A Short Travel for Neutrinos in Large Extra Dimensions

Neutrino oscillations successfully explain the flavor transitions observed in neutrinos produced in natural sources like the center of the sun and the earth atmosphere, and also from man-made sources like reactors and accelerators. These oscillations are driven by two mass-squared differences, solar and atmospheric, at the sub-eV scale. However, longstanding anomalies at short-baselines might imply the existence of new oscillation frequencies at the eV-scale and the possibility of this sterile state(s) to mix with the three active neutrinos. One of the many future neutrino programs that are expected to provide a final word on this issue is the Short-Baseline Neutrino Program (SBN) at FERMILAB. In this letter, we consider a specific model of Large Extra Dimensions (LED) which provides interesting signatures of oscillation of extra sterile states. We started re-creating sensitivity analyses for sterile neutrinos in the 3+1 scenario, previously done by the SBN collaboration, by simulating neutrino events in the three SBN detectors from both muon neutrino disappearance and electron neutrino appearance. Then, we implemented neutrino oscillations as predicted in the LED model and also we have performed sensitivity analysis to the LED parameters. Finally, we studied the SBN power of discriminating between the two models, the 3+1 and the LED. We have found that SBN is sensitive to the oscillations predicted in the LED model and have the potential to constrain the LED parameter space better than any other oscillation experiment, for $m_{1}^D<0.1\,\text{eV}$. In case SBN observes a departure from the three active neutrino framework, it also has the power of discriminating between sterile oscillations predicted in the 3+1 framework and the LED ones.Comment: 21 pages, 6 figures, 2 table

On the description of non-unitary neutrino mixing

Neutrino oscillations are well established and the relevant parameters determined with good precision, except for the CP phase, in terms of a unitary lepton mixing matrix. Seesaw extensions of the Standard Model predict unitarity deviations due to the admixture of heavy isosinglet neutrinos. We provide a complete description of the unitarity and universality deviations in the light neutrino sector. Neutrino oscillation experiments involving electron or muon neutrinos and anti-neutrinos are fully described in terms of just three new real parameters and a new CP phase, in addition to the ones describing oscillations with unitary mixing. Using this formalism we describe the implications of non-unitarity for neutrino oscillations and summarize the model-independent constraints on heavy neutrino couplings that arise from current experiments.Comment: 28 pages, 8 figures, typos corrected, modified bounds on non-unitarity parameters, new figs 3 and

Huella de carbono de los sitemas de producci?n del centro universitario regional del norte (CURDN) de la Universidad del Tolima, Armero - Guayabal, Tolima Colombia

83 p. Recurso Electr?nicoEl cambio clim?tico es ocasionado por el aumento en las concentraciones de gases de efecto de invernadero. El objetivo de este estudio fue estimar la huella de carbono del Centro Universitario Regional del Norte (CURDN), Armero, Guayabal. La huella de carbono se estim? como la diferencia entre la fijaci?n de carbono en biomasa y las emisiones de gases de efecto invernadero. Se establecieron 44 parcelas temporales de muestreo en los diferentes usos del suelo donde se midi? todos los ?rboles con di?metro del tronco a la altura del pecho > 10 cm y plantas de cacao. Se emplearon modelos alom?tricos y factores de expansi?n de biomasa, la fracci?n de carbono (0,5) y se calcul? el CO2e. Se estim? la fijaci?n de los sistemas productivos en biomasa de le?osas perennes considerando el almacenamiento de carbono y la edad. Se indag?, mediante encuestas semi-estructuradas, las actividades de manejo en los sistemas productivos y del ?rea administrativa que emiten gases de efecto invernadero. La huella de carbono del CURDN fue positiva (1575,7 t CO2e/a?o), es decir, la fijaci?n es mayor que las emisiones de gases de efecto invernadero. Se encontr? que los sistemas de producci?n agr?colas y pecuarios son emisores netos de ?stos gases (1,1 y 2,8 t CO2e/ha/a?o, respectivamente); mientras que los sistemas forestales fijan netamente 14,0 t CO2e/ha/a?o. Los resultados muestran que el CURDN es carbono neutro y podr?a eventualmente vender cr?ditos de carbono, adicionalmente se muestra la importancia de los componentes le?osos como sumideros de carbono para la mitigaci?n del cambio clim?tico. Palabras clave: Cambio clim?tico, huella carbono, fijaci?n de carbono, emisi?n gases de efecto invernadero, modelos alometricosThe climate change is caused by the increase of greenhouse gases. The objective of this study was to estimate the carbon footprint in the Centro Universitario Regional del Norte (CURDN), Armero, Guayabal. The carbon footprint was estimated as the difference between carbon fixation in biomass and the emission of greenhouse gases. A total of 44 temporal sampling plots in the different land uses where all trees with diameter of trunk at the breast height > 10 cm and cacao plants. Alometric models and biomass expansion factors and the carbon fraction (0.5) were employed and CO2e was calculated. It was estimated the fixation of the productive systems in biomass of woody perennial plants considering carbon storage and age. It was consulted, throught semi-estructured interviews, the activity management in the productive systems and the administrative area that emit greenhouse gases. The carbon footprint of the CURDN was positive (1575.7 t CO2e/year), in other words, the fixation is higher tan emissions. It was found that agriculture and cattle productive systems are net emisors (1.1 and 2.8 t CO2e/ha/year, respectively); whereas the forestry systems anually fix 14.0 t CO2e/ha/year. The results show that CURDN is carbon neutral and it could sale carbon credits, additionally it is shown the importance of woody components as carbon sinks for climate change mitigation. Keywords: Climate change, carbon footprint, carbon fixation, emission of greenhouse gases, allometric models

