Construcción de un equipo de medida de fotosíntesis neta y transpiración para plantas individuales

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Anundo Polanía

2010-01-01

Full Text Available Se construyó un equipo de medida de fotosíntesis neta y transpiración para plantas individuales jóvenes de sistema abierto. La parte aérea de la planta se introdujo en una cámara transparente con un sistema de entrada y salida de aire. Esta tenía un control de temperatura y ventilación y estaba iluminada por varias bombillas cuya distancia a la cámara era graduable.Un analizador de gases infrarrojo midió la diferencia de concentración de CO2 entre la entrada y la salida de la cámara. La humedad del aire era registrada por unhigrómetro de punto de rocío. La concentración de CO2 y H2O en el aire que entraba a la cámara era controlada usando trampas selectivas y saturadores de vapor de agua. Con el equipo se hicieron medidas de ratas de fotosíntesis neta y transpiración en plantas de maíz. La precisión y la reproducibilidad de las medidas obtenidas con el equipo permiten su utilización para estudios del mismo tipo en otrasespecies.

Medida de espessura de filmes finos com interferometro de haidinger

OpenAIRE

Elisabeth Andreoli de Oliveira

1987-01-01

Resumo: Apresentamos um método não destrutivo para medida de espessura de filmes finos transparentes depositados em substratos transparentes, usando um interferômetro de Haidinger. A partir das frações de interferência, medidas para vários comprimentos de onda, e do índice de refração para um único comprimento de onda, determinamos a espessura do filme e sua dispersão cromática, através de um procedimento analítico-numérico Abstract: We introduce a non-destructive method for the thickness ...

Medidas de pobreza: un enfoque alternativo

OpenAIRE

Lazzari, Luisa L; Fernández, María José

2006-01-01

Una medida creíble de pobreza e indigencia puede ser un poderoso instrumento para concentrar la atención del policymaker en las condiciones de vida de los pobres. Las opciones elegidas para fijarlas tienen gran importancia para las decisiones políticas a tomar. El método indirecto o enfoque del ingreso parte de la valorización de una Canasta Básica Alimentaria (CBA) que determina la cantidad de calorías mínimas necesarias para satisfacer las necesidades biológicas básicas de...

Elaboração de uma hipermídia educacional para o ensino do procedimento de medida da pressão arterial

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Debora Cristina Alavarce

2011-08-01

Full Text Available A medida da pressão arterial é um procedimento imprescindível na avaliação do sistema cardiovascular. O ambiente digital de aprendizagem tem-se constituído em uma poderosa ferramenta do processo de ensino aprendizagem, pois acrescenta significado e concretude aos conteúdos que precisam ser aprendidos, podendo ser útil para o ensino deste procedimento. O objetivo deste trabalho foi construir uma hipermídia educacional para o ensino da técnica de medida da pressão arterial e descrever as etapas do processo de construção. O referencial pedagógico adotado foi o de Robert Gagné; para a construção, segue-se o modelo proposto por Price. O produto final apresenta vídeos, fotos, animações e simulações demonstrando e ensinando a realização do procedimento. Embora a construção da hipermídia tenha sido complexa, sua utilização pode incrementar positivamente o ensino de procedimentos de enfermagem.

ADOLESCENTES EM CONFLITO COM A LEI EM MOÇAMBIQUE: REFLEXÕES SOBRE MEDIDAS SOCIOEDUCATIVAS E LIMITES PARA SUA APLICAÇÃO PRÁTICA.

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Tomás Xavier Francisco

2015-03-01

Full Text Available Este artigo tem por fim analisar, por um lado, a problemática dos adolescentes em conflito com a lei em Moçambique, e por outro lado, fazer reflexões sobre as medidas socioeducativas e limites para a sua aplicação prática. O trabalho contempla uma introdução, desenvolvimento onde arrola-se considerações sobre o histórico da legislação sobre adolescentes ou menores no país, reflexões sobre medidas socioeducativas e seus limites para sua aplicação prática, e por fim, contempla considerações finais e referências bibliográficas. A metodologia usada foi estudo exploratório, recorrendo-se a pesquisa bibliográfica e análise documental.

Resonancia magnética cardiaca: medidas lineales y volumétricas en adultos sanos

OpenAIRE

Heredia Sánchez, Fabian Mauricio; Cabezas, Andrés Mauricio

2015-01-01

Introducción: La gran mayoría de las medidas de normalidad utilizadas para la interpretación de resonancia cardiaca son extrapoladas de las medidas de ecocardiografía. Los limitados registros de medidas de normalidad se encuentran ajustados en poblaciones extranjeras, no hay registros en latinoamericanos. Objetivo: Determinar las dimensiones cardiacas utilizando resonancia magnética en una población de personas sin antecedente médicos con repercusión cardiaca para lograr una muestra de val...

Método para obtenção de medidas antropométricas utilizando um digitalizador 3D de baixo custo

OpenAIRE

Clariana Fischer Bendler; Fábio Gonçalves Teixeira

2016-01-01

O objetivo é desenvolver um método para obtenção de medidas antropométricas através de um digitalizador 3D de baixo custo. A metodologia da pesquisa consiste em seis etapas: pesquisa bibliográfica, coleta e análise dos dados antropométricos pelo método direto e o desenvolvimento do método indireto de obtenção de medidas antropométricas, comparação e análise dos dados obtidos, discussão dos resultados e a finalização. O processo de digitalização utilizado está baseado em um dispositivo de baix...

LAS MEDIDAS URGENTES PARA LA REFORMA DEL MERCADO LABORAL: ASPECTOS LABORALES TRAS LA PROMULGACIÓN DE LA LEY 3/2012

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Esperanza Macarena Sierra Benítez

2013-05-01

Full Text Available La situación económica y de crisis en la zona euro obligó al Gobierno, en el año 2010, a iniciar una era de reformas estructurales de gran calado en ámbitos tan importantes como el financiero, y en particular el de la banca. En el ámbito laboral el periodo 2010-2012 se caracteriza por una producción importante de reformas que debería culminar con la Ley 3/2012, de 6 de julio, de medidas urgentes para la reforma laboral, objeto de este trabajo. El estudio contempla también el comienzo de la segunda generación de reformas estructurales, el Real Decreto-ley 4/2013, de 22 de febrero, de medidas de apoyo al emprendedor y de estímulo del crecimiento y de la creación de empleo, para finalizar con una mención al Real Decreto-ley 5/2013, de 15 de marzo, de medidas para favorecer la continuidad de la vida laboral de los trabajadores de mayor edad y promover el envejecimiento activo. Se trata de un comentario que ha atendido fundamentalmente al contenido laboral de la reforma del mercado de trabajo, dejando al margen el de la Seguridad Social, pero incluyendo el RD-ley 20/2012, de 13 de julio, de medidas para garantizar la estabilidad presupuestaria y de fomento de la competitividad. In 2010 the economical situation and the eurozone crisis forced the Spanish Government to commence an era of deep structural reforms in important areas such as finance, with special regard to the banking sector. In the labour sphere the period 2010-2012 is marked by a significant production of reforms that should culminate with the Law 3/2012, of July 6th, on urgent measures for labour reform, which is the aim of this essay. The study also includes the start of a second generation of structural reforms, the Royal Decree-Law 4/2013, of February 22nd, on support measures for entrepreneurs and incentives to growth and employment, and it finishes with a mention to the Royal Decree-Law 5/2013, of March 15th, on measures to keep older workers within the labour market

El trabajo en Smith: valor o medida del valor?

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Adolfo Rodríguez Herrera

2016-12-01

Este artículo revisa los conceptos desarrollados por Smith para formular su teoría del valor (valor, precio real y valor de  cambio. Nuestra interpretación de sus textos sobre el valor no coincide con la que tradicionalmente se ha hecho. De acuerdo con nuestra interpretación, no sería correcta la crítica de Ricardo y Marx a la posición de Smith sobre el papel del trabajo como medida de valor. Para estos autores, Smith no es consistente al proponer que el valor de una mercancía es definido o medido como la cantidad de trabajo necesaria para producirla y simultáneamente como la cantidad de trabajo que puede ser comprada por esta mercancía. Tratamos de demostrar que para Smith el trabajo tiene un doble papel –como fuente y como medida del valor–, y que a ello se debe la confusión generada por su uso de algunos términos: Smith propone el trabajo como una medida de valor porque lo concibe como una fuente de valor. Con esta interpretación queda claro, paradójicamente, que la teoría del valor trabajo de Smith corresponde sustancialmente con la que más tarde desarrollarán Ricardo y Marx.

Fusão INS/GNSS com auxílio de medidas de baseline e ângulo GNSS

OpenAIRE

Priscylla Angélica da Silva Oliveira

2014-01-01

Este trabalho investiga sistemas de navegação INS/GNSS auxiliado por medidas de baseline e ângulo GNSS. Os dados gerados para as simulações foram os dados IMU, dados GNSS e informações de baseline e ângulo GNSS. Estas informações, determinadas a partir de um sistema multiantenas para o posicionamento simples e relativo e no método direto, respectivamente, foram utilizadas como medidas auxiliares para a fusão INS/GNSS. Foi estudada a influência dessas medidas auxiliares nas estimativas de atit...

Estudio de medidas y proyectos de movilidad ambiental en el entorno europeo

OpenAIRE

Moya González, Luis

2011-01-01

Índice Introducción Tablas resumen de medidas ambientales sobre movilidad Medidas específicas para ciudades históricas Mejora del transporte públicoGestión de automóvilesVehículos compartidosInnovación en vehículos y carburantesTransporte de mercancíasBicicletasPeatonesGestión: demanda, incentivos, etcOtras medidasMedidas coordinadas y planes integrales Experiencias europeasLa situación en EspañaProgramas y proyectos subvencionados Programas de la Unión EuropeaProyectos internacionales no vin...

Método para obtenção de medidas antropométricas utilizando um digitalizador 3D de baixo custo

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Clariana Fischer Bendler

2016-09-01

Full Text Available O objetivo é desenvolver um método para obtenção de medidas antropométricas através de um digitalizador 3D de baixo custo. A metodologia da pesquisa consiste em seis etapas: pesquisa bibliográfica, coleta e análise dos dados antropométricos pelo método direto e o desenvolvimento do método indireto de obtenção de medidas antropométricas, comparação e análise dos dados obtidos, discussão dos resultados e a finalização. O processo de digitalização utilizado está baseado em um dispositivo de baixo custo, o Microsoft Kinect e no software kscan3D. Para o levantamento antropométrico a partir do modelo tridimensional, é utilizado o software Autodesk 3D Studio Max. A pesquisa apresenta recomendações e restrições para a geração do modelo tridimensional, de forma a se obter uma malha com precisão satisfatória. É apresentado um fluxograma para orientar a aplicação do método desenvolvido no processo de Design bem como um quadro-resumo contendo diretrizes para esta aplicação. O método desenvolvido obteve 97,96% de compatibilidade nos resultados das variáveis mensuradas em relação ao método direto. Estes resultados foram obtidos com um tempo de exposição do indivíduo de apenas 3 minutos e 28 segundos, muito inferior ao tempo necessário no método direto, que foi de 1 hora e 12 minutos, o que demonstra uma das principais contribuições do método proposto.

Método para obtenção de medidas antropométricas utilizando um digitalizador 3D de baixo custo

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Clariana Fischer Brendler

2016-08-01

Full Text Available O objetivo é desenvolver um método para obtenção de medidas antropométricas através de um digitalizador 3D de baixo custo. A metodologia da pesquisa consiste em seis etapas: pesquisa bibliográfica, coleta e análise dos dados antropométricos pelo método direto e o desenvolvimento do método indireto de obtenção de medidas antropométricas, comparação e análise dos dados obtidos, discussão dos resultados e a finalização. O processo de digitalização utilizado está baseado em um dispositivo de baixo custo, o Microsoft Kinect e no software kscan3D. Para o levantamento antropométrico a partir do modelo tridimensional, é utilizado o software Autodesk 3D Studio Max. A pesquisa apresenta recomendações e restrições para a geração do modelo tridimensional, de forma a se obter uma malha com precisão satisfatória. É apresentado um fluxograma para orientar a aplicação do método desenvolvido no processo de Design bem como um quadro-resumo contendo diretrizes para esta aplicação. O método desenvolvido obteve 97,96% de compatibilidade nos resultados das variáveis mensuradas em relação ao método direto. Estes resultados foram obtidos com um tempo de exposição do indivíduo de apenas 3 minutos e 28 segundos, muito inferior ao tempo necessário no método direto, que foi de 1 hora e 12 minutos, o que demonstra uma das principais contribuições do método proposto.

Adolescente que cumpre medida socioeducativa: modos de ser no cotidiano e possibilidades para enfermagem Adolescente que cumple medida socioeducativa: modos de ser en el cotidiano y posibilidades para la enfermería Adolescents under semi-freedom social-educative measure: everyday ways of being and possibilities for nursing

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Dilce Rejane Peres do Carmo

2011-09-01

Full Text Available Objetivou compreender o cotidiano do ser-adolescente que cumpre medida socioeducativa de semiliberdade. Investigação fenomenológica, desenvolvida em unidade da Fundação de Atendimento Socioeducativo, no Rio Grande do Sul. A entrevista foi desenvolvida com nove adolescentes, entre fevereiro e maio de 2009. A análise heideggeriana des-velou que vivenciar a medida socioeducativa significa uma prisão, algo ruim. Sabe que não está no sistema penitenciário por conta da idade e re-conhece que jogou fora sua adolescência. Na instituição vai à escola para aprender algo, para arrumar algum trabalho. Mostra-se no modo de ser do falatório, ambiguidade e ocupação. Conclui-se que o adolescente está-lançado naquilo que está determinado, mantém-se na impessoalidade. Para reinserção social precisa de ajuda do sistema socioeducativo, mediado pelo trabalho interdisciplinar, rede de apoio de co-responsabilidade da família, comunidade e Estado.Se tuvo como objetivo comprender el cotidiano del ser-adolescente que cumple medida socioeducativa de semilibertad. Investigación fenomenológica, desarrollada en una unidad de la Fundación de Atención Socioeducativo, en el Río Grande del Sur, Brasil. La entrevista fue desarrollada con nueve adolescentes, entre febrero y mayo de 2009. El análisis heideggeriano des-veló que vivenciar la medida socioeducativa significa una prisión, algo malo. Sabe que no está en el sistema penitenciario debido a la edad y re-conoce que se le echó su adolescencia. En la institución va a la escuela para aprender algo, para lograr algún trabajo. Se muestra en el modo de ser de la habladuría, ambigüedad y ocupación. Se concluye que el adolescente está lanzado en aquello que está determinado, se mantiene en la impersonalidad. Para reinserción social necesita de ayuda del sistema socioeducativo, mediado por el trabajo interdisciplinar, red de apoyo de co-responsabilidad de la familia, comunidad y Estado

Menores em conflito com a lei em Moçambique: reflexões sobre medidas socioeducativas e limites para sua aplicação prática

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Tomás Xavier Francisco

2014-06-01

Full Text Available Este artigo tem por fim analisar, por um lado, a problemática dos adolescentes em conflito com a lei em Moçambique, e por outro lado, fazer reflexões sobre as medidas socioeducativas e limites para a sua aplicação prática. O trabalho contempla uma introdução, desenvolvimento onde arrola-se considerações sobre o histórico da legislação sobre adolescentes ou menores no país, reflexões sobre medidas socioeducativas e seus limites para sua aplicação prática, e por fim, contempla considerações finais e referências bibliográficas. A metodologia usada foi estudo exploratório, recorrendo-se a pesquisa bibliográfica e análise documental.

Suspensão da execução de medidas judiciais deferidas para a tutela de interesses ambientais

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José Mauro

2014-07-01

Full Text Available O instituto denominado Suspensão de Segurança, que permite suspender os efeitos de decisões judiciais deferidas contra o Poder Público, demanda adequação no que se refere à sua aplicação para suspender medidas deferidas para a tutela de interesses ambientais. A sua adequação aos princípios da inafastabilidade da jurisdição, da efetividade da tutela jurisdicional e do desenvolvimento sustentável pode ser procedida mediante a realização, no processo de suspensão, da ponderação entre o interesse ambiental e a ameaça de lesão ao interesse do Poder Público, com vistas a determinar, no caso concreto, qual deles deve prevalecer.

Medida da visão em candelas: description of a psychophysical technique to quantify luminous intensity

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Airton Leite Kronbauer

2011-04-01

Full Text Available OBJETIVO: Desenvolver um método e um dispositivo para quantificar a visão em candela (cd. Os estudos de medida da visão são importantes para todas as ciências visuais. MÉTODOS: É um estudo teórico e experimental. Foram descritos os detalhes do método psicofísico e da calibração do dispositivo. Foram realizados testes preliminares em voluntários. RESULTADOS: É um teste psicofísico simples e com resultado expresso em unidades do sistema internacional de medidas. Com a descrição técnica será possível reproduzir o experimento em outros centros de pesquisa. CONCLUSÃO: Os resultados aferidos em intensidade luminosa (cd são uma opção para estudo visual. Esses resultados possibilitarão extrapolar medidas para modelos matemáticos e para simular efeitos individuais com dados aberrométricos.

Ilustração de incertezas em medidas utilizando experimentos de queda livre

OpenAIRE

Coluci,Vitor R.; Paulino,Guilherme; Souza,Diego C. de; Vasconcelos,Elba P.R.

2013-01-01

O conhecimento da incerteza de uma medida é crucial para obter conclusões a partir de resultados experimentais. Erros aleatórios, comuns em experimentos, produzem uma distribuição dos valores medidos que segue o formato gaussiano. Neste trabalho desenvolvemos uma montagem baseada no fenômeno de queda livre para auxiliar na ilustração do conceito de incerteza em medidas. Os tempos de queda de um objeto foram obtidos automaticamente pela placa Arduino e exibidos na forma de um histograma na tel...

Medidas de bioseguridad adoptadas en el manejo con materiales biológicos en Laboratorios Liorad

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Nancy Burguet Lago

2013-03-01

Full Text Available Introducción: el trabajo con microorganismos puede conllevar a riesgos tanto para el personal que trabaja con los mismos como para el medio ambiente. La existencia de laboratorios de seguridad biológica y la implementación de medidas en la manipulación de los agentes biológicos minimizan el riesgo. Objetivo: evaluar las medidas de bioseguridad adoptadas en el manejo con materiales biológicos en Laboratorios Liorad. Métodos: empleo de una lista de chequeo y análisis de los resultados a través de una Matriz DAFO para valorar si el diseño de la instalación cumple con la bioseguridad. Además establecer un sistema documental para la manipulación de microorganismos y la confección de un plan de capacitación para el personal que trabaja en el laboratorio de control microbiológico. Resultados: la lista de chequeo permitió identificar como principal debilidad el no disponer de un doble pasillo para el traslado del material limpio y sucio. Como fortalezas, cumplir con las prácticas y procesamientos adecuados y el contar con equipos de seguridad biológica. El sistema documental incorporó a los procedimientos establecidos para la manipulación, un acápite referido a la «Peligrosidad y Medidas de Seguridad». El programa de capacitación desarrollado permitió proveer conocimientos específicos referidos a esta temática. Conclusión: las medidas adoptadas en el laboratorio permiten plantear que de manera general se cumplen los requisitos establecidos en materia de Bioseguridad para el trabajo con microorganismos.

Hacia una definición de la medida

OpenAIRE

Parot, Jean Jacques

2012-01-01

Hacia una definición de la medida A. Primera situación Un granjero va al mercado para vender a) Una gallina (20 pesos) b) Un bulto de naranjas (45 pesos) c) Un pate (38 pesos) d) Una docena de huevos (12 pesos)

Implementación de medidas de bioseguridad en granjas de broilers para reducir la prevalencia de Campylobacter: cuestiones prácticas, problemas y soluciones

DEFF Research Database (Denmark)

Cerda-Cuellar, M.; Laureano, L.; Corujo, A.

Actualmente, la implementación y mejora de las medidas de bioseguridad en granjas de broilers a nivel de nave es la una de las principales herramientas disponibles para el control de Campylobacter en el primer eslabón de la cadena alimentaria. Una de las principales actuaciones a acometer implica...

Medidas de la felicidad nacional bruta

NARCIS (Netherlands)

R. Veenhoven (Ruut)

2009-01-01

textabstractResumen. La felicidad está abriéndose hueco en la agenda política, lo cual reclama medir el éxito alcanzado por los distintos países en crear felicidad para un gran número de personas, de un modo análogo a las medidas del éxito en la creación de riqueza, como el PNB. La felicidad se

Uso de fotomultiplicadores de silicio para medidas de alta velocidad y baja intensidad luminosa. Use of silicon photomultipliers for high speed and low and intensity measurements

OpenAIRE

Yebras Rivera, José Manuel

2013-01-01

Esta tesis está dedicada al estudio de los nuevos fotodetectores de alta sensibilidad conocidos como fotomultiplicadores de silicio (SiPMs). Se ha desarrollado una extensa revisión bibliográfica relacionada con estos dispositivos orientada a conocer sus fundamentos, propiedades, dependencias, fenómenos y aplicaciones. Se han realizado medidas experimentales para la caracterización del fotomultiplicador de silicio utilizando para ello fuentes de luz incoherentes. Estos resultados, junto con la...

¿Qué medidas para la mejora de la convivencia se están desarrollando en los centros educativos?: una perspectiva desde dentro

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Alejandra Dobarro González

2013-12-01

Full Text Available El objetivo de este trabajo es analizar qué medidas para la mejora de la convivencia son las que el alumnado percibe que se están desarrollando más en los centros educativos. Para ello se aplicó a una muestra de 2.597 estudiantes de Educación Secundaria Obligatoria del Principado de Asturias una prueba, el Cuestionario M-ESO, con el que se evalúa la opinión del alumnado respecto a aspectos organizativos del centro y del aula relacionados con la convivencia; la resolución de conflictos en el centro; el trabajo y la metodología en el aula; la relación entre los estudiantes; y la relación entre las familias y el centro. Los resultados obtenidos muestran que de las medidas desarrolladas en su centro educativo para la mejora de la convivencia, las estrategias de difusión de normas y sanciones son las que el alumnado percibe como más habituales, seguidas de aquellas que se refieren a la educación en valores y resolución de conflictos. Contrario a lo que sería deseable, las estrategias relativas al consenso de normas son las que el alumnado de ESO percibe como menos habituales en su centro.

Abdominoplastia y pexia de pubis: estandarización de medidas

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O. Ballestas-Campo

2014-06-01

Full Text Available La abdominoplastia es el procedimiento de elección para corregir la flacidez abdominal, la lipodistrofia supra e infraumbilical y la diástasis de los rectos abdominales. Los nuevos métodos añaden liposucción para definir el contorno corporal. Presentamos una estandarización de medidas para lograr una cicatriz abdominal baja y pexia pubiana en casos de lipodistrofias tipo III y IV de Matarasso. Realizamos un estudio observacional, descriptivo y retrospectivo, evaluando las historias clínicas y las fotografías sobre 420 mujeres, con edades entre 18 y 63 años, intervenidas entre 2004 y 2011. Basamos la técnica quirúrgica en los siguientes principios: referencias anatómicas; medidas estandarizadas con la paciente de pie sobre zapatos de tacón alto para el trazado de una incisión suprapúbica baja, siguiendo diseño de los autores; pexia de pubis y región inguinal; cicatriz suprapúbica baja cubierta por un biquini estándar. El 70,95 % de los casos (298 pacientes correspondieron a abdomen grado IV de lipodistrofia, el 28,57 % (120 pacientes al grado III y el 0,47 % (2 pacientes al grado II según Matarasso. Las complicaciones más frecuentes fueron: seroma, (4,04 % , alteraciones cicatríciales (7,37 % , necrosis parcial y epidermolisis (2,38 % y estenosis umbilical (1,19 % . Como conclusión creemos que la estandarización de medidas para el diseño de la cicatriz en la abdominoplastia permite obtener resultados estéticos predecibles y funcionales buenos: cicatriz baja cubierta por un biquini o ropa interior estándar, cicatriz umbilical ovalada, pexia de pubis y excelente definición del contorno abdominal y corporal, con baja tasa de complicaciones.

MEDIDAS DE TRANSMITANCIA ESPECTRAL SIN LA PRESENCIA DE FRANJAS DE INTERFERENCIA: UN MODELO PARA LA OBTENCIÓN DE LAS CONSTANTES ÓPTICAS EN PELÍCULAS DELGADAS SEMICONDUCTORAS

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Heiddy Paola Quiroz Gaitán

Full Text Available En este trabajo presentamos un modelo para la obtención de las constantes ópticas de películas delgadas semiconductoras cuando no es posible observar franjas de interferencia en los espectros. La obtención de las constantes ópticas como el coeficiente de absorción (α, el índice de refracción (n, coeficiente de extinción (k y las propiedades físicas como el ancho de brecha prohibida «Gap» (Eg y el espesor de la película (d, fueron obtenidos para películas delgadas del compuesto Cu2ZnSnSe4 mediante la deconvolución de los espectros experimentales. Para el análisis de las medidas de transmitancia se tomó como base modelo de Bhattacharyya y elementos básicos de la teoría de Sweneapoel. El modelo aquí presentado tiene en cuenta consideraciones de inhomogeneidad en la película y rugosidad en la superficie. Los valores para las constantes ópticas obtenidas por el modelo propuesto presentaron concordancia con los obtenidos para las muestras a partir de la teoría de Sweneapoel, cuando fue posible su aplicación. Una variación del ± 6 % fue observada para los valores del espesor, los cuales fueron corroborados mediante la realización de medidas de perfilometría.

La medida de la inteligencia emocional en el ámbito psicoeducativo

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Iratxe Antonio-Agirre

2017-01-01

Full Text Available La diversidad individual que alberga la escuela representa un reto ineludible. Para promover el desarrollo integral del alumnado resulta necesario favorecer competencias para la vida, como la inteligencia emocional, que les ayuden a lograr un mejor ajuste sociopersonal y escolar. Sin embargo, la diversidad conceptual en torno a la inteligencia emocional ha contribuido a la proliferación de medidas y ha dificultado la integración de la investigación. En todo caso, atendiendo a las propiedades psicométricas y a las dimensiones que miden, este trabajo recoge los principales instrumentos de medida de la inteligencia emocional que posibilitan una evaluación más rigurosa y exhaustiva del constructo en niños, niñas y adolescentes.

Sentidos da trajetória de vida para adolescentes em medida de liberdade assistida

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Clara Costa Gomes

2014-03-01

Full Text Available O presente artigo trata de uma pesquisa que teve como objetivo compreender os sentidos atribuídos por adolescentes que cumpriam medida socioeducativa de liberdade assistida às trajetórias de vida e ao envolvimento com infrações à lei. Foram realizados sete sociodramas semanais com 21 adolescentes da comunidade, dos quais 18 eram do sexo masculino. As informações foram organizadas com base no modelo construtivo-interpretativo de González-Rey e analisadas à luz do aporte teórico da Psicossociologia. Da análise resultaram três zonas de sentido: 1 "Parecia uma vida fácil" - referente à sedução do mundo do crime; 2 "Minhas tábuas de salvação" - sobre as estratégias usadas ante os infortúnios da incursão infracional; 3 "A vida no crime não compensa" - concernente ao saldo das escolhas: dores, perdas e arrependimento. As discussões dos encontros desencadearam nos adolescentes relatos acerca do passado, presente e futuro e reflexões que conduzem à reconstrução de projetos de vida desvinculados de atos de infração. Concluiu-se que os métodos socionômico e de história de vida favoreceram a produção de sentidos pelos adolescentes a partir de sua proposta de ação e reflexão e forneceram informações relevantes para se compreender a trajetória infracional dos adolescentes, constituindo-se em poderosa ferramenta de pesquisa-intervenção junto a adolescentes em cumprimento de medidas socioeducativas.

Estudio comparado entre las medidas de atención lingüística para el alumnado inmigrante en las diferentes comunidades autónomas españolas

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María José ARROYO GONZÁLEZ

2012-01-01

Full Text Available El propósito general de nuestro trabajo es estudiar las diferentes medidas educativas desarrolladas para la atención al alumnado inmigrante, en concreto para la enseñanza de la lengua vehicular en las diferentes comunidades autónomas de nuestro país. Para ello hemos realizado un análisis de contenidos a través de diferentes categorías. El objetivo final es conocer dichos recursos para resaltar las mejores prácticas educativas, poniendo especial énfasis en las ventajas, que a nuestro juicio cada una deellas presentan y analizando también sus inconvenientes.

Abdominoplastia y pexia de pubis: estandarización de medidas

OpenAIRE

O. Ballestas-Campo; A. Pomerane

2014-01-01

La abdominoplastia es el procedimiento de elección para corregir la flacidez abdominal, la lipodistrofia supra e infraumbilical y la diástasis de los rectos abdominales. Los nuevos métodos añaden liposucción para definir el contorno corporal. Presentamos una estandarización de medidas para lograr una cicatriz abdominal baja y pexia pubiana en casos de lipodistrofias tipo III y IV de Matarasso. Realizamos un estudio observacional, descriptivo y retrospectivo, evaluando las historias clínicas y...

Rate amplification of the two photon emission from para-hydrogen toward the neutrino mass measurement

International Nuclear Information System (INIS)

Masuda, Takahiko; Hara, Hideaki; Miyamoto, Yuki; Kuma, Susumu; Nakano, Itsuo; Ohae, Chiaki; Sasao, Noboru; Tanaka, Minoru; Uetake, Satoshi; Yoshimi, Akihiro; Yoshimura, Koji; Yoshimura, Motohiko

2015-01-01

We recently reported an experiment which focused on demonstrating the macro-coherent amplification mechanism. This mechanism, which was proposed for neutrino mass measurements, indicates that a multi-particle emission rate should be amplified by coherence in a suitable medium. Using a para-hydrogen molecule gas target and the adiabatic Raman excitation method, we observed that the two photon emission rate was amplified by a factor of more than 10 15 from the spontaneous emission rate. This paper briefly summarizes the previous experimental result and presents the current status and the future prospect

Rate amplification of the two photon emission from para-hydrogen toward the neutrino mass measurement

Energy Technology Data Exchange (ETDEWEB)

Masuda, Takahiko, E-mail: masuda@okayama-u.ac.jp; Hara, Hideaki; Miyamoto, Yuki [Okayama University, Research Core for Extreme Quantum World (Japan); Kuma, Susumu [Atomic, Molecular and Optical Physics Laboratory, RIKEN (Japan); Nakano, Itsuo [Okayama University, Research Core for Extreme Quantum World (Japan); Ohae, Chiaki [University of Electro-Communications, Department of Engineering Science (Japan); Sasao, Noboru [Okayama University, Research Core for Extreme Quantum World (Japan); Tanaka, Minoru [Osaka University, Department of Physics (Japan); Uetake, Satoshi [Okayama University, Research Center of Quantum Universe (Japan); Yoshimi, Akihiro; Yoshimura, Koji [Okayama University, Research Core for Extreme Quantum World (Japan); Yoshimura, Motohiko [Okayama University, Research Center of Quantum Universe (Japan)

2015-11-15

We recently reported an experiment which focused on demonstrating the macro-coherent amplification mechanism. This mechanism, which was proposed for neutrino mass measurements, indicates that a multi-particle emission rate should be amplified by coherence in a suitable medium. Using a para-hydrogen molecule gas target and the adiabatic Raman excitation method, we observed that the two photon emission rate was amplified by a factor of more than 10{sup 15} from the spontaneous emission rate. This paper briefly summarizes the previous experimental result and presents the current status and the future prospect.

Medidas procesales especiales y proteccíon de los derechos humanos Informe general

NARCIS (Netherlands)

Vervaele, J.A.E.

2009-01-01

El objetivo del informe general es realizar un análisis comparativo de los informes nacionales para evidenciar los procesos de transformación de los sistemas nacionales de justicia penal, en particular del proceso penal, en el que se han introducido medidas procesales especiales para hacer frente al

Medida de la eficiencia ambiental en la industria cerámica española

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Sala Garrido, Ramon

2008-01-01

Full Text Available En el trabajo de Färe, Grosskopf y Hernández-Sancho (2004 se propone un índice de eficiencia medioambiental, para medir el grado en el que las empresas generan outputs deseables al mismo tiempo que reducen su outputs no deseables. Este indicador consiste en una ratio entre una medida para outputs deseables y otra para no deseables. Cada uno de ellos está basado en el uso de las funciones distancia. El índice de los outputs deseables mide el éxito de una empresa k en aumentar estos outputs utilizando el mismo número de inputs y generando el mismo nivel de outputs no deseables. Esta medida de eficiencia medioambiental se ha aplicado a la industria de los pavimentos cerámicos sobre una muestra de empresas a las que se ha aplicado un test de Kruskal-Wallis para determinar la utilidad de este indicador.

Avaliação da reprodutibilidade ultrassonográfica como método para medida da gordura abdominal e visceral Reproducibility of ultrasonography as a method to measure abdominal and visceral fat

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Angélica Lemos Debs Diniz

2009-12-01

Full Text Available OBJETIVO: O objetivo deste estudo é avaliar a variabilidade interobservador do método ultrassonográfico para medida da gordura subcutânea, visceral e perirrenal por meio de técnica padronizada. MATERIAIS E MÉTODOS: Foram avaliados 50 pacientes entre novembro de 2006 e janeiro de 2007. A medida da espessura subcutânea foi realizada com transdutor linear de 7,5 MHz posicionado transversalmente a 1 cm acima da cicatriz umbilical. Para a gordura visceral foi utilizado transdutor de 3,5 MHz posicionado 1 cm acima da cicatriz umbilical, considerando-se a medida entre a face interna do músculo reto abdominal e a parede posterior da aorta na linha média do abdome. A gordura perirrenal foi medida no terço médio do rim direito, com transdutor posicionado na linha axilar média. RESULTADOS: A reprodutibilidade interobservador foi analisada por meio do teste t de Student, com significância de 95%. Não houve diferença significativa entre as médias das medidas das gorduras subcutânea, visceral e perirrenal, com p = 0,7141, 0,7286 e 0,6368, respectivamente. As médias encontradas, com seus respectivos desvios-padrão, foram: 2,64 ± 1,37 para a espessura subcutânea, 6,84 ± 2,38 para a espessura visceral e 4,89 ± 2,6 para a espessura perirrenal. CONCLUSÃO: A ultrassonografia apresentou boa reprodutibilidade interobservador para avaliação da gordura abdominal por meio das medidas das espessuras subcutânea, visceral e perirrenal.OBJECTIVE: The purpose of this study was to evaluate the interobserver variability of ultrasound in the measurement of subcutaneous, visceral and perirenal fat through standard technique. MATERIALS AND METHODS: From November 2006 to January 2007, 50 patients were evaluated. The subcutaneous fat thickness was measured with a 7.5 MHz linear transducer transversely positioned 1 cm above the umbilical scar. For the visceral fat, a 3.5 MHz transducer was also positioned 1 cm above the umbilical scar, considering the

Resistência à mudança na educação superior: design e operacionalização de um instrumento de medida para o MEES

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Angela Cristina Corrêa

2013-04-01

Full Text Available A autonomia científica e tecnológica de um país pressupõe que o mesmo tenha uma educação de qualidade. O objetivo deste artigo é apresentar um instrumento de medida de avaliação da resistência à mudança na administração da educação superior. Propõe-se um desenho e operacionalização para o projeto Mapa Estratégico da Educação Superior (MEES fundamentado em um sistema de gestão integrado. O MEES se constitui em uma proposta metodológica para a operacionalização do Plano de Desenvolvimento Institucional (PDI em Instituições de Ensino Superior (IES. O instrumento de medida de avaliação da resistência à mudança na administração da educação superior (RAMES se fundamenta na seguinte base conceitual: teoria de resposta ao ítem (TRI, teoria psicometrica e no estudo sobre gestão da mudança. A RAMES compõe-se de cinco etapas: 1. elaboração do instrumento de coleta de dados; 2. definição do tamanho amostra representativa da comunidade acadêmica das IES; 3. coleta de dados – conjunto de itens; 4. estimação dos parâmetros dos itens; 5. definição da escala de medida A RAMES tem como expectativa de resultados contribuir para a eficácia na implementação do MEES. Visa também identificar os principais indicadores de resistência a mudança na administração da educação superior.

