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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 (down) 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 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 MiniBooNE Collaboration (Aguilar-Arevalo, A.A. et al); Sorel, M.
Title Test of Lorentz and CPT violation with short baseline neutrino oscillation excesses Type Journal Article
Year 2013 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 718 Issue 4-5 Pages (down) 1303-1308
Keywords MiniBooNE; Neutrino oscillation; Lorentz violation
Abstract The sidereal time dependence of MiniBooNE nu(e) and (nu) over bar (e) appearance data is analyzed to search for evidence of Lorentz and CPT violation. An unbinned Kolmogorov-Smirnov (K-S) test shows both the nu(e) and (nu) over bar (e) appearance data are compatible with the null sidereal variation hypothesis to more than 5%. Using an unbinned likelihood fit with a Lorentz-violating oscillation model derived from the Standard Model Extension (SME) to describe any excess events over background, we find that the nu(e) appearance data prefer a sidereal time-independent solution, and the (nu) over bar (e) appearance data slightly prefer a sidereal time-dependent solution. Limits of order 10(-20) GeV are placed on combinations of SME coefficients. These limits give the best limits on certain SME coefficients for nu(mu) -> nu(e) and (nu) over bar (mu) -> (nu) over bar (e) oscillations. The fit values and limits of combinations of SME coefficients are provided.
Address [Dharmapalan, R.; Liu, Y.; Perevalov, D.; Stancu, I.] Univ Alabama, Tuscaloosa, AL 35487 USA, Email: katori@fnal.gov
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000314554300015 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1390
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Author Double Chooz collaboration (Abrahao, T. et al); Novella, P.
Title Novel event classification based on spectral analysis of scintillation waveforms in Double Chooz Type Journal Article
Year 2018 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.
Volume 13 Issue Pages (down) P01031 - 26pp
Keywords Digital signal processing (DSP); Particle identification methods; Scintillators, scintillation and light emission processes (solid, gas and liquid scintillators); Neutrino detectors
Abstract Liquid scintillators are a common choice for neutrino physics experiments, but their capabilities to perform background rejection by scintillation pulse shape discrimination is generally limited in large detectors. This paper describes a novel approach for a pulse shape based event classification developed in the context of the Double Chooz reactor antineutrino experiment. Unlike previous implementations, this method uses the Fourier power spectra of the scintillation pulse shapes to obtain event-wise information. A classification variable built from spectral information was able to achieve an unprecedented performance, despite the lack of optimization at the detector design level. Several examples of event classification are provided, ranging from differentiation between the detector volumes and an efficient rejection of instrumental light noise, to some sensitivity to the particle type, such as stopping muons, ortho-positronium formation, alpha particles as well as electrons and positrons. In combination with other techniques the method is expected to allow for a versatile and more efficient background rejection in the future, especially if detector optimization is taken into account at the design level.
Address [Abrahao, T.; dos Anjos, J. C.; Lima, H.; Pepe, I.; Wagner, S.] Ctr Brasileiro Pesquisas Fis, BR-22290180 Rio De Janeiro, Brazil, Email: stefan.wagner@apc.in2p3.fr
Corporate Author Thesis
Publisher 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 1748-0221 ISBN Medium
Area Expedition Conference
Notes WOS:000423783800003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3466
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Author ANTARES Collaboration (Albert, A. et al); Barrios-Marti, J.; Hernandez-Rey, J.J.; Illuminati, G.; Lotze, M.; Tönnis, C.; Zornoza, J.D.; Zuñiga, J.
Title Search for high-energy neutrinos from bright GRBs with ANTARES Type Journal Article
Year 2017 Publication Monthly Notices of the Royal Astronomical Society Abbreviated Journal Mon. Not. Roy. Astron. Soc.
Volume 469 Issue 1 Pages (down) 906-915
Keywords acceleration of particles; neutrinos; gamma-ray burst: individual: GRB 080916C; gamma-ray burst: individual: GRB 110918A; gamma-ray burst: individual: GRB 130427A; gamma-ray burst: individual: GRB 130505A
Abstract Gamma-ray bursts are thought to be sites of hadronic acceleration, thus neutrinos are expected from the decay of charged particles, produced in p gamma interactions. The methods and results of a search for muon neutrinos in the data of the ANTARES neutrino telescope from four bright GRBs (GRB 080916C, GRB 110918A, GRB 130427A and GRB 130505A) observed between 2008 and 2013 are presented. Two scenarios of the fireball model have been investigated: the internal shock scenario, leading to the production of neutrinos with energies mainly above 100 TeV, and the photospheric scenario, characterized by a low-energy component in neutrino spectra due to the assumption of neutrino production closer to the central engine. Since no neutrino events have been detected in temporal and spatial coincidence with these bursts, upper limits at 90 per cent confidence level on the expected neutrino fluxes are derived. The non-detection allows for directly constraining the bulk Lorentz factor of the jet Gamma and the baryon loading f(p).
Address [Albert, A.; Drouhin, D.; Racca, C.] Univ Haute Alsace, GRPHE, Inst Univ Technol Colmar, 34 Rue Grillenbreit BP 50568, F-68008 Colmar, France, Email: silvia.celli@gssi.infn.it
Corporate Author Thesis
Publisher Oxford Univ Press Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0035-8711 ISBN Medium
Area Expedition Conference
Notes WOS:000402825000062 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3159
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Author ANTARES Collaboration (van Haren, H. et al); Aguilar, J.A.; Bigongiari, C.; Dornic, D.; Emanuele, U.; Gomez-Gonzalez, J.P.; Hernandez-Rey, J.J.; Mangano, S.; Salesa, F.; Toscano, S.; Yepes, H.; Zornoza, J.D.; Zuñiga, J.
Title Acoustic and optical variations during rapid downward motion episodes in the deep north-western Mediterranean Sea Type Journal Article
Year 2011 Publication Deep-Sea Research Part I-Oceanographic Research Papers Abbreviated Journal Deep-Sea Res. Part I-Oceanogr. Res. Pap.
Volume 58 Issue 8 Pages (down) 875-884
Keywords Acoustic ADCP observations; Optical photo-multiplier observations; Deep Mediteranean; ANTARES neutrino telescope; Episodic downward current; Bioluminescence; Dense water formation; Northern boundary current
Abstract An Acoustic Doppler Current Profiler (ADCP) was moored at the deep-sea site of the ANTARES neutrino telescope near Toulon, France, thus providing a unique opportunity to compare high-resolution acoustic and optical observations between 70 and 170 m above the sea bed at 2475 m. The ADCP measured downward vertical currents of magnitudes up to 0.03 m s(-1) in late winter and early spring 2006. In the same period, observations were made of enhanced levels of acoustic reflection, interpreted as suspended particles including zooplankton, by a factor of about 10 and of horizontal currents reaching 0.35 m s(-1). These observations coincided with high light levels detected by the telescope, interpreted as increased bioluminescence. During winter 2006 deep dense-water formation occurred in the Ligurian subbasin, thus providing a possible explanation for these observations. However, the 10-20 days quasi-periodic episodes of high levels of acoustic reflection, light and large vertical currents continuing into the summer are not direct evidence of this process. It is hypothesized that the main process allowing for suspended material to be moved vertically later in the year is local advection, linked with topographic boundary current instabilities along the rim of the 'Northern Current'.
Address [van Haren, H] Royal Netherlands Inst Sea Res NIOZ, NL-1797 SZ T Horntje, Texel, Netherlands, Email: hans.van.haren@nioz.nl
Corporate Author Thesis
Publisher 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 0967-0637 ISBN Medium
Area Expedition Conference
Notes WOS:000295115400006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 770
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