvalues within certain bounds, together with the parameters associated to pure standard oscillations. Our results indicate that, for the models 1 : 2 : 0 and 0 : 1 : 0, it might be possible to find large deviations of phi(mu), R, and S between the cases without and with CPTV, provided the CPTV eigenvalues lie within 10(-29) – 10(-27) GeV, or above. Moreover, if CPTV exists, there are certain values of R and S that can be accounted for by up to three production models. If no CPTV were observed, we could set limits on the CPTV eigenvalues of the same order. Detection prospects calculated using IceCube suggest that for the models 1 : 2 : 0 and 0 : 1 : 0, the modifications due to CPTV are larger and more clearly separable from the standard-oscillations predictions. We conclude that IceCube is potentially able to detect CPTV but that, depending on the values of the CPTV parameters, there could be a mis-determination of the neutrino production model.
Address [Bustamante, M.; Gago, A. M.] Univ Catolica Peru, Secc Fis, Dept Ciencias, Lima, Peru, Email: mbustamante@pucp.edu.pe
Corporate Author Thesis
Publisher (up) 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 ISI:000277473100004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 455
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Author Boucenna, M.S.; Hirsch, M.; Morisi, S.; Peinado, E.; Taoso, M.; Valle, J.W.F.
Title Phenomenology of dark matter from A_4 flavor symmetry Type Journal Article
Year 2011 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 05 Issue 5 Pages 037 - 20pp
Keywords Cosmology of Theories beyond the SM; Neutrino Physics; Discrete and Finite Symmetries
Abstract We investigate a model in which Dark Matter is stabilized by means of a Z(2) parity that results from the same non-abelian discrete flavor symmetry which accounts for the observed patter of neutrino mixing. In our A(4) example the standard model is extended by three extra Higgs doublets and the Z(2) parity emerges as a remnant of the spontaneous breaking of A(4) after electroweak symmetry breaking. We perform an analysis of the parameter space of the model consistent with electroweak precision tests, collider searches and perturbativity. We determine the regions compatible with the observed relic dark matter density and we present prospects for detection in direct as well as indirect Dark Matter search experiments.
Address [Boucenna, M. S.; Hirsch, M.; Morisi, S.; Peinado, E.; Taoso, M.; Valle, J. W. F.] Univ Valencia, CSIC, Inst Fis Corpuscular, AHEP Grp, E-46071 Valencia, Spain, Email: boucenna@ific.uv.es
Corporate Author Thesis
Publisher (up) 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 ISI:000291364300037 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ elepoucu @ Serial 674
Permanent link to this record