Resistência à mudança na educação superior: design e operacionalização de um instrumento de medida para o MEES

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Angela Cristina Corrêa

2013-04-01

Full Text Available http://dx.doi.org/10.5007/1983-4535.2013v6n2p55 A autonomia científica e tecnológica de um país pressupõe que o mesmo tenha uma educação de qualidade. O objetivo deste artigo é apresentar um instrumento de medida de avaliação da resistência à mudança na administração da educação superior. Propõe-se um desenho e operacionalização para o projeto Mapa Estratégico da Educação Superior (MEES fundamentado em um sistema de gestão integrado. O MEES se constitui em uma proposta metodológica para a operacionalização do Plano de Desenvolvimento Institucional (PDI em Instituições de Ensino Superior (IES. O instrumento de medida  de avaliação da resistência à mudança na administração da educação superior (RAMES se fundamenta na seguinte base conceitual: teoria de resposta ao ítem (TRI,  teoria psicometrica e no estudo sobre gestão da mudança. A RAMES compõe-se de cinco etapas: 1. elaboração do instrumento de coleta de dados; 2. definição do tamanho amostra representativa da comunidade acadêmica das IES; 3. coleta de dados – conjunto de itens; 4. estimação dos parâmetros dos itens; 5. definição da escala de medida A RAMES tem como expectativa de resultados contribuir para  a eficácia na implementação do MEES. Visa também identificar os principais indicadores de resistência a mudança na administração da educação superior.

As medidas aplicadas aos acordos SPS e TBT sobre as exportações brasileiras de fumo

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Carlos Otávio de Freitas

2015-11-01

Full Text Available O presente estudo tem como objetivo analisar os efeitos das medidas não tarifárias, especificamente as medidas sanitárias e fitossanitárias - SPS e medidas técnicas - TBT, sobre as exportações brasileiras de fumo e se tais efeitos permaneceram nos períodos subsequentes à emissão das notificações. Para tal, foi estimado um modelo gravitacional utilizando uma amostra de 89 países importadores do fumo do Brasil entre o período de 1997 a 2011. O método utilizado na estimação das equações foi o modelo Poisson-Pseudo Maximum Likehood-PPML. Os resultados obtidos mostram que as medidas ou SPS afetaram negativamente o fluxo internacional do comércio de fumo. Além disso, verificou-se que esses efeitos perduraram nos períodos posteriores à emissão da notificação, sendo que as empresas exportadores podem demorar até dois anos para se ajustarem às exigências requeridas. Dentre os objetivos das notificações SPS, a maior parte está relacionada a medidas para proteção da saúde humana e proteção da planta, o que pode explicar a maior dificuldade de adequação, pois são exigências que demandam grandes investimentos. Já as medidas TBT não foram estatisticamente significativas, confirmando o caráter não restritivo dessas notificações sobre o comércio internacional de fumo. Apesar da maior parte das notificações ao fumo estarem associadas a medidas técnicas, os resultados indicaram que elas não configuraram como barreiras ao comércio de fumo. Isso pode sugerir que as exigências a elas referidas, que, em sua grande maioria, foi referente à rotulagem e/ou embalagem, foram atendidas pelo Brasil sem maiores dificuldades. Dessa forma, torna-se importante a inclusão de questões referentes à regulamentação dessas medidas nas discussões e processos de tomada de decisão das empresas exportadoras de fumo. Em termos de ações governamentais, seria interessante a criação ou aperfeiçoamento de políticas no sentido

Equipo comparativo para la medida de conductividad térmica de materiales cerámicos

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Barea, R.

2006-04-01

Full Text Available Among the different techniques available for measuring thermal conductivity, the comparative method (ASTM E1225-99 is the most appropriate for porous materials. This method determines the thermal conductivity in steady state conditions in the 100 - 1300 K temperature range and for conductivities between 0.2 and 200 W/mK, respectively, depending on the equipment characteristics. In the present paper, the design and development, as well as the start up process, of an apparatus based on this method is described. Thermal conductivity data on a mullite based refractory, measured by both the laser flash and the comparative methods, are presented and comparatively discussed in order to validate the developed equipment.

Entre las distintas técnicas de medida de la conductividad térmica de materiales, el método comparativo, recogido en la norma ASTM E1225-99, es el más adecuado para muestras porosas o materiales compuestos. Este método permite determinar conductividades térmicas en estado estacionario, en el intervalo de valores de 0,2 a 200 W/mK, y a temperaturas de ensayo en el rango 100-1300 K, dependiendo del diseño del equipo. En este trabajo se expone el diseño, desarrollo y puesta a punto de un equipo de medida de conductividad térmica basado en este método. Paralelamente, se realiza una validación del equipo mediante el estudio comparativo de los resultados obtenidos usando el equipo comparativo y la técnica del pulso láser en materiales porosos de mullita.

Dispositivo óptico para medida em tempo real da birrefringência de polímeros durante a extrusão

OpenAIRE

Kinglston Soares

2010-01-01

Este projeto teve como principais objetivos o desenvolvimento e aplicação de um dispositivo óptico para medida em tempo real da birrefringência induzida por fluxo durante a extrusão de polímeros. O princípio consiste em medir a intensidade de luz linearmente polarizada transmitida através do polímero sob fluxo e converter este sinal em birrefringência por meio da relação com a diferença de caminho óptico (OPD). O dispositivo óptico foi aferido em bancada com o uso de placas de policarbonato c...

Refração atmosferica nas medidas Doppler

OpenAIRE

Oliveira, Leonardo Castro de

1990-01-01

Orientador: Jose Bittencourt de Andrade Dissertação (mestrado) - Universidade Federal do Parana. Setor de Tecnologia Resumo: Esta dissertação tem por objetivo realizar investigações referentes à refração atmosférica nas medidas Doppler. São considerados quatro modelos para correção troposférica, e o modelo de duas frequências para a correção da refração ionosférica . São também testados de diferentes fontes de dados meteorológicos. Todos os testes são feitos utilizando-se o programa GEO...

Altura do joelho como medida alternativa confiável na avaliação nutricional de idosos

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Vera Elizabeth CLOSS

2015-10-01

Full Text Available Objetivo:Avaliar o uso da altura do joelho como medida alternativa confiável na avaliação nutricional de idosos atendidos em um ambulatório de geriatria.Métodos:Estudo transversal com idosos atendidos em ambulatório de geriatria de um hospital universitário, entre novembro de 2009 e novembro de 2010. Variáveis investigadas: gênero, idade, peso, estatura, altura do joelho, estatura estimada através das equações de Chumlea, índice de massa corporal para as medidas de estatura aferida e estimada e classificado segundo Lipschitz, e dados sociodemográficos. Na análise descritiva dos dados foram usadas medidas de tendência central, dispersão e proporção; a homogeneidade entre as medidas foi verificada através do coeficiente de correlação intraclasse e do gráfico de Bland e Altman e a concordância entre a avaliação nutricional baseada no índice de massa corporal calculado a partir da estatura aferida e a avaliação nutricional baseada no índice de massa corporal calculado a partir da estatura estimada foi avaliada através do coeficiente Kappa ponderado com pesos quadráticos.Resultados:Foram avaliados 186 idosos com média de idade de 74,3±7,1 anos. A média do índice de massa corporal aferido e estimado foi 28,96±5,86 kg/m2e 27,95±5,47 kg/m2, respectivamente, e a prevalência de sobrepeso foi de 59,7% para o índice de massa corporal aferido e 53,2% para o estimado. Foi observada uma boa concordância (Kappa=0,79; p<0,001 entre as duas avaliações.Conclusão:Os resultados mostraram ser possível utilizar a altura do joelho na estimativa da estatura para cálculo do índice de massa corporal em idosos atendidos em ambulatório, alternativa útil para aqueles que apresentam limitações na aferição das medidas, sendo esta uma medida alternativa importante na avaliação nutricional de idosos.

Medidas relativas al acoso escolar y ciberacoso en la normativa autonómica española. Un estudio comparativo

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Fuensanta Cerezo Ramírez

2017-01-01

Full Text Available Sendos informes del Defensor del Pueblo Español alertaron de la necesidad de adoptar medidas para controlar el acoso entre escolares y mejorar la convivencia en las aulas. Sus recomendaciones fueron recogidas por las Comunidades Autónomas (CC.AA. y plasma das en normativas propias. El presente artículo reflexiona sobre las medidas adoptadas, como normas de convivencia, por las administraciones públicas, para los centros educativos sostenidos con fondos públicos. Se plantea un estudio comparativo sobre la no rmativa relacionada con los fenómenos de acoso escolar o bullying y ciberacoso o cyberbullying en ocho CC.AA. seleccionadas al azar. El objetivo principal es conocer cómo se ha abordado esta problemática, así como comparar los protocolos de actuación propu estos y el carácter de las medidas recogidas para su intervención en cada CC.AA. Los resultados indican que la mayoría de las políticas hacen referencia expresa al bullying y una de cada cuatro menciona el cyberbullying, también se detectó que la mitad de los protocolos proponen medidas de actuación ante violencia escolar. En cuanto al carácter de las medidas adoptadas, el análisis demuestra que éstas se dirigen, casi exclusivamente, al alumnado agresor y que, en la mayoría de los casos, son de índole corre ctiva/disciplinaria. Se destaca que en las normativas apenas se hace referencia a medidas de carácter educativo, dejando sin respuesta la propuesta del Defensor del Pueblo que hacía hincapié en las medidas educativas.

Medidas preventivas, correctoras y compensatorias del impacto ecológico de carreteras

OpenAIRE

Aizpurúa Giráldez, Nerea

2011-01-01

Las medidas preventivas, correctoras y compensatorias empleadas en los proyectos de carretera son uno de los elementos clave para conseguir la integración ambiental de estas infraestructuras. De ellas dependerá que los posibles impactos ambientales generados durante su construcción y explotación no supongan un detrimento inadmisible de la calidad ambiental. La tipología de medidas que se vienen aplicando desde hace más de veinte años en durante el proceso de Evaluación de Impacto Ambiental (E...

Metodologias e medidas para a minimização de resíduos em uma indústria moveleira

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Thiara Reis Lopes

2015-05-01

Full Text Available Este estudo foi desenvolvido em uma indústria moveleira localizada no oeste do estado do Paraná, apresenta a aplicação de metodologias para priorização e minimização de resíduos propostas pela epa, sob o enfoque do controle na fonte e reciclagem interna. Foram identificados os resíduos prioritários de acordo com o número de prioridade (N.P., e selecionados os dez primeiros itens para a proposição das medidas entre eles, o efluente resina uréia-formol, o pó e serragem de MDF, os restos de solvente, tintas e pigmentos, os restos de colas e a sucata de latas de alumínio. As alternativas propostas contemplam a aplicação de boas práticas operacionais, o reúso, a reciclagem interna, e a fabricação de novos produtos. Essas proposições pretendem contribuir para melhorias da organização do sistema produtivo e o desempenho industrial, o que possibilita tornar o processo produtivo menos agressivo ao meio ambiente, sob a perspectiva de uma melhoria na imagem da empresa perante aos seus colaboradores e clientes, bem como, valorizar essas atividades que podem propiciar o aumento da lucratividade e reduzir o consumo de recursos naturais.

Neutrino oscillations in dense neutrino gases

International Nuclear Information System (INIS)

Samuel, S.

1993-01-01

We consider oscillations of neutrinos under conditions in which the neutrino density is sufficiently large that neutrino-neutrino interactions cannot be neglected. A formalism is developed to treat this highly nonlinear system. Numerical analysis reveals a rich array of phenomena. In certain gases, a self-induced Mikheyev-Smirnov-Wolfenstein effect occurs in which electron neutrinos are resonantly converted into muon neutrinos. In another relatively low-density gas, an unexpected parametric resonant conversion takes place. Finally, neutrino-neutrino interactions maintain coherence in one system for which a priori one expected decoherence

Validity and reliability of self-reported weight and height measures for the diagnoses of adolescent's nutritional status Validade e confiabilidade das medidas referidas de peso e estatura para o diagnóstico do estado nutricional de adolescents

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Carla Cristina Enes

2009-12-01

Full Text Available PURPOSE: To assess the validity and reliability of self-reported height, weight, and Body Mass Index (BMI to diagnose the nutritional status of adolescents. METHODS: The study included 360 public school students of both genders, with ages ranging from 10 to 15 years. Adolescents self-reported their weight and height, and these values were later obtained directly by interviewers. The validity of BMI based on self-reported measures was calculated using sensitivity and specificity indexes, and positive predictive value (PPV. Agreement between self-reported and measured BMI was evaluated using Kappa's weight coefficient, the Lin correlation coefficient, and Bland-Altman and Lin's plots. RESULTS: Both girls and boys underestimated their weight (-1.0 girls and boys and height (girls - 1.2 and boys - 0.8 (p OBJETIVO: Avaliar a validade do peso, estatura e Índice de Massa Corporal (IMC referidos e sua confiabilidade para o diagnóstico do estado nutricional de adolescentes de Piracicaba. MÉTODOS: Participaram do estudo 360 adolescentes de ambos os sexos, de escolas públicas de Piracicaba, com idade entre 10 e 15 anos. Os adolescentes auto-relataram seu peso e estatura, sendo esses valores obtidos por medidas diretas, logo em seguida, pelos entrevistadores. A validade do IMC referido foi calculada segundo índices de sensibilidade, especificidade e valor preditivo positivo (VPP. Avaliou-se a concordância entre as categorias de IMC obtido por meio das medidas referidas e aferidas a partir do coeficiente kappa ponderado, coeficiente de correlação de Lin. e gráficos de Bland e Altman e Lin. RESULTADOS: Verificou-se que tanto os meninos quanto as meninas subestimaram o peso (-1,0 meninas e meninos e a estatura (meninas -1,2 e meninos -0,8 (p < 0,001. Os valores de IMC aferidos e referidos apresentaram uma concordância moderada. A sensibilidade do IMC referido para classificar os indivíduos obesos foi maior para os meninos (87,5%, enquanto a

Perdón y reconciliación política: dos medidas restaurativas para enfrentar el pasado

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Camila Gamboa-Tapias

2010-03-01

Full Text Available En este artículo defiendo la idea de que lo que nosotros somos como agentes morales y ciudadanos es en parte producto del ambiente social y político en el que crecemos. La comunidad política desempeña un papel preponderante en el desarrollo de nuestra agencia moral y política. Así, no es posible explicar el carácter moral de un individuo en forma separada del contexto social y político en el cual dicho carácter se desarrolla. Cuando las personas viven en regímenes democráticos inclusivos, ellas están mejor equipadas para respetar, en condiciones de igualdad, su valor como personas y ciudadanos. En regímenes opresivos, las personas son más propensas a desarrollar formas defectuosas para tratarse a sí mismos y a los demás. En este artículo discuto dos complejas e importantes nociones: el perdón y la reconciliación política. Las dos nociones aparecen en trabajos teóricos, así como en casos de estudio acerca de procesos de paz y democracias transicionales. Defiendo la idea de que el perdón y la reconciliación política son dos acciones restaurativas para enfrentar el pasado y romper la traumática memoria que pueden causar las ofensas de tipo individual o político. La reconciliación política difiere del perdón en que el primero es una política pública que involucra a toda la comunidad, mientras que el perdón es una medida restaurativa de carácter privado y qué ocurre entre el ofensor y el ofendido. Arguyo que en un régimen democrático inclusivo e igualitario el perdón y la reconciliación deben de respetar el igual valor y dignidad de los seres humanos. Tanto el perdón como la reconciliación política se asemejan en que ambas medidas requieren evaluar el pasado, bien que dicha reflexión implique una ofensa personal o la historia de injusticia de una comunidad política. Esta evaluación del pasado, primero, garantiza el reconocimiento moral o político de la ofensa; segundo, posibilita restaurar y honrar a las

Evaluación de las medidas de eficiencia energética para la estación antártica ecuatoriana Pedro Vicente Maldonado a través del modelo de energía calibrada para edificaciones

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Isabel Miño

2015-08-01

Full Text Available En la Antártica, un continente sensible a las actividades humanas y un lugar estratégico para la investigación de los efectos producidos por el cambio climático, es importante que los proyectos desarrollados ahí minimicen su impacto medioambiental. Bajo este concepto, la estación antártica Pedro Vicente Maldonado, construida en 1990 y operada por Ecuador durante el verano austral, se convertirá dentro de pocos años en una estación permanente. Por ello y con el fin de optimizar el consumo energético, se han analizado diversas medidas de eficiencia energética de acuerdo a un modelo energético basado en el actual consumo de diésel para calefacción. Los resultados de este estudio demuestran que los elementos de la envolvente del edificio, por donde se pierde gran parte de la energía, son el piso y el techo. Por otro lado, debido a la baja relación ventana-paredes de la estación, la reducción en el consumo de diésel generado por el uso de vidrios triple y cuádruple no es significativa. Al combinar diferentes medidas de eficiencia energética, se puede ahorrar hasta un 50% del consumo anual de diésel para calefacción si se compara con el consumo que tendría la estación actual operando en forma permanente. Este estudio servirá de referencia para implementar los cambios necesarios en dicha estación.

Sexualidade na terceira idade: medidas de prevenção para doenças sexualmente transmissíveis e AIDS Sexualidad en la tercera edad: medidas de prevención de enfermedades de transmisión sexual y SIDA Sexuality in the elderly: prevention methods for sexually transmissible illnesses and AIDS

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Manoela Busato Mottin Maschio

2011-09-01

Full Text Available O objetivo deste estudo foi identificar as medidas de prevenção que os idosos estão utilizando para à prevenção das Doenças Sexualmente Transmissíveis e Síndrome da Imunodeficiência Adquirida. A pesquisa foi de caráter prospectivo, quantitativo e descritivo com uma amostragem intencional, realizada com 98 idosos. Foi aplicado um questionário com perguntas abertas e fechadas, relacionadas à vida sexual dos idosos frequentadores de uma instituição que desenvolve programas para a melhoria da qualidade de vida dos idosos no município de Curitiba, Paraná. Dos entrevistados 43%, relatam fazer uso de alguma medida de prevenção. A realização de programas de prevenção voltados para o atendimento de pessoas com 50 anos ou mais, deve estar atenta às questões de sexualidade no envelhecimento. Os idosos devem ser vistos como indivíduos que possuem desejos, necessidades sexuais e que fazem projetos para o futuro.El objetivo de este estudio es identificar medidas que los ancianos están utilizando para la prevención de enfermedades de transmisión sexual y el Enfermedades de Transmisión Sexual Síndrome de Inmunodeficiencia Adquirida. La encuesta fue de carácter prospectivo y cuantitativo con una muestra intencional, realizado con 98 personas de edad avanzada. Se aplicó un cuestionario con preguntas abiertas y cerradas, relacionadas con la vida sexual de los visitantes mayores de una institución que desarrolla programas para la mejora de la calidad de vida de las personas mayores en la ciudad de Curitiba, Paraná, Brasil. De los 43% de los encuestados informaron que usan de alguna medida de prevención. La ejecución de los programas de prevención se centró en la atención de personas mayores de 50 años o más, deben de estar atentos a las cuestiones de la sexualidad en el envejecimiento. Los ancianos deben ser vistos como individuos que tienen necesidades sexuales y deseos, que hacen proyectos para el futuro.This study aimed

La «Escala de Balance Afectivo»: Propiedades psicométricas de un instrumento para la medida del afecto positivo y negativo en población española

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D. Godoy-Izquierdo

2008-01-01

Full Text Available El Balance Afectivo se ha propuesto como uno de los componentes, junto con la Satisfacción Vital, del Bienestar Subjetivo. El Balance Afectivo se refiere a las respuestas emocionales de la persona cuando hace juicios valorativos sobre su vida, y es el resultado de la consideración de las emociones tanto positivas como negativas experimentadas a lo largo de un período de tiempo determinado. Este estudio presenta las características de la Escala de Balance Afectivo (EBA (versión española de la escala de Afecto Positivo y Negativo de Warr et al., 1983 en una muestra española adulta obtenida de la población general. METODOLOGÍA: Participaron voluntariamente en este estudio 219 personas con edades comprendidas entre los 18 y 64 años (M= 30.54; dt= 10.79; 62.1% mujeres procedentes de diferentes contextos comunitarios. Los participantes respondieron 4 medidas sobre balance afectivo, competencia personal inespecífica, salud general y satisfacción vital en una única administración. RESULTADOS: Respecto a las propiedades psicométricas de la EBA, las subescalas de Afecto Positivo y Afecto Negativo muestran una elevada consistencia interna, con valores de alfa de Cronbach de 0.82 y 0.75 respectivamente. Sus elementos muestran un adecuado comportamiento que refleja su pertinencia y relevancia para la medida del Balance Afectivo. La estructura factorial arroja un modelo bifactorial perfectamente ajustado a la propuesta teórica. No obstante, dos ítems necesitarían ser reformulados. El análisis de la posible relación entre el afecto positivo y el afecto negativo realizado utilizando un modelo de ecuaciones estructurales apoya la estrecha relación inversa entre ambas dimensiones de la afectividad. La escala muestra una adecuada validez convergente con medidas de competencia personal inespecífica o global, de salud física y mental y de satisfacción vital. CONCLUSIONES: Los resultados de este estudio nos permiten confirmar la EBA como una

Consecuencias de las medidas no arancelarias impuestas a Colombia por Ecuador y Argentina

OpenAIRE

Perez Giraldo, Johanna Sembelly; Vargas, William

2016-01-01

Con la apertura económica y comercial ha aumentado la negociación de acuerdos comerciales por medio de los cuales los países han logrado tener acceso preferencial libre de aranceles aduaneros. Esta dinámica ha incrementado el uso de medidas no arancelaria como instrumentos para controlar y restringir el acceso a los mercados de los países. Por lo expuesto, esta investigación presenta y analiza las medidas no arancelarias que fueron aplicadas a Colombia por Ecuador y Argentina desde el año 201...

Neutrino masses and neutrino oscillations

CERN Document Server

Di Lella, L

2000-01-01

These lectures review direct measurements of neutrino masses and the status of neutrino oscillation searches using both natural neutrino sources (the Sun and cosmic rays interacting in the Earth atmosphere) and artificial neutrinos (produced by nuclear reactors and accelerators). Finally, future experiments and plans are presented. (68 refs).

Uso de medidas de comorbidades para predição de risco de óbito em pacientes brasileiros hospitalizados Uso de medidas de comorbilidades para predicción de riesgo de óbito en pacientes brasileros hospitalizados Use of comorbidity measures to predict the risk of death in Brazilian in-patients

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Monica Martins

2010-06-01

Full Text Available OBJETIVO: Avaliar o uso de medidas de comorbidade para predizer o risco de óbito em pacientes brasileiros. MÉTODOS: Foram utilizados dados de internações obtidos do Sistema de Informações Hospitalares do Sistema Único de Saúde, que permite o registro de somente um diagnóstico secundário. Foram selecionadas 1.607.697 internações ocorridas no Brasil em 2003 e 2004, cujos diagnósticos principais foram doença isquêmica do coração, insuficiência cardíaca congestiva, doenças cérebro-vasculares e pneumonia. O Índice de Charlson e as comorbidades de Elixhauser foram as medidas de comorbidade utilizadas; o simples registro de algum diagnóstico secundário foi também empregado. A regressão logística foi aplicada para avaliar o impacto das medidas de comorbidade na estimava da chance de óbito. O modelo de base incluiu as seguintes variáveis: idade, sexo e diagnóstico principal. Os modelos de predição de óbitos foram avaliados com base na estatística C e no teste de Hosmer-Lemeshow. RESULTADOS: A taxa de mortalidade hospitalar foi 10,4% e o tempo médio de permanência foi 5,7 dias. A maioria (52% das internações ocorreu em homens e a idade média foi 62,6 anos. Do total de internações, 5,4% apresentava um diagnóstico secundário registrado, mas o odds ratio entre óbito e presença de comorbidade foi de 1,93. O modelo de base apresentou uma capacidade de discriminação (estatística C de 0,685. A melhoria nos modelos atribuída à introdução dos índices de comorbidade foi fraca - equivaleu a zero quando se considerou a estatística C com somente dois dígitos. CONCLUSÕES: Embora a introdução das três medidas de comorbidade nos distintos modelos de predição de óbito tenha melhorado a capacidade preditiva do modelo de base, os valores obtidos ainda são considerados insuficientes. A precisão desse tipo de medida é influenciada pela completitude da fonte de informação. Nesse sentido, o alto sub-registro de

Monitoreo neurointensivo en pediatría (III: Tratamiento. Medidas generales

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Eduardo M. Pleguezuelo Rodríguez

2001-06-01

Full Text Available Se informa que con el neuromonitoreo y el manejo intensivo del traumatismo craneoencefálico grave, se han identificado un grupo de fenómenos fisiopatológicos diferentes, los cuales requieren de medidas disímiles y específicas para cada paciente, lo que hace más racional el tratamiento de ellos. De la misma manera esto ha propiciado que cambien radicalmente las concepciones acerca de antiguos patrones terapéuticos establecidos durante muchos años; ejemplo de esto es el cambio en la reposición hídrica de ellos, los cuales antes se mantenían sobre una vertiente seca y hoy se preconiza la euvolemia estricta, la sustitución de la hiperventilación de rutina por la ventilación optimizada, cambios en la política del uso de agentes osmóticos, la terapia barbitúrica y la craneotomía descompresiva en casos de hipertensión intracraneal refractaria a medidas terapéuticas convencionales. En este trabajo se hace una revisión actualizada de las principales medidas terapéuticas utilizadas en estos pacientes, acorde con lo que plantean los lineamientos para el tratamiento del traumatismo craneal grave de la Asociación Americana de Cirujanos Neurológicos y los del consorcio europeo para la lesión cerebral. Las medidas terapéuticas utilizadas en estos pacientes se dividen en 2 fases. En este tercer trabajo de actualización se aborda el manejo de la primera fase que corresponde a la estabilización urgente inicial antes de establecer la medición de la presión intracraneal (PIC, así como las medidas generales de la segunda fase una vez iniciado el monitoreo de la PIC. Principios terapéuticos que desde hace algunos años se vienen utilizando en el Hospital provincial General y el Hospital Pediátrico Provincial Docente de Camagüey para el manejo del trauma craneal grave, los cuales se basan en medidas iniciales en la recepción, acorde con lo que plantean los principios del soporte vital avanzado en trauma para la reanimaci

Medidas dinámicas de predictibilidad en el índice s&p 500 y sus determinantes

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Javier Humberto Ospina Holguín

2015-04-01

Full Text Available El objeto de este estudio es medir la predictibilidad del índice accionario estadounidense S&P 500 y establecer posibles determinantes de esta predictibilidad. La predictibilidad se ha estudiado ampliamente, pero en pocos casos mediante medidas dinámicas y per se, como se hace aquí. Para establecer la predictibilidad se utilizan la medida eta del campo de las redes neuronales, el valor p del test de la razón de varianzas del campo de la econometría financiera y el análisis de fluctuación sin tendencia del campo de la econofísica. Se construye un algoritmo de inversión basado en las medidas dinámicas de predictibilidad que es mejor que la estrategia de comprar y mantenerse en el periodo estudiado. Para la medida más promisoria, se establece una relación empírica entre la predictibilidad y varios factores económicos y financieros. El panorama que arroja este estudio es el de un mercado que no es estáticamente predecible, sino cuya predictibilidad evoluciona dinámicamente en el tiempo, lo cual es compatible con la hipótesis del mercado adaptativo.

Avaliação de bolsas de produtividade em pesquisa do CNPq e medidas bibliométricas: correlações para todas as grandes áreas

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Jacques Wainer

Full Text Available Este trabalho estuda as correlações entre decisões tomadas no fim de 2009, sobre renovação ou não de bolsas de produtividade em pesquisa do CNPq e medidas bibliométricas. Para cada nível da bolsa e para cada subárea, calculamos a correlação da decisão em subir o pesquisador de nível, mantê-lo no nível original ou rebaixá-lo, com várias medidas bibliométricas, como produção total (artigos, conferências, livros e capítulos de livros, produção nos últimos 5 anos, produção indexada no Web of Science, citações recebidas por artigo, citações recebidas por artigo escrito nos últimos 5 anos, índice H, etc. Os dados de citações foram extraídos tanto do Google Scholar como do Web of Science. As correlações de cada subárea são agrupadas em cada uma das 8 grandes áreas do CNPq (Ciências Agrícolas, Ciências Biológicas, Ciências Exatas, Ciências Humanas, Ciências da Saúde, Ciências Sociais, Engenharia e Artes. Indicamos quais são as métricas bibliométricas com maior correlação, com as decisões do CNPq para cada nível e para cada uma das grandes áreas. Discutimos algumas grandes áreas nas quais parece haver uma maior coerência, através dos vários níveis da bolsa entre as métricas mais correlacionadas com as decisões.

Comparação e correlação entre automedida, medida casual e monitorização ambulatorial da pressão arterial

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Weimar Kunz Sebba Barroso de Souza

2011-08-01

Full Text Available FUNDAMENTO: A medida casual da pressão arterial (PA pelos profissionais de saúde está sujeita a uma grande variabilidade, sendo necessário buscar novos métodos que possam superar essa limitação. OBJETIVO: Comparar e avaliar a correlação entre os níveis de PA obtidos por meio da automedida da pressão arterial (AMPA com a medida casual e com a monitorização ambulatorial da pressão arterial (MAPA. MÉTODOS: Avaliamos hipertensos que realizaram as três metodologias de medida da PA com intervalo menor que 30 dias; as médias das pressões foram utilizadas para comparação e correlação. Foram empregados os aparelhos: OMRON 705 CP (medida casual, OMRON HEM 714 (AMPA e SPACELABS 9002 (MAPA. RESULTADOS: Foram avaliados 32 pacientes, 50,09% mulheres, idade média 59,7 (± 11,2 anos, média do IMC 26,04 (± 3,3 kg/m². Valores médios de pressão sistólica (PAS e pressão diastólica (PAD para a AMPA foram de 134 (± 15,71mmHg e 79,32 (± 12,38 mmHg. Na medida casual as médias da PAS e PAD foram, respectivamente, 140,84 (± 16,15mmHg e 85 (± 9,68 mmHg. Os valores médios da MAPA na vigília foram 130,47 (± 13,26 mmHg e 79,84 (± 9,82 mmHg para PAS e PAD, respectivamente. Na análise comparativa, a AMPA apresentou valores semelhantes aos da MAPA (p > 0,05 e diferentes da medida casual (p < 0,05. Na análise de correlação a AMPA foi superior à medida casual, considerando a MAPA como o padrão de referência nas medidas tensionais. CONCLUSÃO: A AMPA apresentou melhor comparação com a MAPA do que a medida casual e também se correlacionou melhor com a aquela, especialmente para a pressão diastólica, devendo ser considerada uma alternativa com baixo custo para o acompanhamento do paciente hipertenso.

Anti-neutrino imprint in solar neutrino flare

Science.gov (United States)

Fargion, D.

2006-10-01

A future neutrino detector at megaton mass might enlarge the neutrino telescope thresholds revealing cosmic supernova background and largest solar flares (SFs) neutrinos. Indeed the solar energetic (Ep>100 MeV) flare particles (protons, α), while scattering among themselves on solar corona atmosphere must produce prompt charged pions, whose chain decays are source of a solar (electron muon) neutrino 'flare' (at tens or hundreds MeV energy). These brief (minutes) neutrino 'bursts' at largest flare peak may overcome by three to five orders of magnitude the steady atmospheric neutrino noise on the Earth, possibly leading to their detection above detection thresholds (in a full mixed three flavour state). Moreover the birth of anti-neutrinos at a few tens of MeV very clearly flares above a null thermal 'hep' anti-neutrino solar background and also above a tiny supernova relic and atmospheric noise. The largest prompt solar anti-neutrino 'burst' may be well detected in future Super Kamikande (gadolinium implemented) anti-neutrino \\bar\

Método del “Pulso Láser” para la medida de la difusividad térmica en materiales cerámicos

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García, E.

2001-08-01

Full Text Available Among the several techniques available to measure the thermal conductivity/ diffusivity, the laser flash method stands out for its low run time (less than 1 hour per temperature and the reduced sample size required. Nevertheless, the laser flash technique is not very accurate for porous materials due to laser transmission problems and the underestimation of the total sample thickness. The attaching to the porous sample of two thin foils of an opaque and high diffusivity material (Cu can solve these problems. This type of assembly was used to measure diffusivity in a porous alumina material. Data obtained are compared with theoretical models, wich predict effective thermal conductivity of the porous material from the thermal conductivity of the dense material, the amount of porosity and the type of microstructure.

Entre las distintas técnicas de medida de la conductividad/difusividad térmica de materiales, destaca la técnica del pulso láser por la rapidez de medida de la difusividad térmica y la facilidad de preparación de las muestras. Sin embargo, cuando se mide la difusividad térmica en materiales porosos, aparecen problemas relacionados con la transmisión del haz láser y la subestimacion del espesor de la muestra. En este trabajo, se propone un método para evitar estos problemas que consiste en formar un sistema tricapa Cu/material poroso/Cu. Este método se ha verificado experimentalmente utilizando materiales de alúmina densa y porosa. Los valores experimentales para la alúmina porosa se han explicado a partir de modelos que estiman la conductividad térmica efectiva de un material poroso en función de la conductividad del material denso, la porosidad y el tipo de microestructura.

Diseño de un método para controlar la combustión en un motor 2T de gasolina basado en la medida del régimen instantáneo

OpenAIRE

PÉREZ PÉREZ, JUAN CARLOS

2016-01-01

[ES] En determinadas condiciones de operación los motores de 2T de gasolina operan con autoencendido de la mezcla, lo cual hace perder el control tradicional a través de la bujía. En esos casos es preciso conocer cuándo está teniendo lugar ese autoencendido, para así determinar si es necesario llevar a cabo alguna acción correctora para controlar que éste tenga lugar en el momento adecuado. El alumno explorará la posibilidad de utilizar la medida del régimen instantáneo del motor para consegu...

