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Author de Salas, P.F.; Pastor, S.
Title Relic neutrino decoupling with flavour oscillations revisited Type Journal Article
Year 2016 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 07 Issue 7 Pages 051 - 18pp
Keywords cosmological neutrinos; particle physics – cosmology connection; physics of the; early universe; neutrino properties
Abstract We study the decoupling process of neutrinos in the early universe in the presence of three-flavour oscillations. The evolution of the neutrino spectra is found by solving the corresponding momentum-dependent kinetic equations for the neutrino density matrix, including for the first time the proper collision integrals for both diagonal and off-diagonal elements. This improved calculation modifies the evolution of the off-diagonal elements of the neutrino density matrix and changes the deviation from equilibrium of the frozen neutrino spectra. However, it does not vary the contribution of neutrinos to the cosmological energy density in the form of radiation, usually expressed in terms of the effective number of neutrinos, N-eff. We find a value of N-eff = 3.045, in agreement with previous theoretical calculations and consistent with the latest analysis of Planck data. This result does not depend on the ordering of neutrino masses. We also consider the effect of non-standard neutrino-electron interactions (NSI), predicted in many theoretical models where neutrinos acquire mass. For two sets of NSI parameters allowed by present data, we find that Neff can be reduced down to 3.040 or enhanced up to 3.059.
Address [de Salas, Pablo F.; Pastor, Sergio] Univ Valencia, CSIC, Inst Fis Corpuscular, Parc Cient UV,C Catedrat Jose Beltran 2, E-46980 Paterna, Valencia, Spain, Email: pabrerde@ific.uv.es;
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 1475-7516 ISBN Medium
Area Expedition Conference
Notes WOS:000381830000052 Approved no
Is ISI yes International Collaboration (up) no
Call Number IFIC @ pastor @ Serial 2784
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Author De Romeri, V.; Fernandez-Martinez, E.; Sorel, M.
Title Neutrino oscillations at DUNE with improved energy reconstruction Type Journal Article
Year 2016 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 09 Issue 9 Pages 030 - 25pp
Keywords CP violation; Neutrino Physics
Abstract We study the physics reach of the long-baseline oscillation analysis of the DUNE experiment when realistic simulations are used to estimate its neutrino energy reconstruction capabilities. Our studies indicate that significant improvements in energy resolution compared to what is customarily assumed are plausible. This improved energy resolution can increase the sensitivity to leptonic CP violation in two ways. On the one hand, the CP-violating term in the oscillation probability has a characteristic energy dependence that can be better reproduced. On the other hand, the second oscillation maximum, especially sensitive to delta(CP), is better reconstructed. These effects lead to a significant improvement in the fraction of values of delta(CP) for which a 5 sigma discovery of leptonic CP-violation would be possible. The precision of the delta(CP) measurement could also be greatly enhanced, with a reduction of the maximum uncertainties from 26 degrees to 18 degrees for a 300 MW.kt.yr exposure. We therefore believe that this potential gain in physics reach merits further investigations of the detector performance achievable in DUNE.
Address [De Romeri, Valentina; Fernandez-Martinez, Enrique] Univ Autonoma Madrid, Dept Fis Teor, E-28049 Madrid, Spain, Email: valentina.deromeri@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:000382887300001 Approved no
Is ISI yes International Collaboration (up) no
Call Number IFIC @ pastor @ Serial 2807
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Author Pich, A.; Rodriguez-Sanchez, A.
Title Updated determination of alpha(s)(m(tau)(2)) from tau decays Type Journal Article
Year 2016 Publication Modern Physics Letters A Abbreviated Journal Mod. Phys. Lett. A
Volume 31 Issue 30 Pages 1630032 - 15pp
Keywords QCD; strong coupling; tau decays
Abstract Using the most recent release of the ALEPH tau decay data, we present a very detailed phenomenological update of the alpha(s)(m(tau)(2)) determination. We have exploited the sensitivity to the strong coupling in many different ways, exploring several complementary methodologies. All determinations turn out to be in excellent agreement, allowing us to extract a very reliable value of the strong coupling. We find alpha((nf =3))(s)(m(tau)(2)) = 0.328 +/- 0.012 which implies alpha((nf=5))(s)(M-Z(2)) = 0.1197 +/- 0.0014. We critically revise previous work, and point out the problems flawing some recent analyses which claim slightly smaller values.
Address [Pich, Antonio; Rodriguez-Sanchez, Antonio] Univ Valencia, IFIC, CSIC, Dept Fis Teor, Apt Correus 22085, F-46071 Valencia, Spain, Email: Antonio.Pich@ific.uv.es;
Corporate Author Thesis
Publisher World Scientific Publ Co Pte Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0217-7323 ISBN Medium
Area Expedition Conference
Notes WOS:000383788500002 Approved no
Is ISI yes International Collaboration (up) no
Call Number IFIC @ pastor @ Serial 2818
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Author Sborlini, G.F.R.; Driencourt-Mangin, F.; Rodrigo, G.
Title Four-dimensional unsubtraction with massive particles Type Journal Article
Year 2016 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 10 Issue 10 Pages 162 - 34pp
Keywords NLO Computations
Abstract We extend the four-dimensional unsubtraction method, which is based on the loop-tree duality (LTD), to deal with processes involving heavy particles. The method allows to perform the summation over degenerate IR configurations directly at integrand level in such a way that NLO corrections can be implemented directly in four space-time dimensions. We define a general momentum mapping between the real and virtual kinematics that accounts properly for the quasi-collinear configurations, and leads to an smooth massless limit. We illustrate the method first with a scalar toy example, and then analyse the case of the decay of a scalar or vector boson into a pair of massive quarks. The results presented in this paper are suitable for the application of the method to any multipartonic process.
Address [Sborlini, German F. R.; Driencourt-Mangin, Felix; Rodrigo, German] Univ Valencia, CSIC, Inst Fis Corpuscular, Parc Cient, E-46980 Valencia, Spain, Email: german.sborlini@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:000387374000001 Approved no
Is ISI yes International Collaboration (up) no
Call Number IFIC @ pastor @ Serial 2853
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Author Ayala, C.; Gonzalez, P.; Vento, V.
Title Heavy quark potential from QCD-related effective coupling Type Journal Article
Year 2016 Publication Journal of Physics G Abbreviated Journal J. Phys. G
Volume 43 Issue 12 Pages 125002 - 12pp
Keywords general properties of QCD; potential models; other non-perturbative calculations; heavy quarkonia
Abstract We implement our past investigations of quark-antiquark interaction through a non-perturbative running coupling defined in terms of a gluon mass function, similar to that used in some Schwinger-Dyson approaches. This coupling leads to a quark-antiquark potential, which satisfies not only asymptotic freedom but also describes linear confinement correctly. From this potential, we calculate the bottomonium and charmonium spectra below the first open flavor meson-meson thresholds and show that for a small range of values of the free parameter determining the gluon mass function an excellent agreement with data is attained.
Address [Gonzalez, Pedro] Univ Valencia, Dept Theoret Phys, E-46100 Valencia, Spain, Email: Pedro.Gonzalez@uv.es
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 0954-3899 ISBN Medium
Area Expedition Conference
Notes WOS:000388219700001 Approved no
Is ISI yes International Collaboration (up) no
Call Number IFIC @ pastor @ Serial 2870
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