Ceba de novillos en pasto pará (Brachiaria mutica Forsk, Stapf) con rotación de potreros y fertilización nitrogenada.

Maestría en CienciasMaestrí

Reciclaje antiguo seminario Villanueva

No dispon

A short travel for neutrinos in large extra dimensions

FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICONeutrino oscillations successfully explain the flavor transitions observed in neutrinos produced in natural sources like the center of the sun and the earth atmosphere, and also from man-made sources like reactors and accelerators. These oscillations are driven by two mass-squared differences, solar and atmospheric, at the sub-eV scale. However, longstanding anomalies at short-baselines might imply the existence of new oscillation frequencies at the eV-scale and the possibility of this sterile state(s) to mix with the three active neutrinos. One of the many future neutrino programs that are expected to provide a final word on this issue is the Short-Baseline Neutrino Program (SBN) at FERMILAB. In this letter, we consider a specific model of Large Extra Dimensions (LED) which provides interesting signatures of oscillation of extra sterile states. We started re-creating sensitivity analyses for sterile neutrinos in the 3+1 scenario, previously done by the SBN collaboration, by simulating neutrino events in the three SBN detectors from both muon neutrino disappearance and electron neutrino appearance. Then, we implemented neutrino oscillations as predicted in the LED model and also we have performed sensitivity analysis to the LED parameters. Finally, we studied the SBN power of discriminating between the two models, the 3+1 and the LED. We have found that SBN is sensitive to the oscillations predicted in the LED model and have the potential to constrain the LED parameter space better than any other oscillation experiment for m1 D < 0.1 eV. In case SBN observes a departure from the three active neutrino framework, it also has the power of discriminating between sterile oscillations predicted in the 3+1 framework and the LED ones.11121FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO2014/19164-62016/00272-92016/08308-22017/12904-22017/01749-6307269/2013-2304715/2016-

Two-parameter neutrino mass matrices with two texture zeros

We reanalyse Majorana-neutrino mass matrices M_nu with two texture zeros, by searching for viable hybrid textures in which the non-zero matrix elements of M_nu have simple ratios. Referring to the classification scheme of Frampton, Glashow and Marfatia, we find that the mass matrix denoted by A1 allows the ratios (M_nu)_{mu mu} : (Mnu)_{tau tau} = 1:1 and (M_nu)_{e tau} : (Mnu)_{mu tau} = 1:2. There are analogous ratios for texture A2. With these two hybrid textures, one obtains, for instance, good agreement with the data if one computes the three mixing angles in terms of the experimentally determined mass-squared differences Delta m^2_21 and Delta m^2_31. We could not find viable hybrid textures based on mass matrices different from those of cases A1 and A2.Comment: 10 pages, no figures, minor changes, some references adde

Correlations of the elements of the neutrino mass matrix

Assuming Majorana nature of neutrinos, we re-investigate, in the light of the recent measurement of the reactor mixing angle, the allowed ranges for the absolute values of the elements of the neutrino mass matrix in the basis where the charged-lepton mass matrix is diagonal. Apart from the derivation of upper and lower bounds on the values of the matrix elements, we also study their correlations. Moreover, we analyse the sensitivity of bounds and correlations to the global fit results of the neutrino oscillation parameters which are available in the literature.Comment: 37 pages, 146 figures, minor corrections, 17 additional figures, version for publication in JHE

Analysis of short-period internal waves using wave-induced surface displacement: A three-dimensional model approach in Algeciras Bay and the Strait of Gibraltar

A three-dimensional, nonlinear, high-resolution, sigma coordinate, hydrodynamic model was applied to study the sea surface manifestation of short-period internal waves measured in Algeciras Bay and the Strait of Gibraltar. Model results reproduce the tidally induced generation of the internal bore over the Camarinal Sill and its disintegration into wave trains as it moves eastward. While propagating along the Strait of Gibraltar toward the Mediterranean Sea, the wave trains partly penetrate into Algeciras Bay, with typical oscillation periods of 20 and 40 min. The modeled wave-induced surface train structures are compared with satellite images and in situ observational data obtained from two pressure sensors located inside the bay. Results demonstrate that wave-induced sea surface displacements are indicators of the presence of internal waves and may be used in the context of the internal wave analysis when surface oscillations are captured with sufficient precision