Medida de la eficiencia en entidades no lucrativas: un estudio empírico para fundaciones asistenciales

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Carmen M. Martínez Franco

2014-06-01

Full Text Available La medida del rendimiento de cualquier unidad de decisión es un objetivo ciertamente deseable para conocer si la aplicación de sus recursos económicos (inputs es adecuada en cada momento para conseguir su objetivo productivo. En este sentido, las entidades sin fines lucrativos no son ajenas a esta necesidad de gestión, presentando dificultades a˜nadidas la medida de su desempe˜no, dado que por su carácter de «no lucrativas» su objetivo último no es la maximización de beneficio, sino la consecución de fines de carácter social, en ocasiones difícilmente cuantificables. En el contexto descrito, el presente trabajo evalúa, dentro del sector de las entidades sin fines lucrativos, el rendimiento de las fundaciones estatales de tipo asistencial radicadas en Espa˜na, mediante la aplicación de la técnica no paramétrica del análisis envolvente de datos (DEA, capaz de determinar la frontera de «buenas prácticas» de las unidades evaluadas a partir de un modelo de optimización matemática, al tiempo que permite estudiar las variaciones del cambio productivo a través del cálculo del índice de productividad total de los factores de Malmquist basado en la metodología DEA mencionada. El estudio se complementa con un análisis DEA en 2 etapas aplicando un modelo de regresión logit para evaluar la posible asociación de covariables de relevancia en el sector de las fundaciones, tales como su tamaño, liquidez, endeudamiento y antigüedad, con el rendimiento de dichas organizaciones previamente calculado. Measuring the performance of any unit decision is certainly desirable in order to discover whether the application of economic resources (inputs is appropriate at all times to achieve its central objective. In this sense, non-profit organizations are not immune to this need for management, having additional difficulties in their performance, since because of their «non-profit» character their ultimate goal is not to maximize profit

Collective neutrino oscillations and neutrino wave packets

Energy Technology Data Exchange (ETDEWEB)

Akhmedov, Evgeny; Lindner, Manfred [Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg (Germany); Kopp, Joachim, E-mail: akhmedov@mpi-hd.mpg.de, E-mail: jkopp@uni-mainz.de, E-mail: lindner@mpi-hd.mpg.de [PRISMA Cluster of Excellence and Mainz Institute for Theoretical Physics, Johannes Gutenberg University, 55099 Mainz (Germany)

2017-09-01

Effects of decoherence by wave packet separation on collective neutrino oscillations in dense neutrino gases are considered. We estimate the length of the wave packets of neutrinos produced in core collapse supernovae and the expected neutrino coherence length, and then proceed to consider the decoherence effects within the density matrix formalism of neutrino flavour transitions. First, we demonstrate that for neutrino oscillations in vacuum the decoherence effects are described by a damping term in the equation of motion of the density matrix of a neutrino as a whole (as contrasted to that of the fixed-momentum components of the neutrino density matrix). Next, we consider neutrino oscillations in ordinary matter and dense neutrino backgrounds, both in the adiabatic and non-adiabatic regimes. In the latter case we study two specific models of adiabaticity violation—one with short-term and another with extended non-adiabaticity. It is demonstrated that, while in the adiabatic case a damping term is present in the equation of motion of the neutrino density matrix (just like in the vacuum oscillation case), no such term in general appears in the non-adiabatic regime.

Abuso de las medidas y medidas abusivas. Crítica al pensamiento bibliométrico hegemónico

OpenAIRE

GÒMEZ-MORALES, YURI JACK

2018-01-01

RESUMEN En este ensayo reflexivo se hace una crítica a la economía política de la medición de la ciencia, la cual se ejemplifica mediante el análisis del factor de impacto como medida de la calidad científica; se explican los mecanismos sociales y culturales que operan en la construcción de estas formas de pensar y actuar hegemónicas; y se advierte sobre las graves consecuencias de este proyecto global para la desinstitucionalización de la ciencia local, y el surgimiento de una ciencia nacion...

Detecting supernova neutrinos in Daya Bay Neutrino Laboratory

International Nuclear Information System (INIS)

Huang Mingyang; Guo Xinheng; Yang Binglin

2011-01-01

While detecting supernova neutrinos in the Daya Bay neutrino laboratory, several supernova neutrino effects need to be considered, including the supernova shock effects, the neutrino collective effects, the Mikheyev-Smirnov-Wolfenstein (MSW) effects, and the Earth matter effects. The phenomena of neutrino oscillation is affected by the above effects. Using some ratios of the event numbers of different supernova neutrinos, we propose some possible methods to identify the mass hierarchy and acquire information about the neutrino mixing angle θ13 and neutrino masses. (authors)

PROPRIEDADES PSICOMÉTRICAS DE INSTRUMENTOS DE MEDIDAS: BASES CONCEITUAIS E MÉTODOS DE AVALIAÇÃO–PARTE I

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Maria Elena Echevarría-Guanilo

2017-01-01

Full Text Available Objetivo: presentar y discutir bases conceptuales y métodos de evaluaciones que fundamentan importantes propiedades de instrumentos de medidas. En esta primera parte, se presentan y discute los conceptos de confiabilidad, responsividad e interpretabilidad, citados ejemplos de las principales formas de evaluación de esas propiedades. Método: estudio teórico basado en la literatura internacional y nacional y en los instrumentos Consensus-based Standards for the selection of health Measurement Instruments y Evaluating the Measurement of Patient-Reported Outcomes que contemplan conceptos de evaluación de instrumentos para la evaluación de los resultados de los pacientes. Resultados: en este enfoque, se puede percibir que todavía hay divergencias en algunas descripciones conceptuales. Sin embargo, los autores resaltan la importancia de la confiabilidad para evaluar el instrumento de medida. Se destaca la importancia del conocimiento del Modelo Conceptual, de las propiedades de medidas y de los diferentes métodos de evaluación para garantizar, principalmente en estudio de validación de instrumentos, resultados confiables y válidos. Conclusiones : se concluye que la discusión presentada sobre la confiabilidad, responsividad e interpretabilidad contribuye a los profesionales de la salud en el conocimiento teórico y sentido crítico en la elección de instrumentos y en la conducción de análisis sobre esas propiedades de medida.

Aproximación de reclamos contingentes para la predicción de riesgo de crédito en sus medidas de determinación de la distancia de default y su probabilidad de quiebra para colombia1,2

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Juan Sergio Cruz Merchán

2011-01-01

Full Text Available El propósito de este artículo es evaluar el grado de aplicabilidad de la ruptura -Black y Scholes (1973 y Merton (1974- en el mercado de valores de Colombia, desde la aproximación de reclamos contingentes, dentro de la nueva coyuntura del ciclo económico para América Latina. En particular, se examinará la habilidad de la Aproximación de Reclamos Contingentes desde la perspectiva de KMV Moody's, para estimar dos indicadores de riesgo de crédito: la distancia de bancarrota y la probabilidad de default, y luego comparar estas medidas con las que produce el mercado. Los resultados sugieren la posibilidad de uso de este modelo en Colombia, en especial para las empresas que no cotizan en bolsa.

Análise de desempenho de medidas estruturais e não estruturais de controle de inundações em uma bacia urbana

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Thiago Galvão Tiradentes Decina

2016-03-01

Full Text Available RESUMO Este trabalho teve como objetivo analisar, por meio de simulações hidrológicas e hidráulicas, o desempenho de algumas medidas de controle de inundação, estruturais e não estruturais. Para tanto, os mapas e demais informações espaciais da bacia hidrográfica do Córrego do Gregório, em São Carlos (SP, foram digitalizadas com auxílio do software de geoprocessamento ArcGIS(r e imagens de satélite de alta resolução. Com base nessas informações, foram propostos cenários alternativos que incorporaram as medidas de controle. Através da utilização dos softwares HEC-HMS e HEC-RAS realizaram-se as modelações hidráulicas e hidrológicas, utilizando tempos de retorno de 25, 50 e 100 anos para a chuva de projeto. Com os resultados obtidos (hidrogramas de cheia e manchas de inundação referentes a cada tempo de retorno, foi possível analisar as medidas, comparando-se os diferentes cenários. Concluiu-se, para este caso, que os melhores resultados correspondem à associação das medidas estruturais e não estruturais. Contudo, também foi verificado que, mesmo com a concretização do cenário mais favorável, o problema das inundações não seria satisfatoriamente equacionado, o que revela a necessidade de se considerar outras medidas para minimizar os prejuízos decorrentes das inundações, tais como medidas de controle na fonte, seguros contra inundações e sistemas de alerta antecipados.

Neutrinos

CERN Multimedia

CERN. Geneva

2004-01-01

The Standard Model predicts that the neutrinos are massless and do not mix. Generic extensions of the Standard Model predict that neutrinos are massive (but, very likely, much lighter than the charged fermions). Therefore, the search for neutrino masses and mixing tests the Standard Model and probes new phasics. Measurements of various features of the fluxes of atmospheric, solar and, more recently, reactor neutrinos have provided evidence for neutrino oscillations and therefore for neutrino masses and mixing. These results have significant theoretical implications: new physics exists, and its scale can be estimated. There are interesting lessons for grand unified theories and for models of extra dimensions. The measured neutrino flavor parameters pose a challenge to flavor models.

Neutrino problems proliferate (Neutrino 94 conference report)

International Nuclear Information System (INIS)

Gordon, Fraser

1994-01-01

The enigma of the neutrino continues. More than sixty years after its hesitant prediction by Pauli and forty years after its discovery by Reines and Cowan, the neutrino still refuses to give up all its secrets. The longer we travel down the neutrino road and the more we find out about these particles, the more problems we uncover en route. The present state of the neutrino mystery was highlighted at the Neutrino 94 meeting in Eilat, Israel, from 29 May to 3 June. It was a distinguished meeting, with the first morning including one session chaired by neutrino co-discoverer Fred Reines, and an introductory talk by muon-neutrino co-discoverer Leon Lederman. One figurehead neutrino personality conspicuously absent this time was Bruno Pontecorvo, who died last year and had attended the previous conference in the series, in Grenada, Spain, in 1992

Neutrino problems proliferate (Neutrino 94 conference report)

Energy Technology Data Exchange (ETDEWEB)

Gordon, Fraser

1994-09-15

The enigma of the neutrino continues. More than sixty years after its hesitant prediction by Pauli and forty years after its discovery by Reines and Cowan, the neutrino still refuses to give up all its secrets. The longer we travel down the neutrino road and the more we find out about these particles, the more problems we uncover en route. The present state of the neutrino mystery was highlighted at the Neutrino 94 meeting in Eilat, Israel, from 29 May to 3 June. It was a distinguished meeting, with the first morning including one session chaired by neutrino co-discoverer Fred Reines, and an introductory talk by muon-neutrino co-discoverer Leon Lederman. One figurehead neutrino personality conspicuously absent this time was Bruno Pontecorvo, who died last year and had attended the previous conference in the series, in Grenada, Spain, in 1992.

Una medida de eficiencia de mercado. Un enfoque de teoría de la información

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Reyna Susana García Ruiz

2014-01-01

Full Text Available En este trabajo, con base en el concepto de entropía de Shan-non, se propone una medida de eficiencia de mercado que uti-liza la función de densidad empírica de los rendimientos comoalfabeto para calcular la entropía del sistema y proveer con ellouna medida de eficiencia de mercado. Se demuestra que bajociertas condiciones de ergodicidad y de estacionariedad la en-tropía muestral converge a la entropía del estado dominante,lo que valida el uso de la entropía muestral como medida deeficiencia del sistema. Asimismo, se demuestra que la medidapropuesta es consistente con algunos de los axiomas de Artz-neret al.(1999 acerca de una medida coherente de riesgo. Porúltimo, con fines ilustrativos, se llevan a cabo varias aplicacio-nes de la medida de eficiencia propuesta a distintos mercadosde capitales: DJIA, S&P500, FTSE100 e IPC.

Fundamentos e métodos de medidas de energia dinâmica no SPT

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Antonio Belincanta

2000-05-01

Full Text Available Discutem-se neste trabalho os métodos disponíveis no Brasil e no exterior para a medida da energia transferida às hastes no SPT, apresentando-se inclusive registros típicos dos eventos dinâmicos correspondentes

Physics of neutrino flavor transformation through matter-neutrino resonances

Science.gov (United States)

Wu, Meng-Ru; Duan, Huaiyu; Qian, Yong-Zhong

2016-01-01

In astrophysical environments such as core-collapse supernovae and neutron star-neutron star or neutron star-black hole mergers where dense neutrino media are present, matter-neutrino resonances (MNRs) can occur when the neutrino propagation potentials due to neutrino-electron and neutrino-neutrino forward scattering nearly cancel each other. We show that neutrino flavor transformation through MNRs can be explained by multiple adiabatic solutions similar to the Mikheyev-Smirnov-Wolfenstein mechanism. We find that for the normal neutrino mass hierarchy, neutrino flavor evolution through MNRs can be sensitive to the shape of neutrino spectra and the adiabaticity of the system, but such sensitivity is absent for the inverted hierarchy.

Neutrino Physics

CERN Multimedia

CERN. Geneva; Dydak, Friedrich

2001-01-01

Starting from a review of theoretical concepts and experimental results in the early years of neutrino physics after Pauli's 1930 letter, today's double role of the neutrino as a cornerstone of the Standard Model and as a promising probe of physics beyond the Standard Model will be discussed. Topics comprise: - Conventional neutrino beams - Neutrinos as probes of the nucleon structure - Neutrinos from the universe - Dirac or Majorana neutrinos - Neutrino oscillations - MNS matrix - CP violation in the lepton sector - Neutrino factory.

Neutrino Physics

CERN Multimedia

CERN. Geneva. Audiovisual Unit

2002-01-01

Starting from a review of theoretical concepts and experimental results in the early years of neutrino physics after Pauli's 1930 letter, today's double role of the neutrino as a cornerstone of the Standard Model and as a promising probe of physics beyond the Standard Model will be discussed. Topics comprise: - Conventional neutrino beams - Neutrinos as probes of the nucleon structure - Neutrinos from the universe - Dirac or Majorana neutrinos - Neutrino oscillations - MNS matrix - CP violation in the lepton sector - Neutrino factory.

Medida de Segurança: a violação do direito à saúde a partir do conceito de periculosidade

OpenAIRE

Valéria Rondon Rossi

2015-01-01

A relação dos fenômenos da loucura e criminalidade foi um ponto estratégico para a constituição da medicina mental – psiquiatria e para a constituição de instituições de controle, punição e regeneração. No Brasil, a resposta penal aos crimes dos loucos infratores é a medida de segurança, instituto que se anuncia como despenalizante e voltado ao tratamento em saúde. No entanto, vigora o sistema da periculosidade como parâmetro para imposição e suspensão da medida de segurança, o que faz com qu...

Obtenção de medidas de imagens adquiridas em estereomiscroscópio e escaner de mesa = Measures obtained from images acquired by a stereomicroscope and a desktop scanner

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Larentis, Naiara Leites

2014-01-01

Full Text Available Objetivo: Esse estudo teve por objetivo comparar medidas obtidas de imagens de secções dentárias adquiridas em estereomiscrópio e escâner de mesa, assim como determinar se existem diferenças entre os dois métodos. Métodos: Cinquenta dentes humanos extraídos foram seccionados no sentido mésio-distal. Cada secção foi fotografada em estereomicroscópio e digitalizada em escâner de mesa com resolução de 230 dpi. O programa Photoshop foi utilizado para obter medidas verticais e horizontais das imagens de cada secção dentárias, adquiridas por ambos os métodos. Foram repetidas as medidas em 20% das amostras, selecionadas randomicamente. Resultados: As medidas iniciais e as repetidas apresentaram correlação positiva e o teste t para amostras pareadas não revelou diferença significativa (a=5% entre elas. A média das medidas e os devios-padrão foram: horizontal, estereomicroscópio 8,89 mm±4,30 mm e escâner 8,89 mm±4,52 mm; vertical, estereomicroscópio 4,42 mm±2,19 mm e escâner 4,43 mm±2,19 mm. Os resultados do teste t para amostras pareadas (a=5% não mostrou nenhuma diferença significativa entre os dois métodos para as medidas horizontais (p=0,685 e verticais (p=0,299. Conclusão: O escâner de mesa pode ser usado substituindo o estereomicroscópio na aquisição de imagens de secções dentárias para a obtenção de medidas verticais e horizontais

Medidas tipográficas: un recuento

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Oriol Moret Viñals

2015-07-01

Full Text Available Breve repaso al desarrollo de la concepción métrica en la tipografía en plomo, alternativa y complemento de la visión habitual en lo que conocemos como “tipometría”. Se parte de una noción amplia de medida: el factor cuantitativo se dilata con la articulación de relaciones proporcionales e integra la dimensión cualitativa de los sistemas métricos tradicionales. La tipografía se considera bajo presupuestos similares: como sistema articulado de piezas materiales cuyas magnitudes contienen usos y valores específicos, más allá de su simple expresión numérica. Con tales premisas, se revisan fuentes documentales significativas del “período de la imprenta manual”. Su examen, vinculado a los usos y costumbres de oficio, desvela la distinta aproximación métrica, que puede resumirse en tres fases evolutivas: hermética, intensiva, expansiva –como recogen las referencias de los cuerpos tipográficos: adjetivas, sustantivas, numéricas. Se proporciona así un marco para apreciar el cambio de sentido en las medidas tipográficas hasta nuestros días.

Aplicaciones de los modelos multinivel al análisis de medidas repetidas en estudios longitudinales

OpenAIRE

María Victoria Zunzunegui; María Jesús García de Yébenes; Mathieu Forster; María Dolores Aguilar Conesa; Angel Rodríguez Laso; Ángel Otero

2004-01-01

Este trabajo es una introducción al análisis de medidas repetidas en estudios longitudinales. Se utiliza un marco analítico con dos etapas, ajustando modelos jerárquicos lineales con dos niveles. El primer nivel corresponde a la ocasión (tiempo) de medida y el segundo al individuo. Estos modelos estadísticos proceden de las ciencias sociales, en las que se han utilizado durante más de 25 años para analizar datos en organizaciones con múltiples niveles. Su aplicación permi...

Neutrino mixing and future accelerator neutrino experiments

International Nuclear Information System (INIS)

Bilenky, S.M.

1992-01-01

No evidence for neutrino mixing has been obtained in experiments searching for oscillations with neutrinos from accelerators and reactors. The possible reason is that neutrino masses are too small to produce any sizable effects in the experiments with terrestrial neutrinos. We put forward here the point of view that the reason for that can be traced to the presence of a hierarchy of neutrino masses as well as strength of couplings between lepton families. (orig.)

Acquiring information about neutrino parameters by detecting supernova neutrinos

Science.gov (United States)

Huang, Ming-Yang; Guo, Xin-Heng; Young, Bing-Lin

2010-08-01

We consider the supernova shock effects, the Mikheyev-Smirnov-Wolfenstein effects, the collective effects, and the Earth matter effects in the detection of type II supernova neutrinos on the Earth. It is found that the event number of supernova neutrinos depends on the neutrino mass hierarchy, the neutrino mixing angle θ13, and neutrino masses. Therefore, we propose possible methods to identify the mass hierarchy and acquire information about θ13 and neutrino masses by detecting supernova neutrinos. We apply these methods to some current neutrino experiments.

Neutrino cosmology

International Nuclear Information System (INIS)

Berstein, J.

1984-01-01

These lectures offer a self-contained review of the role of neutrinos in cosmology. The first part deals with the question 'What is a neutrino.' and describes in a historical context the theoretical ideas and experimental discoveries related to the different types of neutrinos and their properties. The basic differences between the Dirac neutrino and the Majorana neutrino are pointed out and the evidence for different neutrino 'flavours', neutrino mass, and neutrino oscillations is discussed. The second part summarizes current views on cosmology, particularly as they are affected by recent theoretical and experimental advances in high-energy particle physics. Finally, the close relationship between neutrino physics and cosmology is brought out in more detail, to show how cosmological constraints can limit the various theoretical possibilities for neutrinos and, more particularly, how increasing knowledge of neutrino properties can contribute to our understanding of the origin, history, and future of the Universe. The level is that of the beginning graduate student. (orig.)

Neutrino factories

International Nuclear Information System (INIS)

Dydak, F.

2002-01-01

The discovery of neutrino oscillations marks a major milestone in the history of neutrino physics, and opens a window to what lies beyond the Standard Model. Many current and forthcoming experiments will answer open questions; however, a major step forward, up to and possibly including CP violation in the neutrino mixing matrix, will be offered by the neutrino beams from a neutrino factory. The neutrino factory is a new concept for producing neutrino beams of unprecedented quality in terms of intensity, flavour composition, and precision of the beam parameters. These beams enable the exploration of otherwise inaccessible domains in neutrino oscillation physics by exploiting baselines of planetary dimensions. Suitable detectors pose formidable challenges but seem within reach with only moderate extrapolations from existing technologies. Although the main physics attraction of the neutrino factory is in the area of neutrino oscillations, an interesting spectrum of further opportunities ranging from high-precision, high-rate neutrino scattering to physics with high-intensity stopped muons comes with it

Implementación de medidas de bioseguridad en granjas de broilers para reducir la prevalencia de Campylobacter: cuestiones prácticas, problemas y soluciones

OpenAIRE

Cerda-Cuellar, M.; Laureano, L.; Corujo, A.; Fernandez, A.; Vidal, E.; Hald, Birthe; Dolz, R.

2014-01-01

Actualmente, la implementación y mejora de las medidas de bioseguridad en granjas de broilers a nivel de nave es la una de las principales herramientas disponibles para el control de Campylobacter en el primer eslabón de la cadena alimentaria. Una de las principales actuaciones a acometer implica la instalación de una barrera higiénica en la antesala, así como un entrenamiento del ganadero, quien va a tener que cambiar sus hábitos de trabajo. Hay que tener en cuenta que la principal vía de tr...

Normatização de medidas acústicas da voz normal

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Araújo Simone Adad

2002-01-01

Full Text Available Introdução: A análise acústica da voz com o avanço da tecnologia digital surge como um exame complementar promissor para aumentar a precisão diagnóstica em laringologia. Objetivo: Normatização das medidas acústicas de freqüência fundamental, perturbação e ruído na voz normal de brasileiros dos sexos masculino e feminino. Forma de estudo: Clínico prospectivo. Material e Método: Pesquisa no período de março a agosto de 1997, no Ambulatório de Otorrinolaringologia do Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo, com 80 voluntários da cidade de Ribeirão Preto e região, sendo 40 do sexo masculino e 40 do feminino, selecionados por meio de triagem, foram realizadas gravações digitais dos fonemas /a/, /e/ e /i/, originando uma amostra de 240 sinais acústicos submetidos ao Programa de Análise Acústica da Voz, desenvolvido na Escola de Engenharia de São Carlos da Universidade de São Paulo com obtenção das medidas acústicas. Resultados: Foram obtidos valores médios em relação a sexo e fonemas das medidas de: Freqüência fundamental, Jitter (Directional Perturbation Factor, Perturbation Variation Index, Jitter Ratio, Jitter Factor, Period Perturbation Quotient, Shimmer (Directional Perturbation Factor, Amplitude Variation Index, Amplitude Perturbation Quotient, Spectral Noise Level, Harmonic-to-noise ratio, Harmonic-to-noise ratio cepstrum, Normalized Noise Energy e Breathiness ratio. Conclusão: A normatização das medidas acústicas é necessária para conhecer melhor a voz normal. Os valores obtidos são compatíveis em sua grande maioria com à literatura existente.

Adolescente em conflito com a lei e medidas socioeducativas: limites e (impossibilidades

Directory of Open Access Journals (Sweden)

Francischini, Rosângela

2005-01-01

Full Text Available Reinserção social, readaptação, ajustamento social, integração à família e sociedade. Várias são as expressões empregadas para referir-se ao efeito desejado do trabalho com o jovem em conflito com a lei, em cumprimento de medidas socioeducativas, particularmente em privação de liberdade. Parte do aparato legal do Estado, a partir da promulgação do Estatuto da Criança e do Adolescente, significaram, essas medidas, uma chamada à responsabilização do jovens, em face da transgressão cometida. No entanto, avalia-se, o que dá a essas medidas o caráter socioeducativo, fazendo com que o trabalho desenvolvido nas instituições diferencie-se do cumprimento de pena? Estrutura física, formação de recursos humanos, ações educativas e trabalho transdiciplinar são alguns dos aspectos implicados nesta questão. Neste contexto de discussão insere-se o presente artigo, que tem por objetivo discutir o caráter socioeducativo das medidas de privação de liberdade e as possibilidades de reinserção social do jovem em conflito com a lei

Adesão às medidas de precaução-padrão: relato de experiência Adhesión a las medidas de precaución padrón: relato de experiencia Adoption of standard precautions: a report

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Maria Helena Baena de Moraes Lopes

1999-10-01

Full Text Available Durante 1993 e 1994 foi realizada reciclagem em Precauções-Padrão para os profissionais de enfermagem do Centro de Atenção Integral à Saúde da Mulher (CAISM. Em 1995 foi avaliada, por observação direta nos setores, a adesão a estas medidas, o uso adequado, a acessibilidade e disponibilidade de luvas e caixas para descarte de materiais pérfuro-cortantes. Registraram-se 60 observações e 232 procedimentos. Em 164 (71% destes houve adoção das medidas, não ocorrendo o mesmo em outros 68 (29%. Evidenciou-se a necessidade de enfatizar a lavagem de mãos e o não-reencape de agulhas.Durante el periodo de 1993 y 1994 se realizó la actualización en medidas de precaución patrón para los profisionales de enfermeria del Centro de Atención Integral a la Salud de la Mujer (CAISM. En 1995, se realizó una evaluación a través de la observación directa en los sectores; la adhesión a estas medidas, el uso adecuado y la disposición de guantes y cajas para descarte de materiales corto-punzantes. Se registraron 60 observaciones e 232 procedimientos, 164 de ellos (71% adoptaron el uso de las medidas y en 68 (29% esto no ocurrió. Es evidente la necesidad de dar énfasis al lavado de las manos y colocar de nuevo la camisa (tapa a las agujas.During 1993 and 1994, a recycling program on Standard Precautions was conducted for the nursing personnel at the Women's Health Centre (CAISM. In 1995, an evaluation was obtained through direct observation of these sectors regarding the adoption of these measures, the adequate use, access and availability of gloves and boxes for the disposal of perforating, sharp material. Sixty observations and 232 procedures were reported. One hundred sixty four procedures (71% adopted these measures and 68 procedures (29% did not. It was evident that the need to wash hands and not to use needles twice should be emphasized.

Arranjos para efeitos fixos e estruturas de (covariâncias residuais para análises de medidas repetidas do peso de bovinos da raça Canchim Fixed effects arrays and residual covariance structures to analyze sequential weights of Canchim beef cattle

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Fábio Luiz Buranelo Toral

2006-10-01

Full Text Available Este trabalho foi realizado com o objetivo de selecionar o arranjo para efeitos fixos e a estrutura de (covariância residual que melhor representam a variabilidade dos pesos dentro do rebanho e dentro dos indivíduos, considerando-se dados de pesos de bovinos analisados como medidas repetidas. Foram utilizados dados de peso de 3.690 bovinos Canchim, obtidos ao nascimento, à desmama, aos 12 e aos 18 meses de idade. Analisaram-se diferentes arranjos para os efeitos fixos (grupos de contemporâneos e/ou efeitos principais de ano, mês ou época de nascimento e sexo do bezerro e diferentes estruturas de (covariâncias para os resíduos, considerando-se ou não alteração da variância residual ao longo da vida do animal e alteração da correlação entre as medidas tomadas em intervalos diferentes. Os resultados indicaram que o arranjo mais adequado dos efeitos fixos para representar a variabilidade dos pesos dos animais dentro do rebanho foi o grupo de contemporâneos formado por ano, mês e sexo do bezerro e que as melhores estruturas de (covariâncias residuais foram a Fator Analítico de Primeira Ordem e a Não Estruturada, que consideram o aumento das variâncias com o aumento da idade do indivíduo e as correlações diferentes para cada par de medidas de peso.The aim of this work was to evaluate arrays of fixed effects and residual covariance structures that best fit the herd and the animal variability to weights at birth, weaning, twelve and eighteen months of 3,690 Canchim animals. Different arrays of fixed effects (contemporary groups and, or the main effects of year, month or season of birth and sex and different residual covariance structures (considering or not change of variance and of correlation between weights at different ages were studied. The results indicated that the most adequate array of fixed effects to fit herd variability was the contemporary group of year, month and sex. The best residual covariance structures were

El fracaso escolar y los enfoques de aprendizaje: medidas para la inclusión educativa

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Ana Belén Mirete Ruiz

2015-01-01

Full Text Available El índice de fracaso escolar existente actualmente en España resulta muy preocupante a pesar de las numerosas reformas educativas que se han llevado a cabo en los últimos años. Para analizar los factores motivacionales y de estrategias de aprendizaje que pueden estar incidiendo en la calidad del aprendizaje de los estudiantes se ha realizado una investigación con 281 estudiantes de Educación Secundaria Obligatoria a los que se ha aplicado el Cuestionario sobre Procesos de Aprendizaje (CPA. También se les ha planteado una serie de cuestiones sobre aspectos relacionados con la inclusión, los factores que pueden estar influyendo en el fracaso escolar y las medidas de mejora del rendimiento académico aplicadas por los estudiantes según sus enfoques de aprendizaje. Con ello se ha podido identificar las características de los aprendizajes de este grupo de estudiantes y se han planteado una serie de propuestas de mejora que de ser aplicadas podrían repercutir en la calidad de sus aprendizajes, en la mejora de su rendimiento académico y en minimizar los nefastos efectos del fracaso escolar en este nivel educativo.

Probing neutrino dark energy with extremely high-energy cosmic neutrinos

International Nuclear Information System (INIS)

Ringwald, A.; Schrempp, L.

2006-06-01

Recently, a new non-Standard Model neutrino interaction mediated by a light scalar field was proposed, which renders the big-bang relic neutrinos of the cosmic neutrino background a natural dark energy candidate, the so-called Neutrino Dark Energy. As a further consequence of this interaction, the neutrino masses become functions of the neutrino energy densities and are thus promoted to dynamical, time/redshift dependent quantities. Such a possible neutrino mass variation introduces a redshift dependence into the resonance energies associated with the annihilation of extremely high-energy cosmic neutrinos on relic anti-neutrinos and vice versa into Z-bosons. In general, this annihilation process is expected to lead to sizeable absorption dips in the spectra to be observed on earth by neutrino observatories operating in the relevant energy region above 10 13 GeV. In our analysis, we contrast the characteristic absorption features produced by constant and varying neutrino masses, including all thermal background effects caused by the relic neutrino motion. We firstly consider neutrinos from astrophysical sources and secondly neutrinos originating from the decomposition of topological defects using the appropriate fragmentation functions. On the one hand, independent of the nature of neutrino masses, our results illustrate the discovery potential for the cosmic neutrino background by means of relic neutrino absorption spectroscopy. On the other hand, they allow to estimate the prospects for testing its possible interpretation as source of Neutrino Dark Energy within the next decade by the neutrino observatories ANITA and LOFAR. (Orig.)

Neutrino physics

International Nuclear Information System (INIS)

Gil-Botella, I.

2011-01-01

The fundamental properties of neutrinos are reviewed in these lectures. The first part is focused on the basic characteristics of neutrinos in the Standard Model and how neutrinos are detected. Neutrino masses and oscillations are introduced and a summary of the most important experimental results on neutrino oscillations to date is provided. Then, present and future experimental proposals are discussed, including new precision reactor and accelerator experiments. Finally, different approaches for measuring the neutrino mass and the nature (Majorana or Dirac), of neutrinos are reviewed. The detection of neutrinos from supernovae explosions and the information that this measurement can provide are also summarized at the end. (author)

Neutrino mass and the solar neutrino problem

International Nuclear Information System (INIS)

Wolfenstein, L.

1987-01-01

Theoretical ideas about neutrino mass based on grand-unified theories are reviewed. These give the see-saw formula in which neutrino mass is inversely proportional to a large mass scale M. For M between 10/sup 11/ and 10/sup 15/ Gev the study of solar neutrinos appears to be the best probe of neutrino masses and mixings

Adaptacao transcultural e confiabilidade de medidas de caracteristicas autorreferidas de vizinhanca no ELSA-Brasil

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Simone M Santos

2013-06-01

Full Text Available OBJETIVO: Descrever o processo de adaptação de escalas de medida de características de vizinhança para o português brasileiro. MÉTODOS: As dimensões abordadas foram coesão social, ambiente propício para atividade física, disponibilidade de alimentos saudáveis, segurança em relação a crimes, violência percebida e vitimização. No processo de adaptação foram avaliados aspectos de equivalência entre as escalas originais e respectivas versões para o português. A confiabilidade teste-reteste foi avaliada em submostra de 261 participantes do Estudo Longitudinal de Saúde do Adulto (ELSA-Brasil que responderam ao mesmo questionário em dois momentos distintos em um intervalo de tempo de sete a 14 dias entre as duas aplicações. RESULTADOS: Os aspectos de equivalência avaliados mostraram-se adequados. O coeficiente de correlação intraclasse variou entre 0,83 (IC95% 0,78;0,87 para Coesão Social e 0,90 (IC95% 0,87;0,92 para Ambiente para Atividade Física. As escalas apresentaram consistência interna (alfa de Cronbach que variaram entre 0,60 e 0,84. CONCLUSÕES: As medidas autorreferidas de características de vizinhança tiveram reprodutibilidade muito boa e boa consistência interna. Os resultados sugerem que essas escalas podem ser utilizadas em estudos com população brasileira que apresente características similares àquelas do ELSA-Brasil.

Neutrino magnetic moments and the solar neutrino problem

Energy Technology Data Exchange (ETDEWEB)

Akhmedov, E.Kh. [Washington Univ., Seattle, WA (United States). Inst. for Nuclear Theory]|[Valencia Univ. (Spain). Dept. de Fisica Teorica

1994-08-01

Present status of the neutrino magnetic moment solutions of the solar neutrino problem is reviewed. In particular, we discuss a possibility of reconciling different degrees of suppression and time variation of the signal (or lack of such a variation) observed in different solar neutrino experiments. It is shown that the resonant spin-flavor precession of neutrinos due to the interaction of their transitions magnetic moments with solar magnetic field can account for all the available solar neutrino data. For not too small neutrino mixing angles (sin 2{theta}{sub o} {approx_gt} 0.2 the combined effect of the resonant spin-flavor precession and neutrino oscillations can result in an observable flux of solar {bar {nu}}{sub e}`s.

Neutrino magnetic moments and the solar neutrino problem

International Nuclear Information System (INIS)

Akhmedov, E.Kh.; Valencia Univ.

1994-01-01

Present status of the neutrino magnetic moment solutions of the solar neutrino problem is reviewed. In particular, we discuss a possibility of reconciling different degrees of suppression and time variation of the signal (or lack of such a variation) observed in different solar neutrino experiments. It is shown that the resonant spin-flavor precession of neutrinos due to the interaction of their transitions magnetic moments with solar magnetic field can account for all the available solar neutrino data. For not too small neutrino mixing angles (sin 2θ o approx-gt 0.2 the combined effect of the resonant spin-flavor precession and neutrino oscillations can result in an observable flux of solar bar ν e 's

Toma de medidas usando fotografías digitales: Repaso experimental a procedimientos existentes, posibles fuentes de error, reproductividad del método y usos potenciales

OpenAIRE

Bustos-Pérez, Guillermo

2016-01-01

El uso de medios digitales para el análisis arqueológico está a la orden del día. Un ejemplo es el uso de fotografías digitales para la obtención de medidas en diferentes objetos. Se presenta aquí un repaso al procedimiento de medida de filos en lascas publicado por Eren et al., (2008), una experiencia de reproductividad del método, y una ampliación experimental de sus potenciales usos para el análisis de industria lítica. Los resultados muestran que se trata de un procedimient...

Physics of neutrino flavor transformation through matter–neutrino resonances

Energy Technology Data Exchange (ETDEWEB)

Wu, Meng-Ru, E-mail: mwu@theorie.ikp.physik.tu-darmstadt.de [Institut für Kernphysik (Theoriezentrum), Technische Universität Darmstadt, Schlossgartenstraße 2, 64289 Darmstadt (Germany); Duan, Huaiyu, E-mail: duan@unm.edu [Department of Physics and Astronomy, University of New Mexico, Albuquerque, NM 87131 (United States); Qian, Yong-Zhong, E-mail: qian@physics.umn.edu [School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455 (United States)

2016-01-10

In astrophysical environments such as core-collapse supernovae and neutron star–neutron star or neutron star–black hole mergers where dense neutrino media are present, matter–neutrino resonances (MNRs) can occur when the neutrino propagation potentials due to neutrino–electron and neutrino–neutrino forward scattering nearly cancel each other. We show that neutrino flavor transformation through MNRs can be explained by multiple adiabatic solutions similar to the Mikheyev–Smirnov–Wolfenstein mechanism. We find that for the normal neutrino mass hierarchy, neutrino flavor evolution through MNRs can be sensitive to the shape of neutrino spectra and the adiabaticity of the system, but such sensitivity is absent for the inverted hierarchy.

Neutrinos today

International Nuclear Information System (INIS)

Pontecorvo, B.; Bilen'kij, S.

1987-01-01

After the famous 1983 discovery of intermediate W, Z 0 bosons it may be stated with certainty that W, Z 0 are entirely responsible for the production of neutrinos and for their interactions. Neutrino physics notions are presented from this point of view in the first four introductory, quite elementary, paragraphs of the paper. The following seven paragraphs are more sophisticated. They are devoted to the neutrino mass and neutrino mixing question, which is the most actual problem in today neutrino physics. Vacuum neutrino oscillations, matter neutrino oscillations and netrinoless double-decay are considered. Solar neutrino physics is discussed in some detail from the point of view of vacuum and matter neutrino oscillations. The role played by neutrinos in the Universe is briefly considered. In the last paragraph there discussed the probable observation by different groups of neutrinos connected with the Supernova 1987 A: the first observation of gravitational star collapse (at least the general rehearsal of such observation) opens up a new era in astronomy of today exerimental physics and astrophysics is presented at the end of the paper in the form of a Table

Neutrino mass?

International Nuclear Information System (INIS)

Kayser, B.

1992-01-01

After arguing that we should be looking for evidence of neutrino mass, we illustrate the possible consequences of neutrino mass and mixing. We then turn to the question of whether neutrinos are their own antiparticles, and to the process which may answer this question: neutrinoless double beta decay. Next, we review the proposed Mikheyev-Smirnov-Wolfenstein solution to the solar neutrino problem, and discuss models which can generate neutrino electromagnetic moments large enough to play a role in the sun. Finally, we consider how the possible 17 keV neutrino, if real, would fit in with everything we know about neutrinos. (orig.)

Probing Neutrino Properties with Long-Baseline Neutrino Beams

International Nuclear Information System (INIS)

Marino, Alysia

2015-01-01

This final report on an Early Career Award grant began in April 15, 2010 and concluded on April 14, 2015. Alysia Marino's research is focussed on making precise measurements of neutrino properties using intense accelerator-generated neutrino beams. As a part of this grant, she is collaborating on the Tokai-to-Kamioka (T2K) long-baseline neutrino experiment, currently taking data in Japan, and on the Deep Underground Neutrino Experiment (DUNE) design effort for a future Long-Baseline Neutrino Facility (LBNF) in the US. She is also a member of the NA61/SHINE particle production experiment at CERN, but as that effort is supported by other funds, it will not be discussed further here. T2K was designed to search for the disappearance of muon neutrinos (?_?) and the appearance of electron neutrinos (?_e), using a beam of muon neutrino beam that travels 295 km across Japan towards the Super-Kamiokande detector. In 2011 T2K first reported indications of ?_e appearance, a previously unobserved mode of neutrino oscillations. In the past year, T2K has published a combined analysis of ?_? disappearance and ?_e appearance, and began collecting taking data with a beam of anti-neutrinos, instead of neutrinos, to search for hints of violation of the CP symmetry of the universe. The proposed DUNE experiment has similar physics goals to T2K, but will be much more sensitive due to its more massive detectors and new higher-intensity neutrino beam. This effort will be very high-priority particle physics project in the US over the next decade.

Physics of neutrino flavor transformation through matter–neutrino resonances

Directory of Open Access Journals (Sweden)

Meng-Ru Wu

2016-01-01

Full Text Available In astrophysical environments such as core-collapse supernovae and neutron star–neutron star or neutron star–black hole mergers where dense neutrino media are present, matter–neutrino resonances (MNRs can occur when the neutrino propagation potentials due to neutrino–electron and neutrino–neutrino forward scattering nearly cancel each other. We show that neutrino flavor transformation through MNRs can be explained by multiple adiabatic solutions similar to the Mikheyev–Smirnov–Wolfenstein mechanism. We find that for the normal neutrino mass hierarchy, neutrino flavor evolution through MNRs can be sensitive to the shape of neutrino spectra and the adiabaticity of the system, but such sensitivity is absent for the inverted hierarchy.

Neutrino sunshine

International Nuclear Information System (INIS)

Anon.

1993-01-01

Full text: On 10 June 1992, at the Neutrino 92 meeting in Grenada, Spain, Till Kirsten of Heidelberg's Max Planck Institute reported that neutrinos from sunshine had been seen. Most of the energy pumped out by the Sun comes from the fusion of protons into alpha particles, a process which also liberates neutrinos. While it takes about a million years for radiant energy formed in the deep interior of the Sun to fight its way to the surface, the highly penetrating neutrinos emerge almost immediately. It was in 1970 that Ray Davis and his team began taking data with a tank containing 615 tons of perchloroethylene (dry cleaning fluid) 1500 metres underground in the Homestake gold mine, South Dakota. The observed signal is consistently smaller than what is expected. This 'solar neutrino problem' was confirmed by the Kamioka mine experiment in Japan, looking at the Cherenkov light released by neutrino interactions in some 700 tons of water. However these experiments are only sensitive to a tiny high energy tail of the solar neutrino spectrum, and to understand what is going on needs measurements of the primary neutrinos from proton fusion. To get at these neutrinos, two large new detectors, using gallium and sensitive to these lower energy particles, have been built and commissioned in the past few years. The detectors are SAGE ('Soviet' American Gallium Experiment) in the Baksan Neutrino Observatory in the Caucasus, and Gallex, a team from France, Germany, Israel, Italy and the US in the Italian Gran Sasso underground Laboratory. At Grenada, Kirsten reported unmistakable signs of solar neutrinos of proton origin recorded in Gallex. SAGE and Gallex do not yet have enough data to unambiguously fix the level of primary solar neutrinos reaching the Earth, and the interpretation of the interim results tends to be subjective. However after 23 years of conditioning through watching the solar neutrinos' high energy tail, the prospect of a neutrino

Acquire information about neutrino parameters by detecting supernova neutrinos

OpenAIRE

Huang, Ming-Yang; Guo, Xin-Heng; Young, Bing-Lin

2010-01-01

We consider the supernova shock effects, the Mikheyev-Smirnov-Wolfenstein (MSW) effects, the collective effects, and the Earth matter effects in the detection of type II supernova neutrinos on the Earth. It is found that the event number of supernova neutrinos depends on the neutrino mass hierarchy, the neutrino mixing angle $\\theta_{13}$, and neutrino masses. Therefore, we propose possible methods to identify the mass hierarchy and acquire information about $\\theta_{13}$ and neutrino masses ...

Aplicação de medidas cefalométricas em 3D-TC: Application of cephalometric measurements in 3D-TC

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Patrícia de Medeiros Loureiro Lopes

2007-01-01

Full Text Available OBJETIVO: o objetivo desta pesquisa foi avaliar a precisão e acurácia (validade de medidas cefalométricas lineares em imagens reconstruídas em terceira dimensão (3D, pela técnica de volume, a partir da tomografia computadorizada (TC multislice. METODOLOGIA: o material da pesquisa consistiu de 10 (dez crânios secos, previamente selecionados, sem distinção de etnia ou gênero, os quais foram submetidos à TC multislice 16 cortes com 0,5mm de espessura por 0,3mm de intervalo de reconstrução. Posteriormente, os dados obtidos foram enviados para uma estação de trabalho independente, contendo o programa Vitrea®. Os pontos cefalométricos (n=13 foram localizados e as respectivas medidas ósseas lineares (n=15 foram realizadas por 2 examinadores, previamente treinados, medindo cada um duas vezes, independentemente, em 3D. As medidas físicas foram obtidas por um terceiro examinador, utilizando um paquímetro digital. A análise dos dados foi realizada mediante um estudo comparativo entre as medidas inter e intra-examinadores, em 3D-TC, e entre estas e as medidas físicas obtidas diretamente nos crânios, utilizando ANOVA (análise de variância. RESULTADOS: não foram encontradas diferenças estatisticamente significantes entre os valores das medidas inter e intra-examinadores, nem entre as medidas físicas e em 3D, com p>0,6 para todas as medidas. O erro percentual foi de 2,05% para as medidas interexaminadores e de 2,11% para as medidas intra-examinadores. A média do erro percentual entre as medidas físicas e em 3D variou de 0,96% a 1,47%. CONCLUSÃO: todas as medidas cefalométricas lineares foram consideradas precisas e acuradas utilizando a técnica de volume em 3D por meio da TC multislice.AIM: To test the precision and accuracy of conventional linear cephalometric measurements in 3D reconstructed images using a multislice CT. METHODS: The study population consisted of 10 dry skulls, previously selected, without distinction of

Medidas cautelares innominadas en la protección de los derechos de autor y conexos en Colombia

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Nixon Jefrey Gil Aguirre

2016-12-01

Full Text Available Actualmente, el ejercicio de funciones jurisdiccionales atribuidas a las autoridades administrativas ha generado interpretaciones judiciales confusas, en la aplicación de medidas cautelares innominadas para la protección de derechos de autor y conexos en Colombia; así lo evidencia el análisis realizado a las medidas cautelares descritas en la Ley 1493 del año 2011, que otorgó competencias de inspección, vigilancia y control sobre las sociedades de gestión colectiva de derechos de autor y conexos; en este sentido se requiere describir las funciones jurisdiccionales de la Dirección Nacional de Derecho de Autor respecto a las medidas cautelares y su importancia en la protección de los derechos de autor y conexos, al igual que analizar las medidas cautelares innominadas desde su origen, las características y lo propuesto por la Corte Constitucional en materia de funciones jurisdiccionales de la Dirección Nacional de Derecho de Autor y respecto de la procedencia de las medidas cautelares innominadas como competencia de esta entidad. Se concluye que las medidas cautelares nominadas no son suficientes, y que se hace necesario acudir a las medidas cautelares innominadas, como herramienta jurídica del funcionario administrativo, sin que ello implique arbitrariedad y prejuzgamiento en el proceso.

Medidas de vigilancia y contención de la influenza aviar en aves. Implicaciones para la salud pública

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Alejandro Arteaga Rodríguez

2006-01-01

Full Text Available La Influenza Aviar es una enfermedad infecciosa que afecta principalmente a las aves, producida por virus de la gripe A, en la mayoría de los casos de baja patogenicidad. Debido a la rápida mutación de estos virus a formas altamente patógenas, el nivel de riesgo para la sanidad animal y la salud pública puede ser alto. Desde el año 2003, está teniendo lugar un brote de Influenza Aviar en aves producido por el subtipo H5N1 de alta patogenicidad, con transmisión y afectación humana y que presenta un riesgo potencial de producir una nueva pandemia de gripe. Ante estos brotes, es fundamental la colaboración entre los sectores implicados de la Sanidad Animal y Salud Pública que permita localizar con precisión las zonas de actividad de la enfermedad en los animales e intensificar en ellas la vigilancia de los casos en humanos. Las medidas de control de la enfermedad en animales deben ser compatibles con la reducción del riesgo de exposición humana. El objetivo de este artículo es hacer una revisión de las medidas generales desarrolladas contra la Influenza Aviar en aves, destacando los aspectos de coordinación y comunicación entre las autoridades de Sanidad Animal y Salud Pública, teniendo en cuenta que la legislación está sujeta a una renovación rápida y constante en consonancia con la dinámica de esta enfermedad.

Performance of cylindrical leaf wetness duration sensors in a tropical climate condition Desempenho de sensores cilíndricos para medida da duração do período de molhamento foliar em condições de clima tropical

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Eduardo Alvarez Santos

2008-12-01

conditions, where LWD measured by cylinders were two hours longer than by flat plate sensors.Medidas da duração do período de molhamento (DPM são necessárias para diversos sistemas de alerta fitossanitário, uma vez que a DPM é uma variável importante para a epidemiologia. O sensor cilíndrico é um sensor eletrônico barato e que pode ser facilmente produzido. Esse sensor foi inicialmente projetado para medir DPM em cebola, contudo alguns estudos indicam que ele também pode ser utilizado em estações meteorológicas e outras culturas. Portanto, o objetivo deste estudo foi avaliar o desempenho de sensores cilíndricos sob condições tropicais, no Brasil, tendo-se as medidas obtidas pelo sensor de placa como referência. Antes de serem instalados no campo, todos os sensors eletrônicos utilizados no estudo (placa e cilíndricos foram pintados com tinta latex branca e, em seguida, submetidos a tratamento térmico. Testes de laboratório foram realizados para determinar um limiar de resistência, a partir do qual os sensores seriam considerados molhados, e o tempo de reposta dos sensores ao molhamento. No campo, todos os sensores foram inicialmente instalados na horizontal a 30 cm de altura sobre gramado, visando a avaliar a variabilidade entre os sensores de DPM. A variabilidade entre os sensores cilíndricos na horizontal foi reduzida com a adoção de um limiar de resistência específico para cada sensor. O coeficiente médio de variação para DPM diária medida pelos sensores cilíndricos foi igual a 9,7%. Posteriormente, os sensores cilíndricos foram instalados em 5 ângulos diferentes com a horizontal: 0, 15, 30, 45, and 60º. As medidas obtidas por esses sensores são comparáveis com a medida padrão, fornecida por sensores de placa instalados a 45º e mesma altura. A mudança do ângulo de instação não teve efeito sistemático sobre as medidas da DPM para as condições locais, uma vez que as correlações entre as medidas dos sensores de placa e

A combined treatment of neutrino decay and neutrino oscillations

International Nuclear Information System (INIS)

Lindner, Manfred; Ohlsson, Tommy; Winter, Walter

2001-01-01

Neutrino decay in vacuum has often been considered as an alternative to neutrino oscillations. Because nonzero neutrino masses imply the possibility of both neutrino decay and neutrino oscillations, we present a model-independent formal treatment of these combined scenarios. For that, we show for the example of Majoron decay that in many cases decay products are observable and may even oscillate. Furthermore, we construct a minimal scenario in which we study the physical implications of neutrino oscillations with intermediate decays

Experimental neutrino physics

CERN Document Server

Link, Jonathan M

2018-01-01

Neutrinos have a smaller mass than any other known particle and are the subject of intense recent studies, as well as this book. The author provides a coherent introduction to the necessary theoretical background and experimental methods used by modern neutrino physicists. It’s designed as a one-stop reference addressing what is currently known about the neutrino hypothesis, discovery of the neutrino, theory of weak interactions, solar neutrino puzzle, and neutrino oscillation. It then gives a detailed account of practical approaches for study of precision oscillations, neutrino mass and other neutrino properties, sterile neutrinos, and neutrino messengers from space and Earth’s interior.

Ato infracional e medida socioeducativa: representações de adolescentes em L.A.

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Bianca Izoton Coelho

2013-01-01

Full Text Available A pesquisa analisou as representações sociais de ato infracional e medida socioeducativa em adolescentes em conflito com a lei. Utilizou-se, como aporte teórico e metodológico, a Teoria das Representações Sociais. Participaram da pesquisa quarenta e seis adolescentes que cumpriam, há mais de três meses, a medida de Liberdade Assistida. Os dados foram coletados, por meio de entrevistas, com um roteiro semiestruturado e consistiram na técnica das evocações livres por meio dos termos ato infracional e medida socioeducativa. Utilizou-se o software EVOC para análise das evocações emitidas. Os resultados apontaram como caracterização socioeconômica dos adolescentes: renda familiar baixa, baixo nível de escolaridade, local de residência precário, etnias afro-descendentes predominantes e distanciamento da religião. As representações sociais de ato infracional relacionaram-se aos tipos de atos infracionais e às suas causas e consequências. As representações sociais de medida socioeducativa relacionaram-se a ações positivas em que, além da aprendizagem, houve a possibilidade de mudança.

Diferencia en la medida centrada y descentrada del espesor y volumen retiniano con Tomografía de Coherencia Óptica (OCT 3D)

OpenAIRE

Carrero Peñaranda, Rocio

2013-01-01

Se realizaron diferentes medidas centradas y descentradas del espesor y volumen retiniano con OCT para determinar si un ligero descentramiento en la medida puede ocasionar una medida errónea del espesor macular y, en consecuencia, una mala decisión por parte del oftalmólogo a la hora de decidir un tratamiento en pacientes con edema macular. Máster en Física de los sistemas de diagnóstico, tratamiento y protección en Ciencias de la Salud

Medidas Sanitarias y Fitosanitarias, ¿Barreras al Comercio?: el Caso Peruano en el Asia-Pacífico

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Marcelo Alonso Valverde Arevalo

2016-01-01

Full Text Available Los aranceles han dejado de representar la principal barrera al comercio exterior, debido a la reducción constante de éstos en el ámbito multilateral o bilateral. Contrariamente, las medidas no arancelarias han ido en aumento, siendo la principal preocupación para las exportaciones mundiales. En este escenario, se presentan las medidas sanitarias y fitosanitarias, las cuales sirven para proteger la salud de las personas, animales y plantas en contra de riesgos asociados con enfermedades, pestes u otros; sin embargo, por la naturaleza de las mismas pueden distorsionar el comercio hasta ser utilizadas con fines proteccionistas en favor de las industrias nacionales de los países importadores. El presente artículo cuestiona si es que a pesar de contar con una serie de acuerdos comerciales internacionales, los cuales han disminuido progresivamente los aranceles, el Perú ha logrado un acceso real al mercado del Asia-Pacífico con productos agropecuarios y pesqueros. En ese sentido, se presentan casos históricos y pendientes en materia de acceso a mercados por medidas de carácter sanitario o fitosanitario, tal como el acceso de paltas a Japón. Asimismo, se analizan las disposiciones de los acuerdos comerciales en materia de medidas sanitarias y fitosanitarias y se presentan las potenciales oportunidades que se establecen en estos acuerdos, a fin de agilizar el acceso a mercados internacionales, y que no se han aprovechado.

Neutrino physics

CERN Document Server

Hernandez, P.

2016-01-01

This is the writeup of the lectures on neutrino physics delivered at various schools: TASI and Trieste in 2013 and the CERN-Latin American School in 2015. The topics discussed in this lecture include: general properties of neutrinos in the SM, the theory of neutrino masses and mixings (Dirac and Majorana), neutrino oscillations both in vacuum and in matter, as well as an overview of the experimental evidence for neutrino masses and of the prospects in neutrino oscillation physics. We also briefly review the relevance of neutri- nos in leptogenesis and in beyond-the-Standard-Model physics.

Neutrino astrophysics

International Nuclear Information System (INIS)

Roulet, E.

2001-01-01

A general overview of neutrino physics and astrophysics is given, starting with a historical account of the development of our understanding of neutrinos and how they helped to unravel the structure of the Standard Model. We discuss why it is so important to establish if neutrinos are massive and introduce the main scenarios to provide them a mass. The present bounds and the positive indications in favor of non-zero neutrino masses are discussed, including the recent results on atmospheric and solar neutrinos. The major role that neutrinos play in astrophysics and cosmology is illustrated. (author)

FUNCIONES EJECUTIVAS EN NIÑOS Y ADOLESCENTES: IMPLICACIONES DEL TIPO DE MEDIDAS DE EVALUACIÓN EMPLEADAS PARA SU VALIDEZ EN CONTEXTOS CLÍNICOS Y EDUCATIVOS

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Trinidad García Fernández

2014-09-01

Full Text Available Las funciones ejecutivas implican un amplio rango de habilidades relacionadas con la regulación del pensamiento, el comportamiento y el propio estado emocional. Teniendo en cuenta la variedad de componentes que forman este constructo, no es sorprendente que su evaluación plantee ciertas dificultades. En este sentido, pese a que numerosos estudios han mostrado la importancia de dichos componentes como determinantes del desempeño académico y social, así como su utilidad en el diagnóstico y la intervención en diversas problemáticas durante la infancia y la adolescencia, aspectos como la validez ecológica de las medidas tradicionalmente empleadas para su evaluación, imponen hoy ciertas limitaciones a la validez y generalización de los resultados obtenidos en este ámbito. El objetivo de este trabajo es analizar las características de las medidas de evaluación más ampliamente empleadas y su grado de aplicabilidad en contextos clínicos y educativos, de lo cual se desprenden una serie de implicaciones prácticas.

CONTROL EJECUTIVO Y FLUIDEZ VERBAL EN POBLACIÓN INFANTIL: MEDIDAS CUANTITATIVAS, CUALITATIVAS Y TEMPORALES

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JULIÁN MARINO

2011-01-01

Full Text Available Para evaluar la evocación de palabras asociadas bajo una consigna de prueba de fluidez verbal (PFV se tienen en cuenta la cantidad de palabras producidas, las asociaciones categoriales y fonológicas entre ellas y el tiempo en que son evocadas. A continuación se presenta un estudio que se realizó aplicando PFV semánticas y fonológicas en una población infantil (8 - 12 años de la ciu dad de Granada (España, que tuvo por objetivos: (1 revisar las tradicionales medidas en PFV, (2 actualizar los índices temporales de medición y (3 presentar combinaciones de éstas con el fin de establecer con mayor precisión la participación del control ejecutivo en PFV. Se encontraron resultados significativos entre los que se destaca que la combinación entre la medida temporal de evocación de palabras conjuntas y la cualitativa de palabras en relación cluster podría aislar con mayor fiabilidad el compromiso de funciones ejecutivas como el control inhibitorio y la flexibilidad cognitiva. Esto se determinó empleando medidas de regresión, ingre sando como variables independientes funciones ejecutivas y como variables dependientes cada una de las medidas de Fluidez Verbal. Para la mencionada combinación de palabras conjuntas - palabras en relación cluster (PFV fonológica letra P se halló un R2 de .41 (p = .000 ingresando como variables predictoras el Trail Making B y la parte Color - Palabra de la versión Trenerry del paradigma Stroop (Lezak, 1995. Se describen también otras posibilidades de medición temporales - cualitativas y su posible utilidad clínica y de investigación.

Neutrino oscillation study in the muon neutrino → electron neutrino channel at the Brookhaven accelerator

International Nuclear Information System (INIS)

Astier, P.

1987-09-01

The E816 experiment described in this thesis is devoted to a neutrino oscillation search at the Brookhaven AGS. The method used here is to look with a fine grained calorimeter for the appearence of electron neutrino in a muon neutrino beam. After recalling the theoretical treatment of the neutrino mass problem, the experimental phenomenology of massive neutrinos and more specifically neutrino oscillations is reviewed. The experiment itself is then extensively described, both on the technical side (detector, beam, simulation) and on the analysis side. In particular the statistical separation of the electromagnetic showers from electrons - our signal - and from photons - our background - treated in detail. The present analysis is based on 2/3 of the final statistics and it leads to the - preliminary - observation of an electron excess in the neutrino interactions yielding 19 ± 15.6 (stat) ± 7 (syst) [fr

Signatures of the neutrino mass hierarchy in supernova neutrinos

International Nuclear Information System (INIS)

Chiu, S.H.; Huang, Chu-Ching; Lai, Kwang-Chang

2015-01-01

The undetermined neutrino mass hierarchy may leave an observable imprint on the neutrino fluxes from a core-collapse supernova (SN). The interpretation of the observables, however, is subject to the uncertain SN models and the flavor conversion mechanism of neutrinos in a SN. We attempt to propose a qualitative interpretation of the expected neutrino events at terrestrial detectors, focusing on the accretion phase of the neutrino burst. The flavor conversions due to neutrino self-interaction, the MSW effect, and the Earth regeneration effect are incorporated in the calculation. It leads to several distinct scenarios that are identified by the neutrino mass hierarchies and the collective flavor transitions. Consequences resulting from the variation of incident angles and SN models are also discussed

La variable latente calidad medida a través del modelo de Rasch.

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Guerrero, Mª M.

1997-01-01

Full Text Available La obtención de aceites de oliva de calidad requiere unos cuidados especiales en todas y cada una de las sucesivas fases de elaboración de los mismos, es una cadena que comienza en el olivo y termina en el consumo. Condición indispensable para ello es conocer las características organolépticas del aceite (a fin de potenciar sus atributos y eliminar, en la medida de los posible, sus defectos, y la influencia del proceso de elaboración en las mismas. El control y medida de estos caracteres se hará mediante las catas, realizadas por expertos catadores utilizando para ello las fichas de cata del Consejo Oleícola Internacional. El modelo de Rasch, que emplearemos para obtener la evaluación sensorial de los aceites de oliva virgen, nos permitirá no sólo dar una calificación organoléptica global al aceite (que ya podemos realizar sin necesidad de aplicar ningún método, siguiendo la metodología de valoración del Consejo Oleícola Internacional, sino también clasificar y medir los factores sensoriales que intervienen en la calidad, lo que nos permitirá realizar las acciones oportunas encaminadas a obtener aceites de oliva de cualidades óptimas.

Assistência de enfermagem em unidade de internação neonatal: medidas para prevenção de infecções hospitalares Asistencia de enfermería en unidades de hospitalización neonatal: medidas para prevención de infecciones hospitalarias Nursing care in neonatal units: measures for the prevention of hospital infections

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Ivone Kamada

1997-01-01

Full Text Available A prevenção de infecção em berçários requer cuidados com o ambiente, equipamentos, pessoal e o próprio recém-nascido, pertinentes à assistência de enfermagem. Frente aos problemas relacionados a infecções hospitalares encontrados, esta investigação tem por objetivo verificar a relação entre as medidas prescritivas sobre a Prevenção de Infecção e as atividades efetivas realizadas numa Unidade de Internação Neonatal. As estratégias de investigação adotadas foram a observação participante e a entrevista semi-estruturada possibilitando a coleta de dados. Pudemos ver com este trabalho que as medidas profiláticas têm que ser tomadas em conjunto, num complexo de atividades,fundamentadas em instalações e estrutura adequadas, desempenhadas por uma equipe profissional coesa, onde todos trabalhem com os mesmos objetivos. Tomá-las isoladamente não contribui para o efetivo cumprimento das prescrições.La prevención de infección en salas de recién nacidos, referentes a la asistencia de enfermería, requiere cuidados con el ambiente, equipos, personal y con el propio recién nacido. Frente a los problemas relacionados con la infección hospitalaria encontrados, esta investigación tiene por objetivo verificar la relación entre las medidas prescriptivas sobre la prevención de la infección y las actividades efectivas realizadas en una unidad de intervención neo-natal. Las estrategias de investigación adoptadas, fueron, la observación participante y la entrevista semi-estructurada, posibilitando la colecta de datos. Con este trabajo pudimos ver que las medidas profilácticas tienen que ser tomadas en un conjunto de actividades, basadas en instalaciones y estructuras adecuadas, ejecutadas por un equipo profesional en que todos trabajan con los mismos objetivos. Tomálas aisladamente no contribuye para el efectivo cumplimiento de las prescripciones.The prevention of infection in nurseries requires measures related to

Neutrino astronomy with supernova neutrinos

Science.gov (United States)

Brdar, Vedran; Lindner, Manfred; Xu, Xun-Jie

2018-04-01

Modern neutrino facilities will be able to detect a large number of neutrinos from the next Galactic supernova. We investigate the viability of the triangulation method to locate a core-collapse supernova by employing the neutrino arrival time differences at various detectors. We perform detailed numerical fits in order to determine the uncertainties of these time differences for the cases when the core collapses into a neutron star or a black hole. We provide a global picture by combining all the relevant current and future neutrino detectors. Our findings indicate that in the scenario of a neutron star formation, supernova can be located with precision of 1.5 and 3.5 degrees in declination and right ascension, respectively. For the black hole scenario, sub-degree precision can be reached.

Confianza y capital social: evidencia para México

Directory of Open Access Journals (Sweden)

Rubén Martínez-Cárdenas

2015-01-01

Full Text Available Desde la perspectiva económica la confianza entre los miembros de una sociedad está asociada al funcionamiento eficiente de los mercados, al reforzamiento de contratos y, en general, a la capacidad para generar desarrollo y bienestar. En este artículo exploramos empíricamente los determinantes de la confianza en México, en particular, aislamos la relación entre dos medidas de capital social, una para el individuo y otra para su entorno. Nuestros resultados muestran que la confianza aumenta con estas medidas de capital social y con ausencia de se - gregación es mayor en comunidades pequeñas, a mayor edad y para habitantes del centro-occidente, entre otras.

The solar neutrinos epopee; L'epopee des neutrinos solaires

Energy Technology Data Exchange (ETDEWEB)

Lasserre, Th. [CEA Saclay, Dept. d' Astrophysique, de Physique des Particules, de Physique Nucleaire et de l' Instrumentation Associee, Service de Physique des Particules, 91- Gif sur Yvette (France)

2003-06-01

The 2002 year has been fruitful for the neutrino physics. First, the Sudbury Neutrino Observatory (SNO) experiment has shown that the electron neutrinos {nu}{sub e} emitted by the sun are converted into muon neutrinos ({nu}{sub {mu}}) and tau neutrinos ({nu}{sub {tau}}), thus closing the 30 years old problem of solar neutrinos deficit. This discovery validates the model of nuclear energy production inside the sun but it shakes the theory describing the weak interactions between the fundamental constituents of matter. This theory considers the neutrinos (and the photons) as massless particles, while the taste conversion phenomenon necessarily implies that neutrinos have a mass. In October 2000, the Universe exploration by the cosmic neutrinos is jointly recognized by R. Davis (USA) and M. Koshiba (Japan) who received the Nobel price of physics. Finally, in December 2000, the KamLAND experiment quantitatively demonstrated the neutrinos metamorphosis by detecting a deficit in the flux of electron antineutrinos coming from the surrounding Japanese nuclear reactors. This digest article describes step by step the epopee of solar neutrinos and shows how several generations of physicists have resolved one of the mystery of modern physics. (J.S.)

Supernova Neutrino-Process and Implication in Neutrino Oscillation

Science.gov (United States)

Kajino, T.; Aoki, W.; Fujiya, W.; Mathews, G. J.; Yoshida, T.; Shaku, K.; Nakamura, K.; Hayakawa, T.

2012-08-01

We studied the supernova nucleosynthesis induced by neutrino interactions and found that several isotopes of rare elements like 7Li, 11B, 138La, 180Ta and many others are predominantly produced by the neutrino-process in core-collapse supernovae. These isotopes are strongly affected by the neutrino flavor oscillation due to the MSW (Mikheyev-Smirnov-Wolfenstein) effect. We here propose a new novel method to determine the unknown neutrino oscillation parameters, θ13 and mass hierarchy simultaneously from the supernova neutrino-process, combined with the r-process for heavy-element synthsis and the Galactic chemical evolution on light nuclei.

Neutrino observations from the Sudbury Neutrino Observatory

Energy Technology Data Exchange (ETDEWEB)

Ahmad, Q.R.; Allen, R.C.; Andersen, T.C.; Anglin, J.D.; Barton,J.C.; Beier, E.W.; Bercovitch, M.; Bigu, J.; Biller, S.D.; Black, R.A.; Blevis, I.; Boardman, R.J.; Boger, J.; Bonvin, E.; Boulay, M.G.; Bowler,M.G.; Bowles, T.J.; Brice, S.J.; Browne, M.C.; Bullard, T.V.; Buhler, G.; Cameron, J.; Chan, Y.D.; Chen, H.H.; Chen, M.; Chen, X.; Cleveland, B.T.; Clifford, E.T.H.; Cowan, J.H.M.; Cowen, D.F.; Cox, G.A.; Dai, X.; Dalnoki-Veress, F.; Davidson, W.F.; Doe, P.J.; Doucas, G.; Dragowsky,M.R.; Duba, C.A.; Duncan, F.A.; Dunford, M.; Dunmore, J.A.; Earle, E.D.; Elliott, S.R.; Evans, H.C.; Ewan, G.T.; Farine, J.; Fergani, H.; Ferraris, A.P.; Ford, R.J.; Formaggio, J.A.; Fowler, M.M.; Frame, K.; Frank, E.D.; Frati, W.; Gagnon, N.; Germani, J.V.; Gil, S.; Graham, K.; Grant, D.R.; Hahn, R.L.; Hallin, A.L.; Hallman, E.D.; Hamer, A.S.; Hamian, A.A.; Handler, W.B.; Haq, R.U.; Hargrove, C.K.; Harvey, P.J.; Hazama, R.; Heeger, K.M.; Heintzelman, W.J.; Heise, J.; Helmer, R.L.; Hepburn, J.D.; Heron, H.; Hewett, J.; Hime, A.; Hykawy, J.G.; Isaac,M.C.P.; Jagam, P.; Jelley, N.A.; Jillings, C.; Jonkmans, G.; Kazkaz, K.; Keener, P.T.; Klein, J.R.; Knox, A.B.; Komar, R.J.; Kouzes, R.; Kutter,T.; Kyba, C.C.M.; Law, J.; Lawson, I.T.; Lay, M.; Lee, H.W.; Lesko, K.T.; Leslie, J.R.; Levine, I.; Locke, W.; Luoma, S.; Lyon, J.; Majerus, S.; Mak, H.B.; Maneira, J.; Manor, J.; Marino, A.D.; McCauley, N.; McDonald,D.S.; McDonald, A.B.; McFarlane, K.; McGregor, G.; Meijer, R.; Mifflin,C.; Miller, G.G.; Milton, G.; Moffat, B.A.; Moorhead, M.; Nally, C.W.; Neubauer, M.S.; Newcomer, F.M.; Ng, H.S.; Noble, A.J.; Norman, E.B.; Novikov, V.M.; O' Neill, M.; Okada, C.E.; Ollerhead, R.W.; Omori, M.; Orrell, J.L.; Oser, S.M.; Poon, A.W.P.; Radcliffe, T.J.; Roberge, A.; Robertson, B.C.; Robertson, R.G.H.; Rosendahl, S.S.E.; Rowley, J.K.; Rusu, V.L.; Saettler, E.; Schaffer, K.K.; Schwendener,M.H.; Schulke, A.; Seifert, H.; Shatkay, M.; Simpson, J.J.; Sims, C.J.; et al.

2001-09-24

The Sudbury Neutrino Observatory (SNO) is a water imaging Cherenkov detector. Its usage of 1000 metric tons of D{sub 2}O as target allows the SNO detector to make a solar-model independent test of the neutrino oscillation hypothesis by simultaneously measuring the solar {nu}{sub e} flux and the total flux of all active neutrino species. Solar neutrinos from the decay of {sup 8}B have been detected at SNO by the charged-current (CC) interaction on the deuteron and by the elastic scattering (ES) of electrons. While the CC reaction is sensitive exclusively to {nu}{sub e}, the ES reaction also has a small sensitivity to {nu}{sub {mu}} and {nu}{sub {tau}}. In this paper, recent solar neutrino results from the SNO experiment are presented. It is demonstrated that the solar flux from {sup 8}B decay as measured from the ES reaction rate under the no-oscillation assumption is consistent with the high precision ES measurement by the Super-Kamiokande experiment. The {nu}{sub e} flux deduced from the CC reaction rate in SNO differs from the Super-Kamiokande ES results by 3.3{sigma}. This is evidence for an active neutrino component, in additional to {nu}{sub e}, in the solar neutrino flux. These results also allow the first experimental determination of the total active {sup 8}B neutrino flux from the Sun, and is found to be in good agreement with solar model predictions.

Neutrino Observations from the Sudbury Neutrino Observatory

Science.gov (United States)

Q. R. Ahmad, R. C. Allen, T. C. Andersen, J. D. Anglin, G. B?hler, J. C. Barton, E. W. Beier, M. Bercovitch, J. Bigu, S. Biller, R. A. Black, I. Blevis, R. J. Boardman, J. Boger, E. Bonvin, M. G. Boulay, M. G. Bowler, T. J. Bowles, S. J. Brice, M. C. Browne, T. V. Bullard, T. H. Burritt, K. Cameron, J. Cameron, Y. D. Chan, M. Chen, H. H. Chen, X. Chen, M. C. Chon, B. T. Cleveland, E. T. H. Clifford, J. H. M. Cowan, D. F. Cowen, G. A. Cox, Y. Dai, X. Dai, F. Dalnoki-Veress, W. F. Davidson, P. J. Doe, G. Doucas, M. R. Dragowsky, C. A. Duba, F. A. Duncan, J. Dunmore, E. D. Earle, S. R. Elliott, H. C. Evans, G. T. Ewan, J. Farine, H. Fergani, A. P. Ferraris, R. J. Ford, M. M. Fowler, K. Frame, E. D. Frank, W. Frati, J. V. Germani, S. Gil, A. Goldschmidt, D. R. Grant, R. L. Hahn, A. L. Hallin, E. D. Hallman, A. Hamer, A. A. Hamian, R. U. Haq, C. K. Hargrove, P. J. Harvey, R. Hazama, R. Heaton, K. M. Heeger, W. J. Heintzelman, J. Heise, R. L. Helmer, J. D. Hepburn, H. Heron, J. Hewett, A. Hime, M. Howe, J. G. Hykawy, M. C. P. Isaac, P. Jagam, N. A. Jelley, C. Jillings, G. Jonkmans, J. Karn, P. T. Keener, K. Kirch, J. R. Klein, A. B. Knox, R. J. Komar, R. Kouzes, T. Kutter, C. C. M. Kyba, J. Law, I. T. Lawson, M. Lay, H. W. Lee, K. T. Lesko, J. R. Leslie, I. Levine, W. Locke, M. M. Lowry, S. Luoma, J. Lyon, S. Majerus, H. B. Mak, A. D. Marino, N. McCauley, A. B. McDonald, D. S. McDonald, K. McFarlane, G. McGregor, W. McLatchie, R. Meijer Drees, H. Mes, C. Mifflin, G. G. Miller, G. Milton, B. A. Moffat, M. Moorhead, C. W. Nally, M. S. Neubauer, F. M. Newcomer, H. S. Ng, A. J. Noble, E. B. Norman, V. M. Novikov, M. O'Neill, C. E. Okada, R. W. Ollerhead, M. Omori, J. L. Orrell, S. M. Oser, A. W. P. Poon, T. J. Radcliffe, A. Roberge, B. C. Robertson, R. G. H. Robertson, J. K. Rowley, V. L. Rusu, E. Saettler, K. K. Schaffer, A. Schuelke, M. H. Schwendener, H. Seifert, M. Shatkay, J. J. Simpson, D. Sinclair, P. Skensved, A. R. Smith, M. W. E. Smith, N. Starinsky, T. D. Steiger, R. G. Stokstad, R. S. Storey, B. Sur, R. Tafirout, N. Tagg, N. W. Tanner, R. K. Taplin, M. Thorman, P. Thornewell, P. T. Trent, Y. I. Tserkovnyak, R. Van Berg, R. G. Van de Water, C. J. Virtue, C. E. Waltham, J.-X. Wang, D. L. Wark, N. West, J. B. Wilhelmy, J. F. Wilkerson, J. Wilson, P. Wittich, J. M. Wouters, and M. Yeh

2001-09-24

The Sudbury Neutrino Observatory (SNO) is a water imaging Cherenkov detector. Its usage of 1000 metric tons of D{sub 2}O as target allows the SNO detector to make a solar-model independent test of the neutrino oscillation hypothesis by simultaneously measuring the solar {nu}{sub e} flux and the total flux of all active neutrino species. Solar neutrinos from the decay of {sup 8}B have been detected at SNO by the charged-current (CC) interaction on the deuteron and by the elastic scattering (ES) of electrons. While the CC reaction is sensitive exclusively to {nu}{sub e}, the ES reaction also has a small sensitivity to {nu}{sub {mu}} and {nu}{sub {tau}}. In this paper, recent solar neutrino results from the SNO experiment are presented. It is demonstrated that the solar flux from {sup 8}B decay as measured from the ES reaction rate under the no-oscillation assumption is consistent with the high precision ES measurement by the Super-Kamiokande experiment. The {nu}{sub e} flux deduced from the CC reaction rate in SNO differs from the Super-Kamiokande ES results by 3.3{sigma}. This is evidence for an active neutrino component, in additional to {nu}{sub e}, in the solar neutrino flux. These results also allow the first experimental determination of the total active {sup 8}B neutrino flux from the Sun, and is found to be in good agreement with solar model predictions.

Supernova neutrino detection

International Nuclear Information System (INIS)

Selvi, M.

2005-01-01

Neutrinos emitted during a supernova core collapse represent a unique feature to study both stellar and neutrino properties. After discussing the details of the neutrino emission in the star and the effect of neutrino oscillations on the expected neutrino fluxes at Earth, a review of the detection techniques is presented in this paper, with particular attention to the problem of electron neutrino detection

Non-unitary neutrino propagation from neutrino decay

Energy Technology Data Exchange (ETDEWEB)

Berryman, Jeffrey M., E-mail: jeffreyberryman2012@u.northwestern.edu [Northwestern University, Department of Physics & Astronomy, 2145 Sheridan Road, Evanston, IL 60208 (United States); Gouvêa, André de; Hernández, Daniel [Northwestern University, Department of Physics & Astronomy, 2145 Sheridan Road, Evanston, IL 60208 (United States); Oliveira, Roberto L.N. [Northwestern University, Department of Physics & Astronomy, 2145 Sheridan Road, Evanston, IL 60208 (United States); Instituto de Física Gleb Wataghin Universidade Estadual de Campinas, UNICAMP 13083-970, Campinas, São Paulo (Brazil)

2015-03-06

Neutrino propagation in space-time is not constrained to be unitary if very light states – lighter than the active neutrinos – exist into which neutrinos may decay. If this is the case, neutrino flavor-change is governed by a handful of extra mixing and “oscillation” parameters, including new sources of CP-invariance violation. We compute the transition probabilities in the two- and three-flavor scenarios and discuss the different phenomenological consequences of the new physics. These are qualitatively different from other sources of unitarity violation discussed in the literature.

Non-unitary neutrino propagation from neutrino decay

International Nuclear Information System (INIS)

Berryman, Jeffrey M.; Gouvêa, André de; Hernández, Daniel; Oliveira, Roberto L.N.

2015-01-01

Neutrino propagation in space-time is not constrained to be unitary if very light states – lighter than the active neutrinos – exist into which neutrinos may decay. If this is the case, neutrino flavor-change is governed by a handful of extra mixing and “oscillation” parameters, including new sources of CP-invariance violation. We compute the transition probabilities in the two- and three-flavor scenarios and discuss the different phenomenological consequences of the new physics. These are qualitatively different from other sources of unitarity violation discussed in the literature

Influência da resolução e da distância da câmera nas medidas feitas pelo software de avaliação postural (sapo

Directory of Open Access Journals (Sweden)

Yomara Lima Mota

2011-10-01

Full Text Available O erro na medida de um sistema de avaliação da postura está relacionado com a digitalização, a resolução da câmera, a distância da câmera em relação ao voluntário estudado, entre outros. Estes erros somam-se no procedimento metodológico e muitos deles não são possíveis evitar, porém devem ser conhecidos e quantificados. OBJETIVO: Quantificar o erro na medida realizada pelo SAPO (Software para avaliação postural em diferentes situações experimentais. MÉTODOS: Foram realizadas 16 fotos de um manequim de 1,40m articulado nos planos anterior, posterior, lateral direita e lateral esquerda com câmeras de 3,2 e 12,0 megapixels, posicionadas a 3,0m e a 5,0m de distância do manequim. Para a quantificação do erro, foram calculadas as diferenças das medidas obtidas por meio do SAPO com as medidas feitas diretamente no manequim. Apenas um avaliador realizou o registro das imagens, porém a digitalização no software dos pontos demarcados no manequim foi realizada por três digitalizadores, sendo dois inexperientes e um experiente. RESULTADOS: Os valores médios das medidas horizontais, verticais, angulares e de distância são próximos de zero, embora algumas variáveis angulares apresentem valores maiores, como nas medidas de ângulo Q direito e esquerdo. A câmera com resolução de 3,2 megapixels posicionada a 3m apresentou o menor erro. CONCLUSÃO: O SAPO é um método acurado para uso clínico; são necessários estudos para verificar a influência do plano de posicionamento do voluntário em relação à câmera, o efeito do reposicionamento e da palpação nas medidas oferecidas pelo software.

GENIUS Project, Neutrino Oscillations and Cosmology: Neutrinos Reveal Their Nature ?

International Nuclear Information System (INIS)

Czakon, M.; Studnik, J.; Zralek, M.; Gluza, J.

2000-01-01

The neutrinoless double beta decay as well as any other laboratory experiment has not been able to answer the question of the neutrino's nature. Hints on the answer are available when neutrino oscillations and (ββ) 0ν are considered simultaneously. In this case phenomenologically interesting neutrino mass schemes can lead to non-vanishing and large values of (m ν ). As a consequence, some schemes with Majorana neutrinos can be ruled out even now. If we assume that in addition neutrinos contribute to Hot Dark Matter then the window for Majorana neutrinos is even more restricted, e.g. GENIUS experiment will be sensitive to scenarios with three Majorana neutrinos. (author)

Sterile neutrino

International Nuclear Information System (INIS)

Anon.

2007-01-01

Paper deals with the information on the occurrence of the fields of the sterile neutrinos (the righthanded ones) mixed with the normal neutrinos (the lefthanded ones). Both the Max Plank Radioastronomy Institute and the Los Angeles University assumes that the occurrence of the keV mass sterile neutrinos may explain the dark matter nature, the fast rotation of the observed pulsars and the reionization processes. The issues associated with the possibility to record the sterile neutrinos were analyzed in the course of the Sterile Neutrinos in Astrophysics and Cosmology Workshop (Crans Montana, March 2006 [ru

Neutrinos and Einstein

CERN Document Server

Suzuki, Yoichiro

2005-01-01

A tiny neutrino mass is a clue to the physics beyond the standard model of elementary particle physics. The primary cosmic rays, mostly protons, are created and accelerated to the relativistic energy in supernova remnants. They traverse the universe and reach the earth. The incoming primary cosmic rays interact with the earth's atmosphere to produce secondary particles, which subsequently decay into neutrinos, called atmospheric neutrinos. The atmospheric neutrinos have shown the evidence of the finite neutrino masses through the phenomena called neutrino oscillations. Neutrinos are detected by large detectors underground like, for example, Super-Kamiokande, SNO and KamLAND. Those detectors use large photomultiplier tubes, which make use of the photo-electric effect to convert photons created by the interaction of neutrinos to electrons to form electric pulses. Neutrinos are therefore created and detected by "Einstein" and have step forward beyond the current physics. Neutrinos may also carry a hit to the ori...

Matter-neutrino resonance in a multiangle neutrino bulb model

Science.gov (United States)

Vlasenko, Alexey; McLaughlin, G. C.

2018-04-01

Simulations of neutrino flavor evolution in compact merger environments have shown that neutrino flavor, and hence nucleosynthesis, can be strongly affected by the presence of matter-neutrino resonances (MNRs), where there is a cancelation between the matter and the neutrino potential. Simulations performed thus far follow flavor evolution along a single neutrino trajectory, but self-consistency requires all trajectories to be treated simultaneously, and it has not been known whether MNR phenomena would still occur in multiangle models. In this paper, we present the first fully multi-angle calculations of MNR. We find that familiar MNR phenomena, where neutrinos transform to a greater extent than anti-neutrinos and a feedback mechanism maintains the cancellation between the matter and neutrino potential, still occurs for a subset of angular bins, although the flavor transformation is not as efficient as in the single-angle case. In addition, we find other types of flavor transformation that are not seen in single-angle simulations. These flavor transformation phenomena appear to be robust and are present for a wide range of model parameters, as long as an MNR is present. Although computational constraints currently limit us to models with spherical symmetry, our results suggest that the presence of an MNR generally leads to large-scale neutrino flavor evolution in multiangle systems.

Neutrino Factory

CERN Document Server

Bogomilov, M; Tsenov, R; Dracos, M; Bonesini, M; Palladino, V; Tortora, L; Mori, Y; Planche, T; Lagrange, J  B; Kuno, Y; Benedetto, E; Efthymiopoulos, I; Garoby, R; Gilardoini, S; Martini, M; Wildner, E; Prior, G; Blondel, A; Karadzhow, Y; Ellis, M; Kyberd, P; Bayes, R; Laing, A; Soler, F  J  P; Alekou, A; Apollonio, M; Aslaninejad, M; Bontoiu, C; Jenner, L  J; Kurup, A; Long, K; Pasternak, J; Zarrebini, A; Poslimski, J; Blackmore, V; Cobb, J; Tunnell, C; Andreopoulos, C; Bennett, J  R  J; Brooks, S; Caretta, O; Davenne, T; Densham, C; Edgecock, T  R; Fitton, M; Kelliher, D; Loveridge, P; McFarland, A; Machida, S; Prior, C; Rees, G; Rogers, C; Rooney, M; Thomason, J; Wilcox, D; Booth, C; Skoro, G; Back, J  J; Harrison, P; Berg, J  S; Fernow, R; Gallardo, J  C; Gupta, R; Kirk, H; Simos, N; Stratakis, D; Souchlas, N; Witte, H; Bross, A; Geer, S; Johnstone, C; Mokhov, N; Neuffer, D; Popovic, M; Strait, J; Striganov, S; Morfín, J  G; Wands, R; Snopok, P; Bogacz, S  A; Morozov, V; Roblin, Y; Cline, D; Ding, X; Bromberg, C; Hart, T; Abrams, R  J; Ankenbrandt, C  M; Beard, K  B; Cummings, M  A  C; Flanagan, G; Johnson, R  P; Roberts, T  J; Yoshikawa, C  Y; Graves, V  B; McDonald, K  T; Coney, L; Hanson, G

2014-01-01

The properties of the neutrino provide a unique window on physics beyond that described by the standard model. The study of subleading effects in neutrino oscillations, and the race to discover CP-invariance violation in the lepton sector, has begun with the recent discovery that $\\theta_{13} > 0$. The measured value of $\\theta_{13}$ is large, emphasizing the need for a facility at which the systematic uncertainties can be reduced to the percent level. The neutrino factory, in which intense neutrino beams are produced from the decay of muons, has been shown to outperform all realistic alternatives and to be capable of making measurements of the requisite precision. Its unique discovery potential arises from the fact that only at the neutrino factory is it practical to produce high-energy electron (anti)neutrino beams of the required intensity. This paper presents the conceptual design of the neutrino factory accelerator facility developed by the European Commission Framework Programme 7 EURO$\

Método computadorizado para medida da acuidade visual A computerized method for visual acuity assessment

Directory of Open Access Journals (Sweden)

Patrícia Katayama Kjaer Arippol

2006-12-01

Full Text Available OBJETIVO: Elaborar e validar teste computadorizado para medida da acuidade visual de escolares. MÉTODOS: Foi elaborado teste computadorizado para determinação da acuidade visual utilizando os padrões das tabelas logarítmicas impressas adotadas na clínica oftalmológica. Foram avaliados 90 alunos da primeira série do ensino básico, oito estudantes do curso de Tecnologia Oftálmica da UNIFESP-EPM e 10 pacientes do ambulatório de Estrabismo do Departamento de Oftalmologia da UNIFESP-EPM. Todos os sujeitos foram avaliados pelo mesmo examinador e submetidos ao exame de acuidade visual monocular, pela tabela logarítmica de optotipos E impressa e do novo teste computadorizado no mesmo momento. Os participantes forneceram os seus consentimentos após esclarecimento. RESULTADOS: As análises estatísticas revelaram correlação excelente (r>0,75 entre os dois métodos, apesar da leve tendência apresentada pelo teste computadorizado em superestimar a acuidade visual quando comparado com o padrão-ouro. O teste computadorizado apresentou sensibilidade de 100% e especificidade de 94%. CONCLUSÕES: Os resultados obtidos nos permitem dizer que o teste computadorizado pode ser utilizado como novo recurso para triagem da qualidade visual dos escolares, por ser método rápido, de fácil aplicação, barato, automático e atrativo para as crianças. A automatização desvincula o aplicador da interpretação das respostas dadas pelo aluno testado, garante padronização do procedimento, que favorece as análises de acompanhamento e pode ser realizado por diferentes examinadores. Para melhor compreensão da efetividade do teste como instrumento de triagem visual, seria interessante instituí-lo nas escolas do curso básico, após treinamento dos professores para sua aplicação.PURPOSE: To elaborate and to validate a computerized test for visual acuity screening of school-age children. METHODS: We have created a computerized test for visual acuity

Medida del coeficiente d33 de piezocomposites por interferometría láser

Directory of Open Access Journals (Sweden)

Montero de Espinosa, F.

2002-02-01

Full Text Available The measurement of piezoelectric coefficient d33 is made using devices like the Berlincourt Meter ®, based on a force generator internally calibrated by a reference piezoelectric element which measures the charge ratio Culomb/Newton. For estructures such as piezoelectric composites, formed by materials of very different elastic properties, the measurements made by the described system present a great dispersión which depends on both the size of the pressing head and the aplied arm pressure. This work presents a set of systematic measurements of d33 for several piezocomposite geometries by means of optical interferometry. These measurements are compared with those obtained with the Berlincourt. It is observed that both techniques render closer results as the net step is reduced.La medida del coeficiente piezoeléctrico d33 se realiza utilizando equipos como el Berlincourt Meter ®, basados en un generador de fuerza calibrado internamente por un elemento piezoeléctrico de referencia que mide la relación de carga, Culombio/ Newton. Estos sistemas están absolutamente contrastados, tomando los grupos de investigación sus medidas como estándar. En el caso de estructuras tales como los composites piezoeléctricos, en los que la estructura está formada por materiales de muy distinta elasticidad, bien por este hecho, bien por la misma estructura, las medidas con el sistema descrito presentan una gran dispersión dependiendo del tamaño de la cabeza presionante y la presión del brazo. Dado que en el modelado de resonadores piezocomposite para su uso en aplicaciones con acoplamiento en aire es necesario conocer dicho parámetro sin incertidumbre, se presentan en el trabajo una serie de medidas sistemáticas de dicho coeficiente para varias geometrías de piezocomposites utilizando interferometría óptica. Se relaciona así mismo estas medidas con el resultado obtenido con el equipo estándar antes referido observando como cuanto más pequeño es

Majorana mass term, Dirac neutrinos and selective neutrino oscillations

International Nuclear Information System (INIS)

Leung, C.N.

1987-01-01

In a theory of neutrino mixing via a Majorana mass term involving only the left-handed neutrinos there exist selection rules for neutrino oscillations if true Dirac and/or exactly zero mass eigenstates are present. In the case of three neutrino flavours no oscillation is allowed if the mass spectrum contains one Dirac and one nondegenerate Majorana massive neutrino. The origin of these selection rules and their implications are discussed and the number of possible CP-violating phases in the lepton mixing matrix when Dirac and Majorana mass eigenstates coexist is given. (orig.)

Eclipsed neutrinos

International Nuclear Information System (INIS)

Anon.

1995-01-01

Full text: The total solar eclipse visible in Southern Asia on 24 October provided an opportunity for an unusual physics experiment. At face value, the levels of solar neutrinos detected on the Earth's surface are difficult to understand and suggest that perhaps the composition of solar neutrinos oscillates between different neutrino types on their journey. In this way neutrinos originating in the Sun as electrontype could convert into heavy neutrinos, which could subsequently disintegrate into an electron-neutrino and a photon. In certain neutrino scenarios, such a photon would have an energy corresponding to that of visible light, and in principle should be detectable if there are enough of them. The problem is that they would normally be swamped by the copious photons of sunlight. The 24 October solar eclipse provided a chance to check this out. A team led by François Vannucci, spokesman of the Nomad neutrino experiment at CERN, en route to the 'Rencontres du Vietnam' physics meeting in Ho Chi Minh Ville, set up a CCD-equipped telescope. To insure against cloud cover, a second telescope followed the eclipse in the desert of Rajastan, India, where the eclipse was to last only half as long, but the chance of cloud was minimal. No background solar signal was seen, or, expressed in physics terms, if solar radiation has any heavy neutrino component, then less than a millionth of it disintegrates into an electron neutrino and a visible photon before it arrives at the Earth. The negative result also has implications for candidate massive, unstable neutrinos from other sources, notably a component of the missing 'dark matter' of the Universe. The next such eclipse should be visible in North Asia in 1997, when hopefully better measurements will be made

Solar neutrinos

International Nuclear Information System (INIS)

Phillips, R.J.N.

1987-09-01

The problem with solar neutrinos is that there seem to be too few of them, at least near the top end of the spectrum, since the 37 Cl detector finds only about 35% of the standard predicted flux. Various kinds of explanation have been offered: (a) the standard solar model is wrong, (b) neutrinos decay, (c) neutrinos have magnetic moments, (d) neutrinos oscillate. The paper surveys developments in each of these areas, especially the possible enhancement of neutrino oscillations by matter effects and adiabatic level crossing. The prospects for further independent experiments are also discussed. (author)

Search for Muon neutrino → Tau neutrino oscillations motivation and feasibility

International Nuclear Information System (INIS)

Zacek, V.

1988-01-01

Theoretical prejudices derived from solar-neutrino matter oscillations and assumptions of neutrino mass hierarchies suggest, that neutrino-oscillations are observable in laboratory with mass parameters of Δm 2 = 10 -3 -10 4 eV 2 . In particular Muon neutrino → Tau neutrino appearance searches at accelerators seem strongly motivated

Non-unitarity, sterile neutrinos, and non-standard neutrino interactions

Energy Technology Data Exchange (ETDEWEB)

Blennow, Mattias [Department of Theoretical Physics, School of Engineering Sciences, KTH Royal Institute of Technology, Albanova University Center, 106 91 Stockholm (Sweden); Coloma, Pilar [Theoretical Physics Department, Fermi National Accelerator Laboratory, P.O. Box 500, Batavia, IL 60510 (United States); Fernandez-Martinez, Enrique; Hernandez-Garcia, Josu [Departamento de Física Teórica, Universidad Autónoma de Madrid, Cantoblanco E-28049 Madrid (Spain); Instituto de Física Teórica UAM/CSIC, Calle Nicolás Cabrera 13-15, Cantoblanco E-28049 Madrid (Spain); Lopez-Pavon, Jacobo [INFN, Sezione di Genova, via Dodecaneso 33, 16146 Genova (Italy); CERN, Theoretical Physics Department, Geneva (Switzerland)

2017-04-27

The simplest Standard Model extension to explain neutrino masses involves the addition of right-handed neutrinos. At some level, this extension will impact neutrino oscillation searches. In this work we explore the differences and similarities between the case in which these neutrinos are kinematically accessible (sterile neutrinos) or not (mixing matrix non-unitarity). We clarify apparent inconsistencies in the present literature when using different parametrizations to describe these effects and recast both limits in the popular neutrino non-standard interaction (NSI) formalism. We find that, in the limit in which sterile oscillations are averaged out at the near detector, their effects at the far detector coincide with non-unitarity at leading order, even in presence of a matter potential. We also summarize the present bounds existing in both limits and compare them with the expected sensitivities of near-future facilities taking the DUNE proposal as a benchmark. We conclude that non-unitarity effects are too constrained to impact present or near future neutrino oscillation facilities but that sterile neutrinos can play an important role at long baseline experiments. The role of the near detector is also discussed in detail.

New neutrino physics and the altered shapes of solar neutrino spectra

Science.gov (United States)

Lopes, Ilídio

2017-01-01

Neutrinos coming from the Sun's core have been measured with high precision, and fundamental neutrino oscillation parameters have been determined with good accuracy. In this work, we estimate the impact that a new neutrino physics model, the so-called generalized Mikheyev-Smirnov-Wolfenstein (MSW) oscillation mechanism, has on the shape of some of leading solar neutrino spectra, some of which will be partially tested by the next generation of solar neutrino experiments. In these calculations, we use a high-precision standard solar model in good agreement with helioseismology data. We found that the neutrino spectra of the different solar nuclear reactions of the pp chains and carbon-nitrogen-oxygen cycle have quite distinct sensitivities to the new neutrino physics. The He P and 8B neutrino spectra are the ones in which their shapes are more affected when neutrinos interact with quarks in addition to electrons. The shapes of the 15O and 17F neutrino spectra are also modified, although in these cases the impact is much smaller. Finally, the impact in the shapes of the P P and 13N neutrino spectra is practically negligible.

Medidas Explícitas e Implícitas de las Actitudes Hacia las Mujeres

Directory of Open Access Journals (Sweden)

Manuel Cárdenas

2009-01-01

Full Text Available El presente estudio tiene como objeto utilizar el IAT (Implicit Association Test para medir actitudes hacia las mujeres, de modo de comparar dichas evaluaciones de carácter automático con las obtenidas por medio de una medida explícita. Además, los participantes respondieron a un inventario de roles sexuales de modo de ver si los sujetos manejaban el estereotipo dominante asociado a lo femenino y sus efectos sobre el prejuicio. La muestra quedó conformada por 80 estudiantes universitarios. No se detectaron diferencias significativas entre hombres y mujeres en los estereotipos asociados a la mujer, ni en la evaluación que se hace de estas (medida explícita. En la medida de IAT las diferencias entre sexos aparecen, indicando que los hombres muestran una actitud implícita más negativa hacia las mujeres. De este modo se confirma que la aparente disminución del prejuicio que puede constatarse en los cuestionarios podría encubrir el hecho de que las actitudes negativas se mantienen a nivel implícito.

Solar neutrino observations and neutrino oscillations

International Nuclear Information System (INIS)

Kuo, T.K.; Pantaleone, J.

1990-01-01

The results of recent Kamiokande-II and 37 Cl solar-neutrino experiments are quantitatively analyzed assuming the Mikheyev-Smirnov-Wolfenstein solution to the solar-neutrino problem. It is found that the parameter region known as the ''large mass'' solution to the solar-neutrino problem is disfavored by a little more than 1 σ while the ''small mass'' and ''large angle'' solutions are in good agreement at this level. The implications on this analysis from time variations in the data are discussed

JUNO. Determination of the neutrino mass hierarchy using reactor neutrinos

Energy Technology Data Exchange (ETDEWEB)

Wonsak, Bjoern [Hamburg University, Inst. Exp. Phys., Hamburg (Germany)

2015-07-01

The Jiangmen Underground Neutrino Observatory (JUNO) is a medium-baseline reactor neutrino experiment located in China. Its aim is to determine the neutrino mass hierarchy at more than 3 sigma significance after six years of data taking by using a 20kt liquid scintillator detector. To achieve this goal, an energy resolution of less than 3%/√(E) is necessary, creating strict requirements on the detector design and the liquid scintillator. Moreover, JUNO will be the only experiment in the near future able to measure the solar mixing parameters with a precision of better than 1%. This is at the same level as our current knowledge on flavour mixing in the quark sector, marking an important milestone of neutrino physics. In addition, supernova neutrinos, geo-neutrinos, sterile neutrinos as well as solar and atmospheric neutrinos can be studied. JUNO was approved in 2013 and the construction of the underground facility started early this year. In this talk the status of the experiment and its prospects is discussed.

Neutrino GDR meeting

International Nuclear Information System (INIS)

Aguilar-Saavedra, J.A.; Camilleri, L.; Mention, G.; VanElewyck, V.; Verderi, M.; Blondel, A.; Augier, C.; Bellefon, A. de; Coc, A.; Duchesneau, D.; Favier, J.; Lesgourgues, J.; Payet, J.

2006-01-01

The purpose of the neutrino GDR (research program coordination) is to federate the activities of French research teams devoted to studying the neutrino. The presentations have been organized on 2 days. A review of the present status of the theoretical and experimental knowledge on neutrinos on a worldwide basis has been made on the first day while the second day has been dedicated to reporting the activities of the 5 following working groups: 1) determination of neutrino parameters, 2) physics beyond the standard model, 3) neutrinos in the universe, 4) neutrino detection, and 5) common tools. During the first day the American neutrino research program has been presented through the description of the 2 neutrino detection systems: Nova and Minor. The following neutrino experiments involving nuclear reactors: Chooz (France), Daya-bay (China), Reno (Korea) and Angra (Brazil) have also been reviewed. This document is made up of the slides of the presentations

Probing the nature of the neutrino: The boron solar-neutrino experiment

International Nuclear Information System (INIS)

Raghavan, R.S.; Pakvasa, S.

1988-01-01

With a welter of neutrino scenarios and uncertain solar models to be unraveled, can solar-neutrino experiments really break new ground in neutrino physics? A new solar-neutrino detector BOREX, based on the nuclide /sup 11/B, promises the tools for a definitive exploration of the nature of the neutrino and the structure of the Sun. Using double-mode detection by neutrino excitation of /sup 11/B via the neutral-weak-current- and the charged-current-mediated inverse β decay in the same target, independent measurements of the total neutrino flux regardless of flavor and the survival of electron neutrinos in solar matter and a vacuum can be made. Standard models of the Sun, and almost every proposed nonstandard model of the neutrino, can be subjected to sharp and direct tests. The development of BOREX, based on B-loaded liquid-scintillation techniques, is currently in progress

Medida de la dureza de sólidos mediante nanoindentación

Directory of Open Access Journals (Sweden)

Alkorta, J.

2005-10-01

Full Text Available Hardness is not readily measurable by means of instrumented indentation since the value of the contact area depends on the pile-up or sink-in occurring near the contact surface of the sample. The most widespread method to estimate it by means of the loading/unloading curve of indentation, Oliver and Pharr’s method, deviates, in the extreme cases, up to a 25% from the real values since it only takes into account the elastic deflection. In this work, a new correction based on Oliver and Pharr’s method is proposed that agrees with the numerical calculations. Plastic hardening behaviour of the sample must be known to accurately estimate the contact area.

La medida de la dureza mediante indentación con registro de carga y desplazamiento no es evidente, dada la incertidumbre sobre el tamaño de huella debido al levantamiento (pile-up o hundimiento (sink-in plásticos de la superficie de la muestra alrededor del indentador. El método más utilizado para la medida de la dureza mediante la curva de carga/descarga de indentación, el de Oliver y Pharr, sólo tiene en cuenta hundimiento elástico, por lo que el error en la medida de la dureza y el módulo de Young puede llegar hasta un 25% en los casos más extremos. En el presente trabajo se discute una posible corrección al método de Oliver y Pharr para una obtención más ajustada del área de contacto de la huella. Esta corrección requiere de un conocimiento a priori o a posteriori del comportamiento plástico del material.

Neutrino Physics

CERN Document Server

Barenboim, G.

2014-12-10

The Standard Model has been incredibly successful in predicting the outcome of almost all the experiments done up so far. In it, neutrinos are mass-less. However, in recent years we have accumulated evidence pointing to tiny masses for the neutrinos (as compared to the charged leptons). These masses allow neutrinos to change their flavour and oscillate. In these lectures I review the properties of neutrinos in and beyond the Standard Model.

Neutrino masses and oscillations

Energy Technology Data Exchange (ETDEWEB)

Smirnov, A Yu

1996-11-01

New effects related to refraction of neutrinos in different media are reviewed and implication of the effects to neutrino mass and mixing are discussed. Patterns of neutrino masses and mixing implied by existing hints/bounds are described. Recent results on neutrino mass generation are presented. They include neutrino masses in SO(10) GUT`s and models with anomalous U(1), generation of neutrino mass via neutrino-neutralino mixing, models of sterile neutrino. (author). 95 refs, 9 figs.

Phenomenology of neutrino oscillations at the neutrino factory

International Nuclear Information System (INIS)

Tang, Jian

2011-01-01

We consider the prospects for a neutrino factory measuring mixing angles, the CP violating phase and mass-squared differences by detecting wrong-charge muons arising from the chain μ + → ν e → ν μ → μ - and the right-charge muons coming from the chain μ + → anti ν μ → anti ν μ → μ - (similar to μ - chains), where ν e → ν μ and anti ν μ → anti ν μ are neutrino oscillation channels through a long baseline. First, we study physics with near detectors and consider the treatment of systematic errors including cross section errors, flux errors, and background uncertainties. We illustrate for which measurements near detectors are required, discuss how many are needed, and what the role of the flux monitoring is. We demonstrate that near detectors are mandatory for the leading atmospheric parameter measurements if the neutrino factory has only one baseline, whereas systematic errors partially cancel if the neutrino factory complex includes the magic baseline. Second, we perform the baseline and energy optimization of the neutrino factory including the latest simulation results from the magnetized iron neutrino detector (MIND). We also consider the impact of τ decays, generated by appearance channels ν μ → ν τ and ν e → ν τ , on the discovery reaches of the mass orderings, the leptonic CP violation, and the non-zero θ 13 , which we find to be negligible for the considered detector. Third, we make a comparison of a high energy neutrino factory to a low energy neutrino factory and find that they are just two versions of the same experiment optimized for different regions of the parameter space. In addition, we briefly comment on whether it is useful to build the bi-magic baseline at the low energy neutrino factory. Finally, the effects of one additional massive sterile neutrino are discussed in the context of a combined short and long baseline setup. It is found that near detectors can provide the required sensitivity at the

Three neutrino flavors: Oscillations, mixing, and the solar-neutrino problem

International Nuclear Information System (INIS)

Pantaleone, J.

1991-01-01

An analytical, quantitative description of solar-neutrino propagation is presented which includes three flavors, matter dependence, and long-wavelength effects. Using the derived expression for the electron-neutrino survival probability, it is demonstrated that mixing is possible between the two-flavor Mikheyev-Smirnov-Wolfenstein and two-flavor long-wavelength solutions to the solar-neutrino problem. However, adiabatic conversion of a neutrino mass eigenstate tends to suppress all subsequent long-wavelength effects such as ''seasonal'' variations in the solar-neutrino flux

Sudbury Neutrino Observatory

International Nuclear Information System (INIS)

Beier, E.W.

1992-03-01

This document is a technical progress report on work performed at the University of Pennsylvania during the current year on the Sudbury Neutrino Observatory project. The motivation for the experiment is the measurement of neutrinos emitted by the sun. The Sudbury Neutrino Observatory (SNO) is a second generation dedicated solar neutrino experiment which will extend the results of our work with the Kamiokande II detector by measuring three reactions of neutrinos rather than the single reaction measured by the Kamiokande experiment. The collaborative project includes physicists from Canada, the United Kingdom, and the United States. Full funding for the construction of this facility was obtained in January 1990, and its construction is estimated to take five years. The motivation for the SNO experiment is to study the fundamental properties of neutrinos, in particular the mass and mixing parameters, which remain undetermined after decades of experiments in neutrino physics utilizing accelerators and reactors as sources of neutrinos. To continue the study of neutrino properties it is necessary to use the sun as a neutrino source. The long distance to the sun makes the search for neutrino mass sensitive to much smaller mass than can be studied with terrestrial sources. Furthermore, the matter density in the sun is sufficiently large to enhance the effects of small mixing between electron neutrinos and mu or tau neutrinos. This experiment, when combined with the results of the radiochemical 37 Cl and 71 Ga experiments and the Kamiokande II experiment, should extend our knowledge of these fundamental particles, and as a byproduct, improve our understanding of energy generation in the sun

Resonant spin-flavor precession of neutrino and the solar neutrino problem

International Nuclear Information System (INIS)

Akhmedov, E.Kh.; Bychuk, O.V.; AN SSSR, Moscow

1989-01-01

Resonant amplification of spin-flavor precession of neutrinos in solar matter is considered. Some possible consequences of the process are discussed. It is shown that resonant spin-flavor neutrino precession may account for the deficit of solar neutrinos in Davis' experiment and the anticorrelation between the rate of neutrino counting and solar activity. Experiments are considered which should make it possible to distinguish between spin-flavor neutrino precession and the Mikheyev-Smirnov-Wolfenstein effect. A new restriction on the usual spin precession of solar neutrinos is derived

Neutrino Physics at Drexel

Energy Technology Data Exchange (ETDEWEB)

Lane, Charles [Drexel Univ., Philadelphia, PA (United States); Dolinski, Michelle [Drexel Univ., Philadelphia, PA (United States); Neilson, Russell [Drexel Univ., Philadelphia, PA (United States)

2017-07-11

Our primary goal is to improve the understanding of the properties and interactions of neutrinos. We are pursuing this by means of the DUNE long-baseline and PROSPECT short-baseline neutrino experiments. For DUNE, a neutrino beam from Fermilab will be detected at the SURF facility in South Dakota, with the aim of determining the neutrino mass hierarchy (the mass ordering of neutrino flavors), and a measurement or limit on CP-violation via neutrinos. Our near-term experimental goal is to improve the characterization of the neutrino beam by measurements of muons produced as a byproduct of neutrino beam generation, to quantify the beam composition and flux. The short-range neutrino program has the aim of using the HFIR reactor at Oak Ridge as a neutrino source, with a detector placed nearby to find if there are short-distance oscillations to sterile neutrino flavors, and to resolve the 'reactor neutrino spectral anomaly' which has shown up as an unexplained 'bump' in the neutrino energy spectrum in recent experiments.

Massive neutrinos flavor mixing of leptons and neutrino oscillations

CERN Document Server

2015-01-01

Since the discovery of neutrino oscillations neutrino physics has become an interesting field of research in physics. They imply that neutrino must have a small mass and that the neutrinos, coupled to the charged leptons, are mixtures of the mass eigenstates, analogous to the flavor mixing of the quarks. The mixing angles for the quarks are small, but for the leptons two of the mixing angles are large. The masses of the three neutrinos must be very small, less than 1 eV, but from the oscillation experiments we only know the mass differences — the absolute masses are still unknown. Also we do not know, if the masses of the neutrinos are Dirac masses, as the masses of the charged leptons and of the quarks, or whether they are Majorana masses. In this volume, an overview of the present state of research in neutrino physics is given by well-known experimentalists and theorists. The contents — originated from talks and discussions at a recent conference addressing some of the most pressing open questions in n...

Dois pesos e duas medidas: uma proposta para discutir a natureza do sistema de unidades de medida na sala de aula

Directory of Open Access Journals (Sweden)

Lidiany C. de O. Godoi

2009-01-01

Full Text Available http://dx.doi.org/10.5007/2175-7941.2008v25n3p523 Sugerimos neste artigo um plano de ensino que, envolvendo um trabalho interdisciplinar, discuta a natureza do Sistema de Unidades de Medida. Por meio de dinâmicas de grupos, leitura e interpretação de textos históricos, poemas e ilustrações e também através de outras fontes, acreditamos ser possível mostrar que o sistema de unidades de medida adotado atualmente (SI não é um dado natural, mas o resultado de um processo histórico de negociação de significados e, portanto, contingente das relações sociais. A partir da perspectiva dos Estudos Sociais da Ciência (ou Nova História e Sociologia do Conhecimento, apresentamos algumas discussões que envolveram a adoção do Sistema Decimal na França, bem como as dificuldades de sua posterior implementação no Brasil, expressa pela Revolta do Quebra-Quilos. Esperamos que as dinâmicas sugeridas neste trabalho possibilitem aos estudantes reconhecerem a si mesmos como participantes do processo de construção do conhecimento científico através da observação diária das mudanças que conferem novas feições a ele e também da tentativa de tornar mais significativo um tópico do currículo que, muitas vezes, é considerado desinteressante, enfadonho ou simples memorização de grandezas e de suas conversões.

The Intermediate Neutrino Program

CERN Document Server

Adams, C.; Ankowski, A.M.; Asaadi, J.A.; Ashenfelter, J.; Axani, S.N.; Babu, K.; Backhouse, C.; Band, H.R.; Barbeau, P.S.; Barros, N.; Bernstein, A.; Betancourt, M.; Bishai, M.; Blucher, E.; Bouffard, J.; Bowden, N.; Brice, S.; Bryan, C.; Camilleri, L.; Cao, J.; Carlson, J.; Carr, R.E.; Chatterjee, A.; Chen, M.; Chen, S.; Chiu, M.; Church, E.D.; Collar, J.I.; Collin, G.; Conrad, J.M.; Convery, M.R.; Cooper, R.L.; Cowen, D.; Davoudiasl, H.; de Gouvea, A.; Dean, D.J.; Deichert, G.; Descamps, F.; DeYoung, T.; Diwan, M.V.; Djurcic, Z.; Dolinski, M.J.; Dolph, J.; Donnelly, B.; Dwyer, D.A.; Dytman, S.; Efremenko, Y.; Everett, L.L.; Fava, A.; Figueroa-Feliciano, E.; Fleming, B.; Friedland, A.; Fujikawa, B.K.; Gaisser, T.K.; Galeazzi, M.; Galehouse, D.C.; Galindo-Uribarri, A.; Garvey, G.T.; Gautam, S.; Gilje, K.E.; Gonzalez-Garcia, M.; Goodman, M.C.; Gordon, H.; Gramellini, E.; Green, M.P.; Guglielmi, A.; Hackenburg, R.W.; Hackenburg, A.; Halzen, F.; Han, K.; Hans, S.; Harris, D.; Heeger, K.M.; Herman, M.; Hill, R.; Holin, A.; Huber, P.; Jaffe, D.E.; Johnson, R.A.; Joshi, J.; Karagiorgi, G.; Kaufman, L.J.; Kayser, B.; Kettell, S.H.; Kirby, B.J.; Klein, J.R.; Kolomensky, Yu. G.; Kriske, R.M.; Lane, C.E.; Langford, T.J.; Lankford, A.; Lau, K.; Learned, J.G.; Ling, J.; Link, J.M.; Lissauer, D.; Littenberg, L.; Littlejohn, B.R.; Lockwitz, S.; Lokajicek, M.; Louis, W.C.; Luk, K.; Lykken, J.; Marciano, W.J.; Maricic, J.; Markoff, D.M.; Martinez Caicedo, D.A.; Mauger, C.; Mavrokoridis, K.; McCluskey, E.; McKeen, D.; McKeown, R.; Mills, G.; Mocioiu, I.; Monreal, B.; Mooney, M.R.; Morfin, J.G.; Mumm, P.; Napolitano, J.; Neilson, R.; Nelson, J.K.; Nessi, M.; Norcini, D.; Nova, F.; Nygren, D.R.; Orebi Gann, G.D.; Palamara, O.; Parsa, Z.; Patterson, R.; Paul, P.; Pocar, A.; Qian, X.; Raaf, J.L.; Rameika, R.; Ranucci, G.; Ray, H.; Reyna, D.; Rich, G.C.; Rodrigues, P.; Romero, E.Romero; Rosero, R.; Rountree, S.D.; Rybolt, B.; Sanchez, M.C.; Santucci, G.; Schmitz, D.; Scholberg, K.; Seckel, D.; Shaevitz, M.; Shrock, R.; Smy, M.B.; Soderberg, M.; Sonzogni, A.; Sousa, A.B.; Spitz, J.; St. John, J.M.; Stewart, J.; Strait, J.B.; Sullivan, G.; Svoboda, R.; Szelc, A.M.; Tayloe, R.; Thomson, M.A.; Toups, M.; Vacheret, A.; Vagins, M.; Van de Water, R.G.; Vogelaar, R.B.; Weber, M.; Weng, W.; Wetstein, M.; White, C.; White, B.R.; Whitehead, L.; Whittington, D.W.; Wilking, M.J.; Wilson, R.J.; Wilson, P.; Winklehner, D.; Winn, D.R.; Worcester, E.; Yang, L.; Yeh, M.; Yokley, Z.W.; Yoo, J.; Yu, B.; Yu, J.; Zhang, C.

2015-01-01

The US neutrino community gathered at the Workshop on the Intermediate Neutrino Program (WINP) at Brookhaven National Laboratory February 4-6, 2015 to explore opportunities in neutrino physics over the next five to ten years. Scientists from particle, astroparticle and nuclear physics participated in the workshop. The workshop examined promising opportunities for neutrino physics in the intermediate term, including possible new small to mid-scale experiments, US contributions to large experiments, upgrades to existing experiments, R&D plans and theory. The workshop was organized into two sets of parallel working group sessions, divided by physics topics and technology. Physics working groups covered topics on Sterile Neutrinos, Neutrino Mixing, Neutrino Interactions, Neutrino Properties and Astrophysical Neutrinos. Technology sessions were organized into Theory, Short-Baseline Accelerator Neutrinos, Reactor Neutrinos, Detector R&D and Source, Cyclotron and Meson Decay at Rest sessions.This report summ...

Underground neutrino astronomy

International Nuclear Information System (INIS)

Schramm, D.N.

1983-02-01

A review is made of possible astronomical neutrino sources detectable with underground facilities. Comments are made about solar neutrinos and gravitational-collapse neutrinos, and particular emphasis is placed on ultra-high-energy astronomical neutrino sources. An appendix mentions the exotic possibility of monopolonium

Neutrinos: Theory and Phenomenology

Energy Technology Data Exchange (ETDEWEB)

Parke, Stephen

2013-10-22

The theory and phenomenology of neutrinos will be addressed, especially that relating to the observation of neutrino flavor transformations. The current status and implications for future experiments will be discussed with special emphasis on the experiments that will determine the neutrino mass ordering, the dominant flavor content of the neutrino mass eigenstate with the smallest electron neutrino content and the size of CP violation in the neutrino sector. Beyond the neutrino Standard Model, the evidence for and a possible definitive experiment to confirm or refute the existence of light sterile neutrinos will be briefly discussed.

Search for sterile neutrinos at a new short-baseline CERN neutrino beam

International Nuclear Information System (INIS)

Mauri, N.

2014-01-01

In the last few years the experimental results on neutrino/anti-neutrino oscillations at Short-Baseline (SBL) showed a tension with several phenomenological models. The recent and carefully recomputed anti-neutrino fluxes from nuclear reactors have further increased this tension drawing a picture not fully compatible with the 3 neutrino oscillation scenario. A sterile neutrino is a neutral lepton which does not couple with W/Z bosons. it is not an exotic particle, its existence being a natural consequence of neutrinos having a non-zero mass. Sterile neutrinos can mix with the active ones through additional mass eigenstates, with no necessary mass scale. We will present an experimental search for sterile neutrinos with a new CERN-SPS neutrino beam using muon spectrometers and large LAr detectors. To definitely clarify the physics issue, the proposed experiment will study oscillations in a muon neutrino / antineutrino beam both in appearance and disappearance modes, exploring the Δm 2 ∼ 1 eV 2 range

The Intermediate Neutrino Program

Energy Technology Data Exchange (ETDEWEB)

Adams, C.; et al.

2015-03-23

The US neutrino community gathered at the Workshop on the Intermediate Neutrino Program (WINP) at Brookhaven National Laboratory February 4-6, 2015 to explore opportunities in neutrino physics over the next five to ten years. Scientists from particle, astroparticle and nuclear physics participated in the workshop. The workshop examined promising opportunities for neutrino physics in the intermediate term, including possible new small to mid-scale experiments, US contributions to large experiments, upgrades to existing experiments, R&D plans and theory. The workshop was organized into two sets of parallel working group sessions, divided by physics topics and technology. Physics working groups covered topics on Sterile Neutrinos, Neutrino Mixing, Neutrino Interactions, Neutrino Properties and Astrophysical Neutrinos. Technology sessions were organized into Theory, Short-Baseline Accelerator Neutrinos, Reactor Neutrinos, Detector R&D and Source, Cyclotron and Meson Decay at Rest sessions.This report summarizes discussion and conclusions from the workshop.

The Intermediate Neutrino Program

Energy Technology Data Exchange (ETDEWEB)

Adams, C. [Yale Univ., New Haven, CT (United States); Alonso, J. R. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Ankowski, A. M. [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States); Asaadi, J. A. [Syracuse Univ., NY (United States); Ashenfelter, J. [Yale Univ., New Haven, CT (United States); Axani, S. N. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Babu, K [Oklahoma State Univ., Stillwater, OK (United States); Backhouse, C. [California Inst. of Technology (CalTech), Pasadena, CA (United States); Band, H. R. [Yale Univ., New Haven, CT (United States); Barbeau, P. S. [Duke Univ., Durham, NC (United States); Barros, N. [Univ. of Pennsylvania, Philadelphia, PA (United States); Bernstein, A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Betancourt, M. [Illinois Inst. of Technology, Chicago, IL (United States); Bishai, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Blucher, E. [Univ. of Chicago, IL (United States); Bouffard, J. [State Univ. of New York (SUNY), Albany, NY (United States); Bowden, N. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Brice, S. [Illinois Inst. of Technology, Chicago, IL (United States); Bryan, C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Camilleri, L. [Columbia Univ., New York, NY (United States); Cao, J. [Inst. of High Energy Physics, Beijing (China); Carlson, J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Carr, R. E. [Columbia Univ., New York, NY (United States); Chatterjee, A. [Univ. of Texas, Arlington, TX (United States); Chen, M. [Univ. of California, Irvine, CA (United States); Chen, S. [Tsinghua Univ., Beijing (China); Chiu, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Church, E. D. [Illinois Inst. of Technology, Chicago, IL (United States); Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Collar, J. I. [Univ. of Chicago, IL (United States); Collin, G. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Conrad, J. M. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Convery, M. R. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Cooper, R. L. [Indiana Univ., Bloomington, IN (United States); Cowen, D. [Pennsylvania State Univ., University Park, PA (United States); Davoudiasl, H. [Brookhaven National Lab. (BNL), Upton, NY (United States); Gouvea, A. D. [Northwestern Univ., Evanston, IL (United States); Dean, D. J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Deichert, G. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Descamps, F. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); DeYoung, T. [Michigan State Univ., East Lansing, MI (United States); Diwan, M. V. [Brookhaven National Lab. (BNL), Upton, NY (United States); Djurcic, Z. [Argonne National Lab. (ANL), Argonne, IL (United States); Dolinski, M. J. [Drexel Univ., Philadelphia, PA (United States); Dolph, J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Donnelly, B. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Dwyer, D. A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Dytman, S. [Univ. of Pittsburgh, PA (United States); Efremenko, Y. [Univ. of Tennessee, Knoxville, TN (United States); Everett, L. L. [Univ. of Wisconsin, Madison, WI (United States); Fava, A. [University of Padua, Padova (Italy); Figueroa-Feliciano, E. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Fleming, B. [Yale Univ., New Haven, CT (United States); Friedland, A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Fujikawa, B. K. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Gaisser, T. K. [Univ. of Delaware, Newark, DE (United States); Galeazzi, M. [Univ. of Miami, FL (United States); Galehouse, DC [Univ. of Akron, OH (United States); Galindo-Uribarri, A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Garvey, G. T. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Gautam, S. [Tribhuvan Univ., Kirtipur (Nepal); Gilje, K. E. [Illinois Inst. of Technology, Chicago, IL (United States); Gonzalez-Garcia, M. [Stony Brook Univ., NY (United States); Goodman, M. C. [Argonne National Lab. (ANL), Argonne, IL (United States); Gordon, H. [Brookhaven National Lab. (BNL), Upton, NY (United States); Gramellini, E. [Yale Univ., New Haven, CT (United States); Green, M. P. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Guglielmi, A. [University of Padua, Padova (Italy); Hackenburg, R. W. [Brookhaven National Lab. (BNL), Upton, NY (United States); Hackenburg, A. [Yale Univ., New Haven, CT (United States); Halzen, F. [Univ. of Wisconsin, Madison, WI (United States); Han, K. [Yale Univ., New Haven, CT (United States); Hans, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Harris, D. [Illinois Inst. of Technology, Chicago, IL (United States); Heeger, K. M. [Yale Univ., New Haven, CT (United States); Herman, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Hill, R. [Univ. of Chicago, IL (United States); Holin, A. [Univ. College London, Bloomsbury (United Kingdom); Huber, P. [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States); Jaffe, D. E. [Brookhaven National Lab. (BNL), Upton, NY (United States); Johnson, R. A. [Univ. of Cincinnati, OH (United States); Joshi, J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Karagiorgi, G. [Univ. of Manchester (United Kingdom); Kaufman, L. J. [Indiana Univ., Bloomington, IN (United States); Kayser, B. [Illinois Inst. of Technology, Chicago, IL (United States); Kettell, S. H. [Brookhaven National Lab. (BNL), Upton, NY (United States); Kirby, B. J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Klein, J. R. [Univ. of Texas, Arlington, TX (United States); Kolomensky, Y. G. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of California, Berkeley, CA (United States); Kriske, R. M. [Univ. of Minnesota, Minneapolis, MN (United States); Lane, C. E. [Drexel Univ., Philadelphia, PA (United States); Langford, T. J. [Yale Univ., New Haven, CT (United States); Lankford, A. [Univ. of California, Irvine, CA (United States); Lau, K. [Univ. of Houston, TX (United States); Learned, J. G. [Univ. of Hawaii, Honolulu, HI (United States); Ling, J. [Univ. of Illinois, Urbana-Champaign, IL (United States); Link, J. M. [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States); Lissauer, D. [Brookhaven National Lab. (BNL), Upton, NY (United States); Littenberg, L. [Brookhaven National Lab. (BNL), Upton, NY (United States); Littlejohn, B. R. [Illinois Inst. of Technology, Chicago, IL (United States); Lockwitz, S. [Illinois Inst. of Technology, Chicago, IL (United States); Lokajicek, M. [Inst. of Physics of the Academy of Sciences of Czech Republic, Prague (Czech Republic); Louis, W. C. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Luk, K. [Univ. of California, Berkeley, CA (United States); Lykken, J. [Illinois Inst. of Technology, Chicago, IL (United States); Marciano, W. J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Maricic, J. [Univ. of Hawaii, Honolulu, HI (United States); Markoff, D. M. [North Carolina Central Univ., Durham, NC (United States); Caicedo, D. A. M. [Illinois Inst. of Technology, Chicago, IL (United States); Mauger, C. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Mavrokoridis, K. [Univ. of Liverpool (United Kingdom); McCluskey, E. [Illinois Inst. of Technology, Chicago, IL (United States); McKeen, D. [Univ. of Washington, Seattle, WA (United States); McKeown, R. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Mills, G. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Mocioiu, I. [Pennsylvania State Univ., University Park, PA (United States); Monreal, B. [Univ. of California, Santa Barbara, CA (United States); Mooney, M. R. [Brookhaven National Lab. (BNL), Upton, NY (United States); Morfin, J. G. [Illinois Inst. of Technology, Chicago, IL (United States); Mumm, P. [National Inst. of Standards and Technology (NIST), Boulder, CO (United States); Napolitano, J. [Temple Univ., Philadelphia, PA (United States); Neilson, R. [Drexel Univ., Philadelphia, PA (United States); Nelson, J. K. [College of William and Mary, Williamsburg, VA (United States); Nessi, M. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Norcini, D. [Yale Univ., New Haven, CT (United States); Nova, F. [Univ. of Texas, Austin, TX (United States); Nygren, D. R. [Univ. of Texas, Arlington, TX (United States); Gann, GDO [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of California, Berkeley, CA (United States); Palamara, O. [Illinois Inst. of Technology, Chicago, IL (United States); Parsa, Z. [Brookhaven National Lab. (BNL), Upton, NY (United States); Patterson, R. [California Inst. of Technology (CalTech), Pasadena, CA (United States); Paul, P. [Stony Brook Univ., NY (United States); Pocar, A. [Univ. of Massachusetts, Amherst, MA (United States); Qian, X. [Brookhaven National Lab. (BNL), Upton, NY (United States); Raaf, J. L. [Illinois Inst. of Technology, Chicago, IL (United States); Rameika, R. [Illinois Inst. of Technology, Chicago, IL (United States); Ranucci, G. [National Inst. of Nuclear Physics, Milano (Italy); Ray, H. [Univ. of Florida, Gainesville, FL (United States); Reyna, D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Rich, G. C. [Triangle Universities Nuclear Lab., Durham, NC (United States); Rodrigues, P. [Univ. of Rochester, NY (United States); Romero, E. R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Univ. of Tennessee, Knoxville, TN (United States); Rosero, R. [Brookhaven National Lab. (BNL), Upton, NY (United States); Rountree, S. D. [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States); Rybolt, B. [Univ. of Tennessee, Knoxville, TN (United States); Sanchez, M. C. [Iowa State Univ., Ames, IA (United States); Santucci, G. [Stony Brook Univ., NY (United States); Schmitz, D. [Univ. of Chicago, IL (United States); Scholberg, K. [Duke Univ., Durham, NC (United States); Seckel, D. [Univ. of Delaware, Newark, DE (United States); Shaevitz, M. [Columbia Univ., New York, NY (United States); Shrock, R. [Stony Brook Univ., NY (United States); Smy, M. B. [Univ. of California, Irvine, CA (United States); Soderberg, M. [Syracuse Univ., NY (United States); Sonzogni, A. [Brookhaven National Lab. (BNL), Upton, NY (United States); Sousa, A. B. [Univ. of Cincinnati, OH (United States); Spitz, J. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); John, J. M. S. [Univ. of Cincinnati, OH (United States); Stewart, J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Strait, J. B. [Illinois Inst. of Technology, Chicago, IL (United States); Sullivan, G. [Univ. of Maryland, College Park, MD (United States); Svoboda, R. [Univ. of California, Davis, CA (United States); Szelc, A. M. [Yale Univ., New Haven, CT (United States); Tayloe, R. [Indiana Univ., Bloomington, IN (United States); Thomson, M. A. [Univ. of Cambridge (United Kingdom); Toups, M. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Vacheret, A. [Univ. of Oxford (United Kingdom); Vagins, M. [Univ. of California, Irvine, CA (United States); Water, R. G. V. D. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Vogelaar, R. B. [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States); Weber, M. [Bern (Switzerland); Weng, W. [Brookhaven National Lab. (BNL), Upton, NY (United States); Wetstein, M. [Univ. of Chicago, IL (United States); White, C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); White, B. R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Whitehead, L. [Univ. of Houston, TX (United States); Whittington, D. W. [Indiana Univ., Bloomington, IN (United States); Wilking, M. J. [Stony Brook Univ., NY (United States); Wilson, R. J. [Colorado State Univ., Fort Collins, CO (United States); Wilson, P. [Illinois Inst. of Technology, Chicago, IL (United States); Winklehner, D. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Winn, D. R. [Fairfield Univ., CT (United States); Worcester, E. [Brookhaven National Lab. (BNL), Upton, NY (United States); Yang, L. [Univ. of Illinois, Urbana-Champaign, IL (United States); Yeh, M [Brookhaven National Lab. (BNL), Upton, NY (United States); Yokley, Z. W. [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States); Yoo, J. [Illinois Inst. of Technology, Chicago, IL (United States); Yu, B. [Brookhaven National Lab. (BNL), Upton, NY (United States); Yu, J. [Univ. of Texas, Arlington, TX (United States); Zhang, C. [Brookhaven National Lab. (BNL), Upton, NY (United States)

2017-04-03

The US neutrino community gathered at the Workshop on the Intermediate Neutrino Program (WINP) at Brookhaven National Laboratory February 4-6, 2015 to explore opportunities in neutrino physics over the next five to ten years. Scientists from particle, astroparticle and nuclear physics participated in the workshop. The workshop examined promising opportunities for neutrino physics in the intermediate term, including possible new small to mid-scale experiments, US contributions to large experiments, upgrades to existing experiments, R&D plans and theory. The workshop was organized into two sets of parallel working group sessions, divided by physics topics and technology. Physics working groups covered topics on Sterile Neutrinos, Neutrino Mixing, Neutrino Interactions, Neutrino Properties and Astrophysical Neutrinos. Technology sessions were organized into Theory, Short-Baseline Accelerator Neutrinos, Reactor Neutrinos, Detector R&D and Source, Cyclotron and Meson Decay at Rest sessions.This report summarizes discussion and conclusions from the workshop.

Geometric phase of neutrinos: Differences between Dirac and Majorana neutrinos

Science.gov (United States)

Capolupo, A.; Giampaolo, S. M.; Hiesmayr, B. C.; Vitiello, G.

2018-05-01

We analyze the non-cyclic geometric phase for neutrinos. We find that the geometric phase and the total phase associated to the mixing phenomenon provide a theoretical tool to distinguish between Dirac and Majorana neutrinos. Our results hold for neutrinos propagating in vacuum and through the matter. We feed the values of the experimental parameters in our formulas in order to make contact with experiments. Although it remains an open question how the geometric phase of neutrinos could be detected, our theoretical results may open new scenarios in the investigation of the neutrino nature.

The Neutrinos Saga

International Nuclear Information System (INIS)

La Souchere, Marie-Christine de; Moran, John

2009-04-01

The author proposes a history of the discovery and study of neutrinos. This history starts shortly after the discovery of radioactivity in 1896 with the observation of an inhomogeneous deceleration of electrons in the radioactive source which raised an issue of shortage of energy. Pauli then introduced the idea of a ghost particle which could preserve the principle of energy conservation and also the issue of statistics related to the laws of quantum mechanics. Works by the Joliot-Curies and Chadwick resulted in the identification of a neutral particle, first called a neutron, and then neutrino. The author then reports experiments performed to highlight neutrinos, and to identify different forms of neutrinos: muon, tau, lepton. She also addresses questions raised by solar neutrinos, experiments proving the metamorphosis of electron neutrinos into muon neutrinos. She discusses the interest of neutrino as cosmic messengers as they are emitted by various cosmic events, and also as a way to study dark matter

Identifying the neutrino mass hierarchy with supernova neutrinos

International Nuclear Information System (INIS)

Tomas, Ricard

2006-01-01

We review how a high-statistics observation of the neutrino signal from a future galactic core-collapse supernova (SN) may be used to discriminate between different neutrino mixing scenarios. We discuss two complementary methods that allow for the positive identification of the mass hierarchy without knowledge of the emitted neutrino fluxes, provided that the 13-mixing angle is large, sin 2 θ 13 -5 . These two approaches are the observation of modulations in the neutrino spectra by Earth matter effects or by the passage of shock waves through the SN envelope. If the value of the 13-mixing angle is unknown, using additionally the information encoded in the prompt neutronization ν e burst-a robust feature found in all modern SN simulations-can be sufficient to fix both the neutrino hierarchy and to decide whether θ 13 is 'small' or 'large'

Neutrinos (1/3)

CERN Multimedia

CERN. Geneva

2013-01-01

The neutrino, the lightest and most weakly interacting particle of the Standard Model has revealed itself as the messenger of very exciting news in particle physics: there is Physics Beyond the Standard Model. All this thanks to the quantum-mechanical phenomenon of flavour oscillations which is intrinsically connected to the question of neutrino mass and which has been observed in neutrinos produced in natural sources, like the Sun and the Earth's atmosphere, as well as with human made neutrino beams at accelerator and reactors. The purpose of these lectures is to overview some aspects of the phenomenology of massive neutrinos. I will present the simplest extensions for adding neutrino masses to the SM, and then I will describe the phenomenology associated with neutrino oscillations in vacuum and in matter and its present signatures.

Phenomenology of neutrino oscillations at the neutrino factory

Energy Technology Data Exchange (ETDEWEB)

Tang, Jian

2011-12-19

We consider the prospects for a neutrino factory measuring mixing angles, the CP violating phase and mass-squared differences by detecting wrong-charge muons arising from the chain {mu}{sup +} {yields} {nu}{sub e} {yields} {nu}{sub {mu}} {yields} {mu}{sup -} and the right-charge muons coming from the chain {mu}{sup +} {yields} anti {nu}{sub {mu}} {yields} anti {nu}{sub {mu}} {yields} {mu}{sup -} (similar to {mu}{sup -} chains), where {nu}{sub e} {yields} {nu}{sub {mu}} and anti {nu}{sub {mu}} {yields} anti {nu}{sub {mu}} are neutrino oscillation channels through a long baseline. First, we study physics with near detectors and consider the treatment of systematic errors including cross section errors, flux errors, and background uncertainties. We illustrate for which measurements near detectors are required, discuss how many are needed, and what the role of the flux monitoring is. We demonstrate that near detectors are mandatory for the leading atmospheric parameter measurements if the neutrino factory has only one baseline, whereas systematic errors partially cancel if the neutrino factory complex includes the magic baseline. Second, we perform the baseline and energy optimization of the neutrino factory including the latest simulation results from the magnetized iron neutrino detector (MIND). We also consider the impact of {tau} decays, generated by appearance channels {nu}{sub {mu}} {yields} {nu}{sub {tau}} and {nu}{sub e} {yields} {nu}{sub {tau}}, on the discovery reaches of the mass orderings, the leptonic CP violation, and the non-zero {theta}{sub 13}, which we find to be negligible for the considered detector. Third, we make a comparison of a high energy neutrino factory to a low energy neutrino factory and find that they are just two versions of the same experiment optimized for different regions of the parameter space. In addition, we briefly comment on whether it is useful to build the bi-magic baseline at the low energy neutrino factory. Finally, the

Medidas de conservación y ordenación pesquera del jurel Trachurus murphyien el Perú

Directory of Open Access Journals (Sweden)

Jorge Zuzunaga

2013-10-01

Full Text Available Las pesquerías peruanas como actividades realizadas sobre recursos naturales renovables son reguladas por un marco jurídico, cuyo objetivo es asegurar su conservación y uso sostenible. La Ley General de Pesca (DL N°. 25977 señala que para cada tipo de pesquería y según la situación del recurso explotado debe establecerse un sistema de ordenamiento que concilie el principio de sostenibilidad de los recursos pesqueros o conservación en el largo plazo, con la obtención de los mayores beneficios económicos y sociales. En el ordenamiento pesquero del jurel Trachurus murphyi, las medidas incluyen entre otras, el régimen de acceso constituido por las autorizaciones de incremento de flota y permisos de pesca, que se otorgan solo a los buques cuyas capturas son destinadas únicamente para el consumo humano directo, de acuerdo a lo dispuesto en el Reglamento de Ordenamiento Pesquero (DS N.° 011-2007-PRODUCE. La obligación de destinar los recursos sardina Sardinops sagax, jurel T. murphyiy caballa Scomber japonicus al consumo humano directo rige desde septiembre 2002 (DS N°. 001-2002-PRODUCE. Otras medidas vigentes restringen el tamaño mínimo de malla de las redes, prohíben la captura de ejemplares menores de 31 cm de longitud total, determinan el inicio y cierre de las temporadas de pesca, los límites de captura o cuotas anuales. Estas disposiciones son complementadas por medidas de seguimiento, control y vigilancia para la efectiva conservación y uso sostenido del recurso.

The neutrino mirror

International Nuclear Information System (INIS)

Vannucci, F.

2003-09-01

The neutrino is not an elementary particle like others, it is the most stunning of all: the neutrino is undetectable by itself, we have only indirect evidences of its existence, but the neutrino is essential to explain the weak interaction, to understand why matter triumphed over anti-matter just after the Big-bang, or to solve the riddle of the hidden mass of the universe. This book is a popular work dedicated to the neutrino from its discovery in beta decays to the most recent theories such as neutrino oscillations, and via the worldwide experiments dedicated to the study of the neutrinos. (A.C.)

Nuevo criterio de complejidad utilizando una medida de eficiencia

OpenAIRE

Munduate del Río, Arantza; Pérez Prados, Antonio; Cano Sevilla, Francisco J.

1995-01-01

Centrado en el campo de los árboles de decisión, este trabajo estudia la forma de selección de un árbol óptimo entre los posibles árbo1es obtenidos a partir del análisis de un conjunto de datos, utilizando para ello una cantidad criterio que combina linealmente dos medidas de la calidad de un árbol: el error de resustitución y la eficiencia. Analizando el efecto de un proceso de poda en la cantidad criterio se obtiene una sucesión finita de subárboles rnínimos óptimamente podados del árbol má...

The solar neutrino problem after the GALLEX artificial neutrino source experiment

International Nuclear Information System (INIS)

Vignaud, D.

1995-01-01

Using an intense 51 Cr artificial neutrino source (more than 60 PBq), the GALLEX solar neutrino collaboration has recently checked that its radiochemical detector was fully efficient for the detection of solar neutrinos. After this crucial result, the status of the solar neutrino problem is reviewed, with emphasis on how neutrino oscillations may explain (through the MSW effect) the different deficits observed in the four existing experiments. (author). 25 refs., 5 figs., 1 tab

Non-Unitarity, sterile neutrinos, and Non-Standard neutrino Interactions

CERN Document Server

Blennow, Mattias; Fernandez-Martinez, Enrique; Hernandez-Garcia, Josu; Lopez-Pavon, Jacobo

2017-04-27

The simplest Standard Model extension to explain neutrino masses involves the addition of right-handed neutrinos. At some level, this extension will impact neutrino oscillation searches. In this work we explore the differences and similarities between the case in which these neutrinos are kinematically accessible (sterile neutrinos) or not (mixing matrix non-unitarity). We clarify apparent inconsistencies in the present literature when using different parametrizations to describe these effects and recast both limits in the popular neutrino non-standard interaction (NSI) formal- ism. We find that, in the limit in which sterile oscillations are averaged out at the near detector, their effects at the far detector coincide with non-unitarity at leading order, even in presence of a matter potential. We also summarize the present bounds existing in both limits and compare them with the expected sensitivities of near-future facilities taking the DUNE proposal as a bench- mark. We conclude that non-unitarity effects ...

Neutrino oscillations and neutrino-electron scattering

International Nuclear Information System (INIS)

Kayser, B.; Rosen, S.P.

1980-10-01

Neutrino flavor oscillations can significantly alter the cross section for neutrino-electron scattering. As a result, such oscillations can affect the comparison between existing reactor data and theories of neutral-current processes. They may also lead to strikingly large effects in high-energy accelerator experiments

Sterile neutrinos beyond LSND at the neutrino factory

International Nuclear Information System (INIS)

Meloni, Davide; Tang Jian; Winter, Walter

2010-01-01

We discuss the effects of one additional sterile neutrino at the Neutrino Factory. Compared to earlier analyses, which have been motivated by Liquid Scintillator Neutrino Detector (LSND) results, we do not impose any constraint on the additional mass squared splitting. This means that the additional mass eigenstate could, with small mixings, be located among the known ones, as it is suggested by the recent analysis of cosmological data. We use a self-consistent framework at the Neutrino Factory without any constraints on the new parameters. We demonstrate for a combined short and long baseline setup that near detectors can provide the expected sensitivity at the LSND-motivated Δm 41 2 -range, while some sensitivity can also be obtained in the region of the atmospheric mass splitting from the long baselines. We point out that limits on such very light sterile neutrinos may also be obtained from a reanalysis of atmospheric and solar neutrino oscillation data, as well as from supernova neutrino observations. In the second part of the analysis, we compare our sensitivity with the existing literature using additional assumptions, such as |Δm 41 2 |>>|Δm 31 2 |, leading to averaging of the fast oscillations in the far detectors. We demonstrate that while the Neutrino Factory has excellent sensitivity compared to existing studies using similar assumptions, one has to be very careful interpreting these results for a combined short and long baseline setup where oscillations could occur in the near detectors. We also test the impact of additional ν τ detectors at the short and long baselines, and we do not find a substantial improvement of the sensitivities.

ABSOLUTE NEUTRINO MASSES

DEFF Research Database (Denmark)

Schechter, J.; Shahid, M. N.

2012-01-01

We discuss the possibility of using experiments timing the propagation of neutrino beams over large distances to help determine the absolute masses of the three neutrinos.......We discuss the possibility of using experiments timing the propagation of neutrino beams over large distances to help determine the absolute masses of the three neutrinos....

Workshop: Neutrino telescopes

International Nuclear Information System (INIS)

Anon.

1990-01-01

Despite being the most elusive of the known particles, neutrinos provide vital new physics insights. Most neutrino knowledge so far has come from studies using beams from reactors and accelerators, but in recent years important new contributions have resulted from investigation of natural neutrinos from cosmic rays, nearby stars (the sun), or distant sources, such as the 1987 supernova. The supernova observations marked the start of a new era in neutrino astronomy, but neutrino telescopes were anyway assured of an important ongoing role

Workshop: Neutrino telescopes

Energy Technology Data Exchange (ETDEWEB)

Anon.

1990-05-15

Despite being the most elusive of the known particles, neutrinos provide vital new physics insights. Most neutrino knowledge so far has come from studies using beams from reactors and accelerators, but in recent years important new contributions have resulted from investigation of natural neutrinos from cosmic rays, nearby stars (the sun), or distant sources, such as the 1987 supernova. The supernova observations marked the start of a new era in neutrino astronomy, but neutrino telescopes were anyway assured of an important ongoing role.

A model for pseudo-Dirac neutrinos: leptogenesis and ultra-high energy neutrinos

Energy Technology Data Exchange (ETDEWEB)

Ahn, Y.H. [Center for Theoretical Physics of the Universe, Institute for Basic Science (IBS),Daejeon, 34051 (Korea, Republic of); Kang, Sin Kyu [Insitute for Convergence Fundamental Study, School of Liberal Arts, Seoul-Tech.,Seoul, 01811 (Korea, Republic of); Kim, C.S. [Dept. of Physics and IPAP, Yonsei University,Seoul, 120-749 (Korea, Republic of)

2016-10-18

We propose a model where sterile neutrinos are introduced to make light neutrinos to be pseudo-Dirac particles. It is shown how tiny mass splitting necessary for realizing pseudo-Dirac neutrinos can be achieved. Within the model, we show how leptogenesis can be successfully generated. Motivated by the recent observation of very high energy neutrino events at IceCube, we study a possibility to observe the effects of the pseudo-Dirac property of neutrinos by performing astronomical-scale baseline experiments to uncover the oscillation effects of very tiny mass splitting. We also discuss future prospect to observe the effects of the pseudo-Dirac property of neutrinos at high energy neutrino experiments.

Medida Socioeducativa de Internação: dos Corpos Dóceis às Vidas Nuas

Directory of Open Access Journals (Sweden)

Andrea Cristina Coelho Scisleski

Full Text Available O presente artigo tem como objetivo a problematização dos modos pelos quais a tecnologia disciplinar, presente nas medidas socioeducativas de internação direcionadas aos jovens em conflito com a lei, vem sendo operacionalizada. Tomamos como fio condutor as reflexões de Michel Foucault e Giorgio Agamben para problematizar a vida enquanto objeto político a ser governado para determinado fim e que sofre intervenções não apenas para seu fortalecimento, mas que levam à desproteção jurídica e à morte política, ou mesmo biológica. A investigação se desenvolveu em três momentos metodológicos: oitiva de audiências na Vara da Infância e da Juventude, visita a uma unidade educacional de internação e leitura de processos jurídicos e das normativas legais voltadas para a população em questão. Assim, por meio do que encontramos na pesquisa, entende-se que a tecnologia disciplinar, do modo que vem sendo utilizada nas medidas socioeducativas de internação, assemelha-se mais a um dispositivo de controle com o objetivo meramente de docilizá-los, reduzindo o sujeito à vida nua; isto é, como mero corpo biológico que sofre efeitos de uma ação, do que propriamente um método socioeducativo como estabelecem o Estatuto da Criança e do Adolescente e o Sistema Nacional de Atendimento Socioeducativo.

The ideal neutrino beams

CERN Document Server

Lindroos, Mats

2009-01-01

The advance in neutrino oscillation physics is driven by the availability of well characterized and high flux neutrino beams. The three present options for the next generation neutrino oscillation facility are super beams, neutrino factories and beta-beams. A super-beam is a very high intensity classical neutrino beam generated by protons impinging on a target where the neutrinos are generated by the secondary particles decaying in a tunnel down streams of the target. In a neutrino factory the neutrinos are generated from muons decaying in a storage ring with long straight sections pointing towards the detectors. In a beta-beam the neutrinos are also originating from decay in a storage ring but the decaying particles are radioactive ions rather than muons. I will in this presentation review the three options and discuss the pros and cons of each. The present joint design effort for a future high intensity neutrino oscillation in Europe within a common EU supported design study, EURONU, will also be presented....

50 years of neutrinos

CERN Document Server

Goldhaber, M

1980-01-01

On December 4 1930, Wolfgang Pauli addressed an "open letter" to Lise Meitner and others attending a physics meeting, suggesting the neutrino as a way out of the difficulties confronted in beta rays research, especially by the existence of a continuous beta spectrum. He proposed a new particle later called the neutrino. The prehistory leading up to Pauli's letter will be reviewed, as well as the later discovery of the electron-neutrino followed by the muon-neutrino. There are now believed to be three different types of neutrino and their anti-particles. Neutrinos have a spin 1/2; but only one spin component has been found in nature: neutrinos go forward as "left-handed" screws and anti-neutrinos as "right-handed" ones. A question still not convincingly resolved today is wether neutrinos have a mass different from zero and, if they do, what consequences this would have for the behaviour of neutrinos and for cosmology.

The solar neutrinos epopee

CERN Document Server

Lasserre, T

2003-01-01

The 2002 year has been fruitful for the neutrino physics. First, the Sudbury Neutrino Observatory (SNO) experiment has shown that the electron neutrinos nu sub e emitted by the sun are converted into muon neutrinos (nu submu) and tau neutrinos (nu subtau), thus closing the 30 years old problem of solar neutrinos deficit. This discovery validates the model of nuclear energy production inside the sun but it shakes the theory describing the weak interactions between the fundamental constituents of matter. This theory considers the neutrinos (and the photons) as massless particles, while the taste conversion phenomenon necessarily implies that neutrinos have a mass. In October 2000, the Universe exploration by the cosmic neutrinos is jointly recognized by R. Davis (USA) and M. Koshiba (Japan) who received the Nobel price of physics. Finally, in December 2000, the KamLAND experiment quantitatively demonstrated the neutrinos metamorphosis by detecting a deficit in the flux of electron antineutrinos coming from the ...

Neutrino 2004: Collection of Presentations

International Nuclear Information System (INIS)

2004-01-01

The scientific program covers the latest developments in neutrino physics, astrophysics and related topics through a set of invited talks and 2 poster sessions. The following issues are addressed: - solar neutrinos, - atmospheric neutrinos, - short and long baseline experiments, - neutrino oscillations, - double beta decay, - direct neutrino mass limits, - theory for neutrino masses, neutrino telescopes and ultra-high energy neutrinos, - dark matter searches, - neutrino in astrophysics and cosmology, and - future projects beams and experiments

Neutrino 2004: Collection of Presentations

Energy Technology Data Exchange (ETDEWEB)

NONE

2004-07-01

The scientific program covers the latest developments in neutrino physics, astrophysics and related topics through a set of invited talks and 2 poster sessions. The following issues are addressed: - solar neutrinos, - atmospheric neutrinos, - short and long baseline experiments, - neutrino oscillations, - double beta decay, - direct neutrino mass limits, - theory for neutrino masses, neutrino telescopes and ultra-high energy neutrinos, - dark matter searches, - neutrino in astrophysics and cosmology, and - future projects beams and experiments.

Neutrino oscillations and the seesaw origin of neutrino mass

Energy Technology Data Exchange (ETDEWEB)

Miranda, O.G., E-mail: omr@fis.cinvestav.mx [Departamento de Física, Centro de Investigación y de Estudios Avanzados del IPN, Apdo. Postal 14-740, 07000 Mexico, Distrito Federal (Mexico); Valle, J.W.F. [AHEP Group, Institut de Física Corpuscular – C.S.I.C./Universitat de València, Parc Cientific de Paterna, C/Catedratico José Beltrán, 2, E-46980 Paterna (València) (Spain)

2016-07-15

The historical discovery of neutrino oscillations using solar and atmospheric neutrinos, and subsequent accelerator and reactor studies, has brought neutrino physics to the precision era. We note that CP effects in oscillation phenomena could be difficult to extract in the presence of unitarity violation. As a result upcoming dedicated leptonic CP violation studies should take into account the non-unitarity of the lepton mixing matrix. Restricting non-unitarity will shed light on the seesaw scale, and thereby guide us towards the new physics responsible for neutrino mass generation.

Significados de las medidas de tendencia central : un estudio con alumnos universitarios de carreras de humanidades.

OpenAIRE

Sayritupac Gutierrez, Javier

2013-01-01

En el presente trabajo de investigación se analiza los significados personales e institucionales de las medidas de tendencia central en un estudio con alumnos de primeros ciclos de las carreras de humanidades de la Pontificia Universidad Católica del Perú. Para realizar este análisis se consideró como marco teórico el Enfoque Ontosemiótico de la Cognición e Instrucción Matemática (EOS), el cual nos brindó las herramientas necesarias para el análisis de nuestro objeto de estu...

Comparación de las medidas del ángulo kappa realizadas mediante pupilometría y topografía corneal

OpenAIRE

Marcos Pérez, Mario

2016-01-01

El ojo no es un sistema óptico centrado, por ello surge la necesidad de definir ejes visuales. El ángulo kappa está formado entre el eje pupilar y la línea de mirada, es un parámetro mensurable y relevante a la hora de afrontar cirugía refractiva. El objetivo del trabajo es demostrar la intercambiabilidad de las medidas de kappa con los dispositivos Galilei G4 y Allegro Topolyzer. En la literatura no se encuentra un estudio similar, con lo que resulta conveniente. Para ello se realizan medida...

GRITO DE SOCORRO: TENHO MEDO DE MORRER - A VIOLÊNCIA DOMÉSTICA E O USO DA MEDIDA PROTETIVA

Directory of Open Access Journals (Sweden)

Elizangêla Silva Paiva

2018-03-01

Full Text Available O presente artigo trata-se da Lei 11.340/06, mais conhecida como Lei Maria da Penha. Tem-se o objetivo de demonstrar a importância da lei citada. Para a realização de tal estudo, foram analisadas obras bibliográficas. Apresentando conceitos trazidos por Dias (2007, Mirabetti (2000, Souza (2009, entre outros; busca-se desenvolver o entendimento sobre as formas de violência dos casos onde a referida lei poderá ser aplicada. Seguindo esta linha de raciocínio, apresentam-se as soluções sustentadas pela lei Maria da Penha, analisando-se o contexto do caso concreto para aplicar-se uma medida eficaz. Ao estudarem-se estas medidas, nota-se a existência de vários casos aos quais não se verifica a eficácia da sansão imposta; neste diapasão, tem-se um breve estudo apresentando as principais causas que podem justificar a origem desta questão.

Neutrinos from WIMP annihilations in the Sun including neutrino oscillations

International Nuclear Information System (INIS)

Blennow, Mattias; Edsjö, Joakim; Ohlsson, Tommy

2011-01-01

The prospects to detect neutrinos from the Sun arising from dark matter annihilations in the core of the Sun are reviewed. Emphasis is placed on new work investigating the effects of neutrino oscillations on the expected neutrino fluxes.

Neutrinos from WIMP annihilations in the Sun including neutrino oscillations

International Nuclear Information System (INIS)

Blennow, Mattias; Edsjoe, Joakim; Ohlsson, Tommy

2006-01-01

The prospects for detecting neutrinos from the Sun arising from dark matter annihilations in the core of the Sun are reviewed. Emphasis is placed on new work investigating the effects of neutrino oscillations on the expected neutrino fluxes

Identifying the neutrino mass spectrum from a supernova neutrino burst

International Nuclear Information System (INIS)

Dighe, A.S.; Smirnov, A.Yu.

1999-12-01

We study the role that the future detection of the neutrino burst from a galactic supernova can play in the reconstruction of the neutrino mass spectrum. We consider all possible 3ν mass and flavor spectra which describe the solar and atmospheric neutrino data. For each of these spectra we find the observable effects of the supernova neutrino conversions both in the matter of the star and the earth. We show that studies of the electron neutrino and antineutrino spectra as well as observations of the neutral current effects from supernova will allow us (i) to identify the solar neutrino solution, (ii) to determine the type of mass hierarchy (normal or inverted) and (iii) to probe the mixing vertical bar U e3 vertical bar 2 to values as low as 10 -4 - 10 -3 . (author)

Determination of the atmospheric neutrino fluxes from atmospheric neutrino data

International Nuclear Information System (INIS)

Gonzalez-Garcia, C.; Maltoni, M.; Rojo, J.

2006-06-01

The precise knowledge of the atmospheric neutrino fluxes is a key ingredient in the interpretation of the results from any atmospheric neutrino experiment. In the standard data analysis, these fluxes are theoretical inputs obtained from sophisticated numerical calculations based on the convolution of the primary cosmic ray spectrum with the expected yield of neutrinos per incident cosmic ray. In this work we present an alternative approach to the determination of the atmospheric neutrino fluxes based on the direct extraction from the experimental data on neutrino event rates. The extraction is achieved by means of a combination of artificial neural networks as interpolants and Monte Carlo methods for faithful error estimation. (author)

Determination of the atmospheric neutrino fluxes from atmospheric neutrino data

International Nuclear Information System (INIS)

Gonzalez-Garcia, Concepcion; Maltoni, Michele; Rojo, Joan

2006-01-01

The precise knowledge of the atmospheric neutrino fluxes is a key ingredient in the interpretation of the results from any atmospheric neutrino experiment. In the standard data analysis, these fluxes are theoretical inputs obtained from sophisticated numerical calculations based on the convolution of the primary cosmic ray spectrum with the expected yield of neutrinos per incident cosmic ray. In this work we present an alternative approach to the determination of the atmospheric neutrino fluxes based on the direct extraction from the experimental data on neutrino event rates. The extraction is achieved by means of a combination of artificial neural networks as interpolants and Monte Carlo methods for faithful error estimation

Acidentes perfurocortantes e medidas preventivas para hepatite B adotadas por profissionais de Enfermagem nos serviços de urgência e emergência de Teresina, Piauí

Directory of Open Access Journals (Sweden)

Telma Maria Evangelista de Araújo

Full Text Available Objetivos analisar a ocorrência de acidentes perfurocortantes e as medidas preventivas associadas à hepatite B entre profissionais de Enfermagem em serviços de urgência e emergência. Métodos estudo transversal analítico com aplicação de questionário a 317 participantes de cinco hospitais públicos de Teresina, PI, em 2010. Resultados 152 (47,9% referiram ter sofrido acidente perfurocortante; entre as categorias, 27,3% dos Enfermeiros, 48,2% dos Auxiliares, 52,6% dos Técnicos de Enfermagem. A chance de um profissional de nível médio (Auxiliar ou Técnico sofrer um acidente perfurocortante é de 2,8 (1,38-5,67 vezes maior que o de nível superior (Enfermeiros. A agulha foi o instrumento causador mais frequente (77,0%. A não notificação do acidente foi expressiva entre Técnicos (67,0%, Auxiliares (70,0% e Enfermeiros (75,0%, assim como a não adoção de medidas profiláticas pós-exposição (84,9%, em média. As três categorias profissionais referiram uso de luvas como o EPI mais utilizado. Os Auxiliares de Enfermagem apresentaram o menor percentual (47,0% de esquema vacinal completo para hepatite B. Discussão um percentual expressivo de profissionais de Enfermagem sofreu acidente perfurocortante no trabalho com baixa adoção de medidas preventivas e profiláticas, reforçando a necessidade de fortalecimento de estratégias que visem à saúde do trabalhador no âmbito hospitalar.

Neutrinos and dark energy

International Nuclear Information System (INIS)

Schrempp, L.

2008-02-01

From the observed late-time acceleration of cosmic expansion arises the quest for the nature of Dark Energy. As has been widely discussed, the cosmic neutrino background naturally qualifies for a connection with the Dark Energy sector and as a result could play a key role for the origin of cosmic acceleration. In this thesis we explore various theoretical aspects and phenomenological consequences arising from non-standard neutrino interactions, which dynamically link the cosmic neutrino background and a slowly-evolving scalar field of the dark sector. In the considered scenario, known as Neutrino Dark Energy, the complex interplay between the neutrinos and the scalar field not only allows to explain cosmic acceleration, but intriguingly, as a distinct signature, also gives rise to dynamical, time-dependent neutrino masses. In a first analysis, we thoroughly investigate an astrophysical high energy neutrino process which is sensitive to neutrino masses. We work out, both semi-analytically and numerically, the generic clear-cut signatures arising from a possible time variation of neutrino masses which we compare to the corresponding results for constant neutrino masses. Finally, we demonstrate that even for the lowest possible neutrino mass scale, it is feasible for the radio telescope LOFAR to reveal a variation of neutrino masses and therefore to probe the nature of Dark Energy within the next decade. A second independent analysis deals with the recently challenged stability of Neutrino Dark Energy against the strong growth of hydrodynamic perturbations, driven by the new scalar force felt between neutrinos. Within the framework of linear cosmological perturbation theory, we derive the equation of motion of the neutrino perturbations in a model-independent way. This equation allows to deduce an analytical stability condition which translates into a comfortable upper bound on the scalar-neutrino coupling which is determined by the ratio of the densities in cold dark

Neutrinos and dark energy

Energy Technology Data Exchange (ETDEWEB)

Schrempp, L.

2008-02-15

From the observed late-time acceleration of cosmic expansion arises the quest for the nature of Dark Energy. As has been widely discussed, the cosmic neutrino background naturally qualifies for a connection with the Dark Energy sector and as a result could play a key role for the origin of cosmic acceleration. In this thesis we explore various theoretical aspects and phenomenological consequences arising from non-standard neutrino interactions, which dynamically link the cosmic neutrino background and a slowly-evolving scalar field of the dark sector. In the considered scenario, known as Neutrino Dark Energy, the complex interplay between the neutrinos and the scalar field not only allows to explain cosmic acceleration, but intriguingly, as a distinct signature, also gives rise to dynamical, time-dependent neutrino masses. In a first analysis, we thoroughly investigate an astrophysical high energy neutrino process which is sensitive to neutrino masses. We work out, both semi-analytically and numerically, the generic clear-cut signatures arising from a possible time variation of neutrino masses which we compare to the corresponding results for constant neutrino masses. Finally, we demonstrate that even for the lowest possible neutrino mass scale, it is feasible for the radio telescope LOFAR to reveal a variation of neutrino masses and therefore to probe the nature of Dark Energy within the next decade. A second independent analysis deals with the recently challenged stability of Neutrino Dark Energy against the strong growth of hydrodynamic perturbations, driven by the new scalar force felt between neutrinos. Within the framework of linear cosmological perturbation theory, we derive the equation of motion of the neutrino perturbations in a model-independent way. This equation allows to deduce an analytical stability condition which translates into a comfortable upper bound on the scalar-neutrino coupling which is determined by the ratio of the densities in cold dark

Neutrino-Electron Scattering in MINERvA for Constraining the NuMI Neutrino Flux

Energy Technology Data Exchange (ETDEWEB)

Park, Jaewon [Univ. of Rochester, NY (United States)

2013-01-01

Neutrino-electron elastic scattering is used as a reference process to constrain the neutrino flux at the Main Injector (NuMI) beam observed by the MINERvA experiment. Prediction of the neutrino flux at accelerator experiments from other methods has a large uncertainty, and this uncertainty degrades measurements of neutrino oscillations and neutrino cross-sections. Neutrino-electron elastic scattering is a rare process, but its cross-section is precisely known. With a sample corresponding to $3.5\\times10^{20}$ protons on target in the NuMI low-energy neutrino beam, a sample of $120$ $\

GENERAL ASPECTS OF BODY MEASURES, WEIGHT AND SCORE CONDITION FEMALE NELORE BREED (Bos taurus indicus ON THE PERIOD OF 12 MONTHS ESTUDIO DE MEDIDAS CORPORALES, PESO VIVO Y CONDICIÓN CORPORAL DE BOVINOS HEMBRAS DE LA RAZA NELORE (Bos taurus indicus POR 12 MESES ESTUDO DE MEDIDAS CORPORAIS, PESO VIVO E CONDIÇÃO CORPORAL DE FÊMEAS DA RAÇA NELORE (Bos taurus indicus AO LONGO DE 12 MESES

Directory of Open Access Journals (Sweden)

Arcádio de Los Reys Borjas

2008-04-01

las medidas corporales (p<0,05 entre colectas. Para las vacas el perímetro toráxico presentó diferencia significativa (p<0,05. La relación entre peso vivo condición corporal con el tiempo mostró ecuación cuadrática y fueron parecidas y paralelas para a condición corporal. En el peso vivo, la parte cóncava de la curva para las vacas fue mas abierta comparada a las de vaquillonas. Los coeficientes de correlación entre medidas corporales lineares con las medidas de la anca fueron elevadas (p<0,001, excepto para el perímetro toráxico con largura de la anca. Las correlaciones del peso vivo y condición corporal con medidas corporales fueron significativas (p<0,001, excepto para la condición corporal con la largura de la anca en las categorías; condición corporal versus altura de la anca y peso vivo con largura de la anca para las vacas. Como conclusiones de este trabajo: hubo una variación creciente de las medidas corporales en las vaquillonas en el período de las colecta. El peso vivo, la condición corporal y perímetro toráxico estuvieron relacionados con diferentes períodos del ano que fue realizada el experimento. En vacas las variações a lo largo de año fueron de 14,79%, 31,53% e 6,74%, respectivamente. Las medidas externas ísquio-iliacas, como altura e largura, estuvieron correlacionadas con medidas de tamaño y peso. Vaquillonas en fase de crecimiento tuvieron un comportamiento de forma análoga a las vacas con respecto al peso vivo y condición corporal. Mas investigaciones serian necesarias de las relaciones de las medidas corporales, peso vivo y condición corporal con los aspectos productivos e reproductivos. RESUMO – Objetivou-se verificar alterações e correlações entre medidas corporais em rebanho bovino de novilhas e vacas da raça Nelore. Avaliaram-se 487 fêmeas, quanto ao peso vivo, condição corporal, perímetro torácico, comprimento corporal, altura de cernelha e medidas da garupa. Foram realizadas oito coletas ao longo

Determination of the Atmospheric Neutrino Fluxes from Atmospheric Neutrino Data

NARCIS (Netherlands)

Gonzalez-Garcia, M. C.; Maltoni, M.; Rojo, J.

2006-01-01

The precise knowledge of the atmospheric neutrino fluxes is a key ingredient in the interpretation of the results from any atmospheric neutrino experiment. In the standard atmospheric neutrino data analysis, these fluxes are theoretical inputs obtained from sophisticated numerical calculations based

Neutrinos in Nuclear Physics

Energy Technology Data Exchange (ETDEWEB)

McKeown, Bob [bmck@jlab.org

2015-06-01

Since the discovery of nuclear beta decay, nuclear physicists have studied the weak interaction and the nature of neutrinos. Many recent and current experiments have been focused on the elucidation of neutrino oscillations and neutrino mass. The quest for the absolute value of neutrino mass continues with higher precision studies of the tritium beta decay spectrum near the endpoint. Neutrino oscillations are studied through measurements of reactor neutrinos as a function of baseline and energy. And experiments searching for neutrinoless double beta decay seek to discover violation of lepton number and establish the Majorana nature of neutrino masses.

Future neutrino experiments

CERN Document Server

Di Lella, L

2001-01-01

Future experiments to search for neutrino oscillations using neutrinos from the Sun, from reactors and accelerators are reviewed. Possible long-term developments based on neutrino factories are also described. (29 refs).

Right-handed neutrinos at CERN LHC and the mechanism of neutrino mass generation

International Nuclear Information System (INIS)

Kersten, Joern; Smirnov, Alexei Yu.

2007-01-01

We consider the possibility to detect right-handed neutrinos, which are mostly singlets of the standard model gauge group, at future accelerators. Substantial mixing of these neutrinos with the active neutrinos requires a cancellation of different contributions to the light neutrino mass matrix at the level of 10 -8 . We discuss possible symmetries behind this cancellation and argue that for three right-handed neutrinos they always lead to conservation of total lepton number. Light neutrino masses can be generated by small perturbations violating these symmetries. In the most general case, LHC physics and the mechanism of neutrino mass generation are essentially decoupled; with additional assumptions, correlations can appear between collider observables and features of the neutrino mass matrix

Constraining neutrino magnetic moment with solar and reactor neutrino data

OpenAIRE

Tortola, M. A.

2004-01-01

We use solar neutrino data to derive stringent bounds on Majorana neutrino transition moments (TMs). Such moments, if present, would contribute to the neutrino-electron scattering cross section and hence alter the signal observed in Super-Kamiokande. Using the latest solar neutrino data, combined with the results of the reactor experiment KamLAND, we perform a simultaneous fit of the oscillation parameters and TMs. Furthermore, we include data from the reactor experiments Rovno, TEXONO and MU...

When neutrinos attack - the impact of agressive neutrinos in astrophysics.

Science.gov (United States)

Kneller, James

2004-11-01

Of all the constituents within the standard model of particle physics our understanding of the neutrino has benefited the most from the interaction of astrophysics and `terraphysics'. Much has been learned about the properties of the neutrino from each: experiments here on Earth temper our appreciation of the role that neutrinos play in the cosmos while astrophysics can provide the densities and temperatures in which the neutrinos do more than simply flee. But their reluctance to interact means that it is not until we venture into the most extreme environments of astrophysics that we observe neutrinos pushing back' as hard as they are being pushed'. We review two sites where this occurs: the early Universe and the accretion disk, engines' of gamma ray bursts. Neutrinos play an important role in the evolution of the early Universe with a particular focus upon the electron neutrino in determining the primordial elemental composition via its participation in the most important reaction at that time. Within gamma ray burst accretion disks we again see the electron neutrinos at work in the nuclear reactions and through their function as the coolant' for the disk. Removal of the disk energy, and its deposition into the remnants of the massive star surrounding the disk, may lead to the formation of highly relativistic jets that will later be observed as the burst. We show what has been learned so far about the neutrino and its properties from the study of such environments and discuss where future research is heading.

Effects of neutrino oscillation on supernova neutrino. Inverted mass hierarchy

International Nuclear Information System (INIS)

Takahashi, Keitaro; Sato, Katsuhiko

2003-01-01

We study the effects of neutrino oscillation on supernova neutrinos in the case of the inverted mass hierarchy (m 3 1 2 ) as well as the normal mass hierarchy (m 1 2 3 ). Numerical analysis using realistic supernova and presupernova models allows us to investigate quantitatively the possibility to probe neutrino oscillation parameters. We show that information about the mass hierarchy can be obtained if θ 13 is rather large (sin 2 2θ 13 > 10 -3 ) and that θ 13 can be probed effectively by SuperKamiokande if the neutrino mass hierarchy is inverted. Errors due to the uncertainty in the original neutrino spectra and the Earth effect are also discussed. (author)

Preferencias de estados de salud y medidas de utilidad = Preferences of states of health and measurements of utility

Directory of Open Access Journals (Sweden)

Yepes-Nuñez, Juan José

2011-12-01

Full Text Available La medición de los valores del estado de salud, preferencias y utilidad calcula el valor o la conveniencia de un estado de salud contra un instrumento externo; son medidas genéricas de la calidad de vida relacionada con la salud (CVRS y resumen el valor de esta en un solo número entre 0 (cero y 1 (uno. Las medidas de preferencias de estados de salud y de utilidad difieren de las medidas generales y específicas obtenidas mediante cuestionarios de CVRS en áreas importantes. Primero, calculan las predilecciones de los individuos por alternativas. Segundo, proveen un resultado completo de la CVRS. Tercero, ofrecen una unidad común de análisis. Existen dos métodos para la medición de las utilidades, uno directo y otro indirecto, que se conocen también como utilidades multiatributo o sistemas de clasificación de estados de salud. El proceso directo de medición consiste en un agregado de descripciones que un entrevistador presenta a los encuestados. Para las mediciones indirectas se aplican solamente cuestionarios. El objetivo principal de este artículo es describir los principales métodos de valoración de utilidades, con el fin de dar a conocer los desenlaces que actualmente se utilizan tanto en estudios de CVRS como en evaluaciones económicas.

Radiative neutrino mass model with degenerate right-handed neutrinos

International Nuclear Information System (INIS)

Kashiwase, Shoichi; Suematsu, Daijiro

2016-01-01

The radiative neutrino mass model can relate neutrino masses and dark matter at a TeV scale. If we apply this model to thermal leptogenesis, we need to consider resonant leptogenesis at that scale. It requires both finely degenerate masses for the right-handed neutrinos and a tiny neutrino Yukawa coupling. We propose an extension of the model with a U(1) gauge symmetry, in which these conditions are shown to be simultaneously realized through a TeV scale symmetry breaking. Moreover, this extension can bring about a small quartic scalar coupling between the Higgs doublet scalar and an inert doublet scalar which characterizes the radiative neutrino mass generation. It also is the origin of the Z 2 symmetry which guarantees the stability of dark matter. Several assumptions which are independently supposed in the original model are closely connected through this extension. (orig.)

Homestake result, sterile neutrinos, and low energy solar neutrino experiments

Science.gov (United States)

de Holanda, P. C.; Smirnov, A. Yu.

2004-06-01

The Homestake result is about ˜2σ lower than the Ar-production rate, QAr, predicted by the large mixing angle (LMA) Mikheyev-Smirnov-Wolfenstein solution of the solar neutrino problem. Also there is no apparent upturn of the energy spectrum (R≡Nobs/NSSM) at low energies in SNO and Super-Kamiokande. Both these facts can be explained if a light, Δm201˜(0.2 2)×10-5 eV2, sterile neutrino exists which mixes very weakly with active neutrinos: sin2 2α˜(10-5 10-3). We perform both the analytical and numerical study of the conversion effects in the system of two active neutrinos with the LMA parameters and one weakly mixed sterile neutrino. The presence of sterile neutrino leads to a dip in the survival probability in the intermediate energy range E=(0.5 5) MeV thus suppressing the Be, or/and pep, CNO, as well as B electron neutrino fluxes. Apart from diminishing QAr it leads to decrease of the Ge-production rate and may lead to the decrease of the BOREXINO signal as well as the CC/NC ratio at SNO. Future studies of the solar neutrinos by SNO, SK, BOREXINO, and KamLAND as well as by the new low energy experiments will allow us to check this possibility.

Introduction to massive neutrinos

International Nuclear Information System (INIS)

Kayser, B.

1984-01-01

We discuss the theoretical ideas which make it natural to expect that neutrinos do indeed have mass. Then we focus on the physical consequences of neutrino mass, including neutrino oscillation and other phenomena whose observation would be very interesting, and would serve to demonstrate that neutrinos are indeed massive. We comment on the legitimacy of comparing results from different types of experiments. Finally, we consider the question of whether neutrinos are their own antiparticles. We explain what this question means, discuss the nature of a neutrino which is its own antiparticles, and consider how one might determine experimentally whether neutrinos are their own antiparticles or not

Solar neutrino detection

International Nuclear Information System (INIS)

Miramonti, Lino

2009-01-01

More than 40 years ago, neutrinos where conceived as a way to test the validity of the solar models which tell us that stars are powered by nuclear fusion reactions. The first measurement of the neutrino flux, in 1968 in the Homestake mine in South Dakota, detected only one third of the expected value, originating what has been known as the Solar Neutrino Problem. Different experiments were built in order to understand the origin of this discrepancy. Now we know that neutrinos undergo oscillation phenomenon changing their nature traveling from the core of the Sun to our detectors. In the work the 40 year long saga of the neutrino detection is presented; from the first proposals to test the solar models to last real time measurements of the low energy part of the neutrino spectrum.

Molybdenum solar neutrino experiment

International Nuclear Information System (INIS)

Wolfsberg, K.; Cowan, G.A.; Bryant, E.A.

1984-01-01

The goal of the molybdenum solar neutrino experiment is to deduce the 8 B solar neutrino flux, averaged over the past several million years, from the concentration of 98 Tc in a deeply buried molybdenum deposit. The experiment is important to an understanding of stellar processes because it will shed light on the reason for the discrepancy between theory and observation of the chlorine solar neutrino experiment. Possible reasons for the discrepancy may lie in the properties of neutrinos (neutrino oscillations or massive neutrinos) or in deficiencies of the standard solar model. The chlorine experiment only measures the 8 B neutrino flux in current times and does not address possible temporal variations in the interior of the sun, which are also not considered in the standard model. In the molybdenum experiment, we plan to measure 98 Tc (4.2 Myr), also produced by 8 B neutrinos, and possibly 97 Tc (2.6 Myr), produced by lower energy neutrinos

The physics of neutrinos

CERN Document Server

Barger, Vernon D; Whisnant, Kerry

2012-01-01

The physics of neutrinos- uncharged elementary particles that are key to helping us better understand the nature of our universe - is one of the most exciting frontiers of modern science. This book provides a comprehensive overview of neutrino physics today and explores promising new avenues of inquiry that could lead to future breakthroughs. The Physics of Neutrinos begins with a concise history of the field and a tutorial on the fundamental properties of neutrinos, and goes on to discuss how the three neutrino types interchange identities as they propagate from their sources to detectors. The book shows how studies of neutrinos produced by such phenomena as cosmic rays in the atmosphere and nuclear reactions in the solar interior provide striking evidence that neutrinos have mass, and it traces our astounding progress in deciphering the baffling experimental findings involving neutrinos. The discovery of neutrino mass offers the first indication of a new kind of physics that goes beyond the Standard Model ...

Decays of supernova neutrinos

International Nuclear Information System (INIS)

Lindner, Manfred; Ohlsson, Tommy; Winter, Walter

2002-01-01

Supernova neutrinos could be well-suited for probing neutrino decay, since decay may be observed even for very small decay rates or coupling constants. We will introduce an effective operator framework for the combined description of neutrino decay and neutrino oscillations for supernova neutrinos, which can especially take into account two properties: one is the radially symmetric neutrino flux, allowing a decay product to be re-directed towards the observer even if the parent neutrino had a different original direction of propagation. The other is decoherence because of the long baselines for coherently produced neutrinos. We will demonstrate how to use this effective theory to calculate the time-dependent fluxes at the detector. In addition, we will show the implications of a Majoron-like decay model. As a result, we will demonstrate that for certain parameter values one may observe some effects which could also mimic signals similar to the ones expected from supernova models, making it in general harder to separate neutrino and supernova properties

Case for neutrino oscillations

International Nuclear Information System (INIS)

Ramond, P.

1982-01-01

The building of a machine capable of producing an intense, well-calibrated beam of muon neutrinos is regarded by particle physicists with keen interest because of its ability of studying neutrino oscillations. The possibility of neutrino oscillations has long been recognized, but it was not made necessary on theoretical or experimental grounds; one knew that oscillations could be avoided if neutrinos were massless, and this was easily done by the conservation of lepton number. The idea of grand unification has led physicists to question the existence (at higher energies) of global conservation laws. The prime examples are baryon-number conservation, which prevents proton decay, and lepton-number conservation, which keeps neutrinos massless, and therefore free of oscillations. The detection of proton decay and neutrino oscillations would therefore be an indirect indication of the idea of Grand Unification, and therefore of paramount importance. Neutrino oscillations occur when neutrinos acquire mass in such a way that the neutrino mass eigenstates do not match the (neutrino) eigenstates produced by the weak interactions. We shall study the ways in which neutrinos can get mass, first at the level of the standard SU 2 x U 1 model, then at the level of its Grand Unification Generalizations

A search for oscillations of muon-neutrinos to electron-neutrinos

CERN Document Server

Procario, Michael

1986-01-01

The author has searched in the heavy liquid bubble chamber BEBC for electron neutrino charge current events which could arise from oscillation of the muon neutrinos (average energy ∼1.5 GeV) obtained with a low energy proton beam at the CERN PS targeted 825 m upstream from BEBC. The appearance of electron neutrino CC interactions provides a sensitive indication of nu/sub μ/ → nu/sub e/ oscillation. The author observed 460 muon neutrino CC events and 4 electron neutrino CC events with an estimated background of 3.5 electron neutrino CC events. Using the likelihood ratio method to test the oscillation hypothesis, the author finds no evidence for nu/sub μ/ → nu/sub e/ oscillation and set the limits δm2 ≤ 0.13 eV2 (maximal mixing) and sin22theta ≤ 0.018 for δm2 = 3 eV2 at 90% confidence level

MEDIDA DA ATIVIDADE FÍSICA EM JOVENS BRASILEIROS: REPRODUTIBILIDADE E VALIDADE DO PAQ-C E DO PAQ-A

OpenAIRE

Guedes,Dartagnan Pinto; Guedes,Joana Elisabete Ribeiro Pinto

2015-01-01

Introdução: O Physical Activity Questionnaire for Children (PAQ-C) e o Physical Activity Questionnaire for Adolescents (PAQ-A) foram originalmente propostos para oferecer medidas autorrelatadas da prática de atividade física de jovens. Objetivos: Traduzir para o idioma português, realizar adaptação transcultural e analisar reprodutibilidade e validade concorrente do PAQ-C e do PAQ-A em amostra de jovens brasileiros. Métodos: Versões originais foram traduzidas de acordo com recomendações ...

MINOS Sterile Neutrino Search

Energy Technology Data Exchange (ETDEWEB)

Koskinen, David Jason [Univ. College London, Bloomsbury (United Kingdom)

2009-02-01

The Main Injector Neutrino Oscillation Search (MINOS) is a long-baseline accelerator neutrino experiment designed to measure properties of neutrino oscillation. Using a high intensity muon neutrino beam, produced by the Neutrinos at Main Injector (NuMI) complex at Fermilab, MINOS makes two measurements of neutrino interactions. The first measurement is made using the Near Detector situated at Fermilab and the second is made using the Far Detector located in the Soudan Underground laboratory in northern Minnesota. The primary goal of MINOS is to verify, and measure the properties of, neutrino oscillation between the two detectors using the v _μ→ V_τ transition. A complementary measurement can be made to search for the existence of sterile neutrinos; an oft theorized, but experimentally unvalidated particle. The following thesis will show the results of a sterile neutrino search using MINOS RunI and RunII data totaling ~2.5 x 10²⁰ protons on target. Due to the theoretical nature of sterile neutrinos, complete formalism that covers transition probabilities for the three known active states with the addition of a sterile state is also presented.

Neutrino mass spectrum with υμ → υs oscillations of atmospheric neutrinos

International Nuclear Information System (INIS)

Liu, Q.Y.; Smirnov, A.Yu.

1998-02-01

We consider the ''standard'' spectrum of the active neutrinos (characterized by strong mass hierarchy and small mixing) with additional sterile, υ s . The sterile neutrino mixes strongly with the muon neutrino, so that υ μ ↔ υ s oscillations solve the atmospheric neutrino problem. We show that the parametric enhancement of the υ μ ↔ υ s oscillations occurs for the high energy atmospheric neutrinos which cross the core of the Earth. This can be relevant for the anomaly observed by the MACRO experiment. Solar neutrinos are converted both to υ μ and υ s . The heaviest neutrino (approx. υ τ ) may compose the hot dark matter of the Universe. Phenomenology of this scenario is elaborated and crucial experimental signatures are identified. We also discuss properties of the underlying neutrino mass matrix. (author)

Sudbury neutrino observatory

International Nuclear Information System (INIS)

Ewan, G.T.; Mak, H.B.; Robertson, B.C.

1985-07-01

This report discusses the proposal to construct a unique neutrino observatory. The observatory would contain a Cerenkov detector which would be located 2070 m below the earth's surface in an INCO mine at Creighton near Sudbury and would contain 1000 tons of D20 which is an excellent target material. Neutrinos carry detailed information in their spectra on the reactions taking place deep in the interstellar interior and also provide information on supernova explosions. In addition to their role as astrophysical probes a knowledge of the properties of neutrinos is crucial to theories of grand unification. There are three main objectives of the laboratory. The prime objective will be to study B electron neutrinos from the sun by a direct counting method that will measure their energy and direction. The second major objective will be to establish if electron neutrinos change into other neutrino species in transit from the sun to the earth. Finally it is hoped to be able to observe a supernova with the proposed detector. The features of the Sudbury Neutrino Observatory which make it unique are its high sensitivity to electron neutrinos and its ability to detect all other types of neutrinos of energy greater than 2.2 MeV. In section II of this proposal the major physics objectives are discussed in greater detail. A conceptual design for the detector, and measurements and calculations which establish the feasibility of the neutrino experiments are presented in section III. Section IV is comprised of a discussion on the possible location of the laboratory and Section V contains a brief indication of the main areas to be studied in Phase II of the design study

Neutrino physics with JUNO

Science.gov (United States)

An, Fengpeng; An, Guangpeng; An, Qi; Antonelli, Vito; Baussan, Eric; Beacom, John; Bezrukov, Leonid; Blyth, Simon; Brugnera, Riccardo; Buizza Avanzini, Margherita; Busto, Jose; Cabrera, Anatael; Cai, Hao; Cai, Xiao; Cammi, Antonio; Cao, Guofu; Cao, Jun; Chang, Yun; Chen, Shaomin; Chen, Shenjian; Chen, Yixue; Chiesa, Davide; Clemenza, Massimiliano; Clerbaux, Barbara; Conrad, Janet; D'Angelo, Davide; De Kerret, Hervé; Deng, Zhi; Deng, Ziyan; Ding, Yayun; Djurcic, Zelimir; Dornic, Damien; Dracos, Marcos; Drapier, Olivier; Dusini, Stefano; Dye, Stephen; Enqvist, Timo; Fan, Donghua; Fang, Jian; Favart, Laurent; Ford, Richard; Göger-Neff, Marianne; Gan, Haonan; Garfagnini, Alberto; Giammarchi, Marco; Gonchar, Maxim; Gong, Guanghua; Gong, Hui; Gonin, Michel; Grassi, Marco; Grewing, Christian; Guan, Mengyun; Guarino, Vic; Guo, Gang; Guo, Wanlei; Guo, Xin-Heng; Hagner, Caren; Han, Ran; He, Miao; Heng, Yuekun; Hsiung, Yee; Hu, Jun; Hu, Shouyang; Hu, Tao; Huang, Hanxiong; Huang, Xingtao; Huo, Lei; Ioannisian, Ara; Jeitler, Manfred; Ji, Xiangdong; Jiang, Xiaoshan; Jollet, Cécile; Kang, Li; Karagounis, Michael; Kazarian, Narine; Krumshteyn, Zinovy; Kruth, Andre; Kuusiniemi, Pasi; Lachenmaier, Tobias; Leitner, Rupert; Li, Chao; Li, Jiaxing; Li, Weidong; Li, Weiguo; Li, Xiaomei; Li, Xiaonan; Li, Yi; Li, Yufeng; Li, Zhi-Bing; Liang, Hao; Lin, Guey-Lin; Lin, Tao; Lin, Yen-Hsun; Ling, Jiajie; Lippi, Ivano; Liu, Dawei; Liu, Hongbang; Liu, Hu; Liu, Jianglai; Liu, Jianli; Liu, Jinchang; Liu, Qian; Liu, Shubin; Liu, Shulin; Lombardi, Paolo; Long, Yongbing; Lu, Haoqi; Lu, Jiashu; Lu, Jingbin; Lu, Junguang; Lubsandorzhiev, Bayarto; Ludhova, Livia; Luo, Shu; Lyashuk, Vladimir; Möllenberg, Randolph; Ma, Xubo; Mantovani, Fabio; Mao, Yajun; Mari, Stefano M.; McDonough, William F.; Meng, Guang; Meregaglia, Anselmo; Meroni, Emanuela; Mezzetto, Mauro; Miramonti, Lino; Mueller, Thomas; Naumov, Dmitry; Oberauer, Lothar; Ochoa-Ricoux, Juan Pedro; Olshevskiy, Alexander; Ortica, Fausto; Paoloni, Alessandro; Peng, Haiping; Peng, Jen-Chieh; Previtali, Ezio; Qi, Ming; Qian, Sen; Qian, Xin; Qian, Yongzhong; Qin, Zhonghua; Raffelt, Georg; Ranucci, Gioacchino; Ricci, Barbara; Robens, Markus; Romani, Aldo; Ruan, Xiangdong; Ruan, Xichao; Salamanna, Giuseppe; Shaevitz, Mike; Sinev, Valery; Sirignano, Chiara; Sisti, Monica; Smirnov, Oleg; Soiron, Michael; Stahl, Achim; Stanco, Luca; Steinmann, Jochen; Sun, Xilei; Sun, Yongjie; Taichenachev, Dmitriy; Tang, Jian; Tkachev, Igor; Trzaska, Wladyslaw; van Waasen, Stefan; Volpe, Cristina; Vorobel, Vit; Votano, Lucia; Wang, Chung-Hsiang; Wang, Guoli; Wang, Hao; Wang, Meng; Wang, Ruiguang; Wang, Siguang; Wang, Wei; Wang, Yi; Wang, Yi; Wang, Yifang; Wang, Zhe; Wang, Zheng; Wang, Zhigang; Wang, Zhimin; Wei, Wei; Wen, Liangjian; Wiebusch, Christopher; Wonsak, Björn; Wu, Qun; Wulz, Claudia-Elisabeth; Wurm, Michael; Xi, Yufei; Xia, Dongmei; Xie, Yuguang; Xing, Zhi-zhong; Xu, Jilei; Yan, Baojun; Yang, Changgen; Yang, Chaowen; Yang, Guang; Yang, Lei; Yang, Yifan; Yao, Yu; Yegin, Ugur; Yermia, Frédéric; You, Zhengyun; Yu, Boxiang; Yu, Chunxu; Yu, Zeyuan; Zavatarelli, Sandra; Zhan, Liang; Zhang, Chao; Zhang, Hong-Hao; Zhang, Jiawen; Zhang, Jingbo; Zhang, Qingmin; Zhang, Yu-Mei; Zhang, Zhenyu; Zhao, Zhenghua; Zheng, Yangheng; Zhong, Weili; Zhou, Guorong; Zhou, Jing; Zhou, Li; Zhou, Rong; Zhou, Shun; Zhou, Wenxiong; Zhou, Xiang; Zhou, Yeling; Zhou, Yufeng; Zou, Jiaheng

2016-03-01

The Jiangmen Underground Neutrino Observatory (JUNO), a 20 kton multi-purpose underground liquid scintillator detector, was proposed with the determination of the neutrino mass hierarchy (MH) as a primary physics goal. The excellent energy resolution and the large fiducial volume anticipated for the JUNO detector offer exciting opportunities for addressing many important topics in neutrino and astro-particle physics. In this document, we present the physics motivations and the anticipated performance of the JUNO detector for various proposed measurements. Following an introduction summarizing the current status and open issues in neutrino physics, we discuss how the detection of antineutrinos generated by a cluster of nuclear power plants allows the determination of the neutrino MH at a 3-4σ significance with six years of running of JUNO. The measurement of antineutrino spectrum with excellent energy resolution will also lead to the precise determination of the neutrino oscillation parameters {{sin}}2{θ }12, {{Δ }}{m}212, and | {{Δ }}{m}{ee}2| to an accuracy of better than 1%, which will play a crucial role in the future unitarity test of the MNSP matrix. The JUNO detector is capable of observing not only antineutrinos from the power plants, but also neutrinos/antineutrinos from terrestrial and extra-terrestrial sources, including supernova burst neutrinos, diffuse supernova neutrino background, geoneutrinos, atmospheric neutrinos, and solar neutrinos. As a result of JUNO's large size, excellent energy resolution, and vertex reconstruction capability, interesting new data on these topics can be collected. For example, a neutrino burst from a typical core-collapse supernova at a distance of 10 kpc would lead to ˜5000 inverse-beta-decay events and ˜2000 all-flavor neutrino-proton ES events in JUNO, which are of crucial importance for understanding the mechanism of supernova explosion and for exploring novel phenomena such as collective neutrino oscillations

Evidence for neutrino oscillations in the Sudbury Neutrino Observatory

International Nuclear Information System (INIS)

Marino, Alysia Diane

2004-01-01

The Sudbury Neutrino Observatory (SNO) is a large-volume heavy water Cerenkov detector designed to resolve the solar neutrino problem. SNO observes charged-current interactions with electron neutrinos, neutral-current interactions with all active neutrinos, and elastic-scattering interactions primarily with electron neutrinos with some sensitivity to other flavors. This dissertation presents an analysis of the solar neutrino flux observed in SNO in the second phase of operation, while ∼2 tonnes of salt (NaCl) were dissolved in the heavy water. The dataset here represents 391 live days of data. Only the events above a visible energy threshold of 5.5 MeV and inside a fiducial volume within 550 cm of the center of the detector are studied. The neutrino flux observed via the charged-current interaction is [1.71 ± 0.065(stat.)± 0.068 0.065 (sys.)±0.02(theor.)] x 10 6 cm -2 s -1 , via the elastic-scattering interaction is [2.21±0.22(stat.)± 0.12 0.11 (sys.)±0.01(theor.)] x 10 6 cm -2 s -1 , and via the neutral-current interaction is [5.05±0.23(stat.)± 0.37 0.31 (sys.)±0.06(theor.)] x 10 6 cm -2 s -1 . The electron-only flux seen via the charged-current interaction is more than 7σ below the total active flux seen via the neutral-current interaction, providing strong evidence that neutrinos are undergoing flavor transformation as they travel from the core of the Sun to the Earth. The most likely origin of the flavor transformation is matter-induced flavor oscillation

Frontiers in neutrino physics - Transparencies

International Nuclear Information System (INIS)

Akhmedov, E.; Balantekin, B.; Conrad, J.; Engel, J.; Fogli, G.; Giunti, C.; Espinoza, C.; Lasserre, T.; Lazauskas, R.; Lhuiller, D.; Lindner, M.; Martinez-Pinedo, G.; Martini, M.; McLaughlin, G.; Mirizzi, A.; Pehlivan, Y.; Petcov, S.; Qian, Y.; Serenelli, A.; Stancu, I.; Surman, R.; Vaananen, D.; Vissani, F.; Vogel, P.

2012-01-01

This document gathers the slides of the presentations. The purpose of the conference was to discuss the last advances in neutrino physics. The presentations dealt with: -) the measurement of the neutrino velocity, -) neutrino oscillations, -) anomaly in solar models and neutrinos, -) double beta decay, -) self refraction of neutrinos, -) cosmic neutrinos, -) antineutrino spectra from reactors, and -) some aspects of neutrino physics with radioactive ion beams. (A.C.)

Neutrino Oscillations Physics

Science.gov (United States)

Fogli, Gianluigi

2005-06-01

We review the status of the neutrino oscillations physics, with a particular emphasis on the present knowledge of the neutrino mass-mixing parameters. We consider first the νμ → ντ flavor transitions of atmospheric neutrinos. It is found that standard oscillations provide the best description of the SK+K2K data, and that the associated mass-mixing parameters are determined at ±1σ (and NDF = 1) as: Δm2 = (2.6 ± 0.4) × 10-3 eV2 and sin 2 2θ = 1.00{ - 0.05}{ + 0.00} . Such indications, presently dominated by SK, could be strengthened by further K2K data. Then we point out that the recent data from the Sudbury Neutrino Observatory, together with other relevant measurements from solar and reactor neutrino experiments, in particular the KamLAND data, convincingly show that the flavor transitions of solar neutrinos are affected by Mikheyev-Smirnov-Wolfenstein (MSW) effects. Finally, we perform an updated analysis of two-family active oscillations of solar and reactor neutrinos in the standard MSW case.

Symplectic symmetry of the neutrino mass for many neutrino flavors

International Nuclear Information System (INIS)

Oeztuerk, N.; Ankara Univ.

2001-01-01

The algebraic structure of the neutrino mass Hamiltonian is presented for two neutrino flavors considering both Dirac and Majorana mass terms. It is shown that the algebra is Sp(8) and also discussed how the algebraic structure generalizes for the case of more than two neutrino flavors. (orig.)

Three Dirac neutrinos

International Nuclear Information System (INIS)

Joshipura, A.S.; Rindani, S.D.

1991-01-01

The consequences of imposing an exact L e +L τ -L μ symmetry on a 6x6 matrix describing neutrino masses are discussed. The presence of right-handed neutrinos avoids the need of introducing any SU(2) Higgs triplet. Hence the conflict with the CERN LEP data on the Z width found in earlier models with L e +L τ -L μ symmetry is avoided. The L e +L τ -L μ symmetry provides an interesting realization of a recent proposal of Glashow to accommodate the 17-keV Dirac neutrino in the SU(2)xU(1) theory. All the neutrinos in this model are Dirac particles. The solar-neutrino problem can be solved in an extension of the model which generates a large (∼10 -11 μ B ) magnetic moment for the electron neutrino

Measurement of neutrino flux from neutrino-electron elastic scattering

Science.gov (United States)

Park, J.; Aliaga, L.; Altinok, O.; Bellantoni, L.; Bercellie, A.; Betancourt, M.; Bodek, A.; Bravar, A.; Budd, H.; Cai, T.; Carneiro, M. F.; Christy, M. E.; Chvojka, J.; da Motta, H.; Dytman, S. A.; Díaz, G. A.; Eberly, B.; Felix, J.; Fields, L.; Fine, R.; Gago, A. M.; Galindo, R.; Ghosh, A.; Golan, T.; Gran, R.; Harris, D. A.; Higuera, A.; Kleykamp, J.; Kordosky, M.; Le, T.; Maher, E.; Manly, S.; Mann, W. A.; Marshall, C. M.; Martinez Caicedo, D. A.; McFarland, K. S.; McGivern, C. L.; McGowan, A. M.; Messerly, B.; Miller, J.; Mislivec, A.; Morfín, J. G.; Mousseau, J.; Naples, D.; Nelson, J. K.; Norrick, A.; Nuruzzaman; Osta, J.; Paolone, V.; Patrick, C. E.; Perdue, G. N.; Rakotondravohitra, L.; Ramirez, M. A.; Ray, H.; Ren, L.; Rimal, D.; Rodrigues, P. A.; Ruterbories, D.; Schellman, H.; Solano Salinas, C. J.; Tagg, N.; Tice, B. G.; Valencia, E.; Walton, T.; Wolcott, J.; Wospakrik, M.; Zavala, G.; Zhang, D.; Miner ν A Collaboration

2016-06-01

Muon-neutrino elastic scattering on electrons is an observable neutrino process whose cross section is precisely known. Consequently a measurement of this process in an accelerator-based νμ beam can improve the knowledge of the absolute neutrino flux impinging upon the detector; typically this knowledge is limited to ˜10 % due to uncertainties in hadron production and focusing. We have isolated a sample of 135 ±17 neutrino-electron elastic scattering candidates in the segmented scintillator detector of MINERvA, after subtracting backgrounds and correcting for efficiency. We show how this sample can be used to reduce the total uncertainty on the NuMI νμ flux from 9% to 6%. Our measurement provides a flux constraint that is useful to other experiments using the NuMI beam, and this technique is applicable to future neutrino beams operating at multi-GeV energies.

Geo-neutrino Observation

International Nuclear Information System (INIS)

Dye, S. T.; Alderman, M.; Batygov, M.; Learned, J. G.; Matsuno, S.; Mahoney, J. M.; Pakvasa, S.; Rosen, M.; Smith, S.; Varner, G.; McDonough, W. F.

2009-01-01

Observations of geo-neutrinos measure radiogenic heat production within the earth, providing information on the thermal history and dynamic processes of the mantle. Two detectors currently observe geo-neutrinos from underground locations. Other detection projects in various stages of development include a deep ocean observatory. This paper presents the current status of geo-neutrino observation and describes the scientific capabilities of the deep ocean observatory, with emphasis on geology and neutrino physics.

Sistema de aquisição de dados para equipamento de medida da permeabilidade intrínseca do solo ao ar

Directory of Open Access Journals (Sweden)

Luciano Roberto da Silveira

2011-04-01

Full Text Available A permeabilidade intrínseca - ou simplesmente permeabilidade do solo ao ar - é uma propriedade importante para a identificação de alterações no espaço poroso do solo causadas pelas práticas de manejo, na estimativa de propriedades do solo mais difíceis e onerosas e na composição de modelos de fluxo de fluidos em solos agrícolas e em solos contaminados. O objetivo do presente estudo foi construir um sistema de aquisição de dados (módulo eletrônico e programa computacional para a medida da permeabilidade do solo ao ar em laboratório, utilizando-se materiais disponíveis no local e ferramentas computacionais de acesso livre. O sistema de aquisição de dados mostrou-se bastante preciso na determinação da permeabilidade do solo ao ar, com intervalo de confiança de 9,42 ± 0,085 μm² (95 %, para uma amostra-padrão constituída de partículas com diâmetro de 0,106 a 0,250 mm da fração areia de um Latossolo Vermelho-Amarelo textura média. A estimativa da permeabilidade do solo ao ar, considerando a viscosidade dinâmica do ar em função da temperatura, foi significativamente maior que a estimativa com valor fixo de viscosidade dinâmica em aproximadamente 20 ºC. A medição realizada em uma amostra de solo com estrutura indeformada de um Latossolo Vermelho foi tão precisa quanto à da amostra-padrão, e a estimativa da massa de água removida da amostra foi de 3,27 mg.

Neutrino masses

Energy Technology Data Exchange (ETDEWEB)

Anon.

1986-04-15

Postulated in the early days of quantum mechanics by Wolfgang Pauli to make energy-momentum conservation in nuclear beta decay come out right, the neutrino has never strayed far from physicists' attention. The Moriond Workshop on Massive Neutrinos in Particle Physics and Astrophysics held recently in the French Alps showed that more than half a century after Pauli's prediction, the neutrino stubbornly refuses to yield up all its secrets.

Neutrino mass, a status report

International Nuclear Information System (INIS)

Robertson, R.G.H.

1993-01-01

Experimental approaches to neutrino mass include kinematic mass measurements, neutrino oscillation searches at rectors and accelerators, solar neutrinos, atmospheric neutrinos, and single and double beta decay. The solar neutrino results yield fairly strong and consistent indications that neutrino oscillations are occurring. Other evidence for new physics is less consistent and convincing

Effects of neutrino degeneracy and of downscatter on neutrino radiation from dense stellar cores

International Nuclear Information System (INIS)

Lichtenstadt, I.; Ron, A.; Sack, N.; Wagschal, J.J.; Bludman, S.A.

1978-01-01

A simplified model is presneted for several stages in the development of a neutronization shell in the inner core of a collapsing star. Neutrino degeneracy severely reduces neutrino emission and downscatter in energy, so that for all but the thinest shell sources, surface emission of an approximately Fermi-Dirac neutrino spectrum obtains. The Neutrino spectrum departs from exact Fermi-Dirac neutrino form only because of the outstreaming of low-energy neutrinos.Downscatter by electrons is helped by neutron scatterers present, but except for reducing the peak neutrino energy by about 30%, electrons play no dramatic part. The neutrino degeneracy inhibits downscatter so that the low-energy window in the Fermi-Dirac distribution leads to little neutrino loss.A simple equilibrium radiation picture emerges in which neutrinos are LTE thermally emitted in the neutronization shell and isotropically coherently scattered by neutrons and by nuclei on the way out of the overlying mantle. The Fermi statistics limit on neutrino flux is probably reached in practice, but is, in most cases, still insufficient for mantle blow-off

Accelerator studies of neutrino oscillations

CERN Document Server

Ereditato, A

2000-01-01

The question of whether the neutrino has a non-vanishing mass plays acrucial role in particle physics. A massive neutrino would unambiguously reveal the existence of new physics beyond the Standard Model. In addition, it could have profound implications on astrophysics and cosmology, with effects on the evolution of the Universe. Experiments aiming at direct neutrino-mass measurements based on kinematics have not been able, so far, to measure the very small neutrino mass. Indirect measurements can be performed by exploiting reactions which may only occur for massive neutrinos. Neutrino oscillation is one of those processes. The mass difference between neutrino mass-eigenstates can be inferred from a phase measurement. This feature allows for high sensitivity experiments. Neutrinos from different sources can be used to search for oscillations: solar neutrinos, neutrinos produced in the interaction of cosmic rays with the atmosphere and artificially produced neutrinos from nuclear reactors and particle accelera...

Neutrino physics in heaven

International Nuclear Information System (INIS)

Raffelt, G.

2005-01-01

After a brief overview of the usual topics that connect astrophysics and cosmology with neutrino physics I will focus on two main themes. First, what can we learn from the neutrino signal of a future galactic supernova, in particular about the neutrino mass ordering. Second, what can we learn about neutrino properties from cosmological observables, notably about the neutrino absolute mass scale from cosmological large-scale structure observables. (author)

A measurement of neutrino oscillations with muon neutrinos in the MINOS experiment

Energy Technology Data Exchange (ETDEWEB)

Coleman, Stephen James [College of William and Mary, Williamsburg, VA (United States)

2011-05-01

Experimental evidence has established that neutrino flavor states evolve over time. A neutrino of a particular flavor that travels some distance can be detected in a different neutrino flavor state. The Main Injector Neutrino Oscillation Search (MINOS) is a long-baseline experiment that is designed to study this phenomenon, called neutrino oscillations. MINOS is based at Fermilab near Chicago, IL, and consists of two detectors: the Near Detector located at Fermilab, and the Far Detector, which is located in an old iron mine in Soudan, MN. Both detectors are exposed to a beam of muon neutrinos from the NuMI beamline, and MINOS measures the fraction of muon neutrinos that disappear after traveling the 734 km between the two detectors. One can measure the atmospheric neutrino mass splitting and mixing angle by observing the energy-dependence of this muon neutrino disappearance. MINOS has made several prior measurements of these parameters. Here I describe recently-developed techniques used to enhance our sensitivity to the oscillation parameters, and I present the results obtained when they are applied to a dataset that is twice as large as has been previously analyzed. We measure the mass splitting Δm₂₃² = (2.32_-0.08^+0.12) x 10^-3 eV²/c⁴ and the mixing angle sin²(2θ₃₂) > 0.90 at 90% C.L. These results comprise the world's best measurement of the atmospheric neutrino mass splitting. Alternative disappearance models are also tested. The neutrino decay hypothesis is disfavored at 7.2σ and the neutrino quantum decoherence hypothesis is disfavored at 9.0σ.

Flavor composition of the IceCube neutrinos: A quest for sterile neutrinos?

International Nuclear Information System (INIS)

Biondi, R.

2016-01-01

The identification of flavor content in the cosmic high-energy neutrinos recently observed by the IceCube collaboration could spread the light on the origin of these neutrinos. We study the expected fraction of muon tracks for different cases of the neutrino flavor composition at the sources taking into account uncertainties in the neutrino mixing angles and CP-phase. We show that in the frame of the three known neutrinos it is hard to explain the ν_μ fraction observed at IceCube. However if the cosmic component is produced in some hidden sector, in the form of sterile neutrinos which then oscillate into ordinary ones, a better agreement can be obtained. Especially, in a scenario when heavy dark matter with mass of few PeV decay into sterile neutrinos which then oscillate in ordinary neutrinos due to tiny mixing with the latter, it is possible to explain the low fraction of muon tracks in the events observed by IceCube in the energy region from 60TeV to 2PeV

Measurement of Atmospheric Neutrino Oscillations with Very Large Volume Neutrino Telescopes

Directory of Open Access Journals (Sweden)

J. P. Yáñez

2015-01-01

Full Text Available Neutrino oscillations have been probed during the last few decades using multiple neutrino sources and experimental set-ups. In the recent years, very large volume neutrino telescopes have started contributing to the field. First ANTARES and then IceCube have relied on large and sparsely instrumented volumes to observe atmospheric neutrinos for combinations of baselines and energies inaccessible to other experiments. Using this advantage, the latest result from IceCube starts approaching the precision of other established technologies and is paving the way for future detectors, such as ORCA and PINGU. These new projects seek to provide better measurements of neutrino oscillation parameters and eventually determine the neutrino mass ordering. The results from running experiments and the potential from proposed projects are discussed in this review, emphasizing the experimental challenges involved in the measurements.

Galactic neutrino communication

Energy Technology Data Exchange (ETDEWEB)

Learned, John G. [Department of Physics and Astronomy, University of Hawaii, 2505 Correa Road, Honolulu, HI 96822 (United States)], E-mail: jgl@phys.hawaii.edu; Pakvasa, Sandip [Department of Physics and Astronomy, University of Hawaii, 2505 Correa Road, Honolulu, HI 96822 (United States)], E-mail: pakvasa@phys.hawaii.edu; Zee, A. [Kavli Institute for Theoretical Physics, University of California, Santa Barbara, CA 93106 (United States)], E-mail: zee@kitp.ucsb.edu

2009-01-12

We examine the possibility to employ neutrinos to communicate within the galaxy. We discuss various issues associated with transmission and reception, and suggest that the resonant neutrino energy near 6.3 PeV may be most appropriate. In one scheme we propose to make Z deg. particles in an overtaking e{sup +}-e{sup -} collider such that the resulting decay neutrinos are near the W{sup -} resonance on electrons in the laboratory. Information is encoded via time structure of the beam. In another scheme we propose to use a 30 PeV pion accelerator to create neutrino or anti-neutrino beams. The latter encodes information via the beam CP state as well as timing. Moreover the latter beam requires far less power, and can be accomplished with presently foreseeable technology. Such signals from an advanced civilization, should they exist, will be eminently detectable in existing neutrino detectors.

The ideal neutrino beams

Science.gov (United States)

Lindroos, Mats

2009-06-01

The advance in neutrino oscillation physics is driven by the availability of well characterized and high flux neutrino beams. The three present options for the next generation neutrino oscillation facility are super beams, neutrino factories and beta-beams. A super-beam is a very high intensity classical neutrino beam generated by protons impinging on a target where the neutrinos are generated by the secondary particles decaying in a tunnel down streams of the target. In a neutrino factory the neutrinos are generated from muons decaying in a storage ring with long straight sections pointing towards the detectors. In a beta-beam the neutrinos are also originating from decay in a storage ring but the decaying particles are radioactive ions rather than muons. I will in this presentation review the three options and discuss the pros and cons of each. The present joint design effort for a future high intensity neutrino oscillation in Europe within a common EU supported design study, EURONU, will also be presented. The design study will explore the physics reach, the detectors, the feasibility, the safety issues and the cost for each of the options so that the the community can take a decision on what to build when the facilities presently under exploitation and construction have to be replaced.

Sudbury neutrino observatory

International Nuclear Information System (INIS)

Ewan, G.T.; Evans, H.C.; Lee, H.W.

1986-10-01

This report is a supplement to a report (SNO-85-3 (Sudbury Neutrino Observatory)) which contained the results of a feasibility study on the construction of a deep underground neutrino observatory based on a 1000 ton heavy water Cerenkov detector. Neutrinos carry detailed information in their spectra on the reactions taking place deep in the interstellar interior and also provide information on supernova explosions. In addition to their role as astrophysical probes, a knowledge of the properties of neutrinos is crucial to theories of grand unification. The Sudbury Neutrino Observatory is unique in its high sensitivity to electron neutrinos and its ability to detect all other types of neutrinos of energy greater than 2.2 MeV. The results of the July 1985 study indicated that the project is technically feasible in that the proposed detector can measure the direction and energy of electron neutrinos above 7 MeV and the scientific programs will make significant contributions to physics and astrophysics. This present report contains new information obtained since the 1985 feasibility study. The enhanced conversion of neutrinos in the sun and the new physics that could be learned using the heavy water detector are discussed in the physics section. The other sections will discuss progress in the areas of practical importance in achieving the physics objectives such as new techniques to measure, monitor and remove low levels of radioactivity in detector components, ideas on calibration of the detector and so forth. The section entitled Administration contains a membership list of the working groups within the SNO collaboration

Evidence for neutrino oscillations in the Sudbury Neutrino Observatory

Energy Technology Data Exchange (ETDEWEB)

Marino, Alysia Diane [Univ. of California, Berkeley, CA (United States)

2004-01-01

The Sudbury Neutrino Observatory (SNO) is a large-volume heavy water Cerenkov detector designed to resolve the solar neutrino problem. SNO observes charged-current interactions with electron neutrinos, neutral-current interactions with all active neutrinos, and elastic-scattering interactions primarily with electron neutrinos with some sensitivity to other flavors. This dissertation presents an analysis of the solar neutrino flux observed in SNO in the second phase of operation, while ~2 tonnes of salt (NaCl) were dissolved in the heavy water. The dataset here represents 391 live days of data. Only the events above a visible energy threshold of 5.5 MeV and inside a fiducial volume within 550 cm of the center of the detector are studied. The neutrino flux observed via the charged-current interaction is [1.71 ± 0.065(stat.)±$0.065\\atop{0.068}$(sys.)±0.02(theor.)] x 10⁶cm^-2s^-1, via the elastic-scattering interaction is [2.21±0.22(stat.)±$0.12\\atop{0.11}$(sys.)±0.01(theor.)] x 10⁶cm^-2s^-1, and via the neutral-current interaction is [5.05±0.23(stat.)±$0.31\\atop{0.37}$(sys.)±0.06(theor.)] x 10⁶cm^-2s^-1. The electron-only flux seen via the charged-current interaction is more than 7σ below the total active flux seen via the neutral-current interaction, providing strong evidence that neutrinos are undergoing flavor transformation as they travel from the core of the Sun to the Earth. The most likely origin of the flavor transformation is matter-induced flavor oscillation.

Neutrino masses

International Nuclear Information System (INIS)

Anon.

1986-01-01

Postulated in the early days of quantum mechanics by Wolfgang Pauli to make energy-momentum conservation in nuclear beta decay come out right, the neutrino has never strayed far from physicists' attention. The Moriond Workshop on Massive Neutrinos in Particle Physics and Astrophysics held recently in the French Alps showed that more than half a century after Pauli's prediction, the neutrino stubbornly refuses to yield up all its secrets

Working Group Report: Neutrinos

Energy Technology Data Exchange (ETDEWEB)

de Gouvea, A.; Pitts, K.; Scholberg, K.; Zeller, G. P. [et al.

2013-10-16

This document represents the response of the Intensity Frontier Neutrino Working Group to the Snowmass charge. We summarize the current status of neutrino physics and identify many exciting future opportunities for studying the properties of neutrinos and for addressing important physics and astrophysics questions with neutrinos.

Experimental Neutrino Physics

Energy Technology Data Exchange (ETDEWEB)

Wilkes, Richard Jeffrey [Univ. of Washington, Seattle, WA (United States)

2017-11-15

The University of Washington (UW) HEP neutrino group performed experimental research on the physics of neutrinos, using the capabilities offered by the T2K Experiment and the Super-Kamiokande Neutrino Observatory. The UW group included senior investigator R. J. Wilkes, two PhD students, four MS degree students, and a research engineer, all of whom are members of the international scientific collaborations for T2K and Super-Kamiokande. During the period of support, within T2K we pursued new precision studies sensitive to new physics, going beyond the limits of current measurements of the fundamental neutrino oscillation parameters (mass differences and mixing angles). We began efforts to measure (or significantly determine the absence of) 1 the CP-violating phase parameter δCP and determine the neutrino mass hierarchy. Using the Super-Kamiokande (SK) detector we pursued newly increased precision in measurement of neutrino oscillation parameters with atmospheric neutrinos, and extended the current reach in searches for proton decay, in addition to running the most sensitive supernova watch instrument [Scholberg 2012], performing other astrophysical neutrino studies, and analyzing beam-induced events from T2K. Overall, the research addressed central questions in the field of particle physics. It included the training of graduate students (both PhD and professional MS degree students), and postdoctoral researchers. Undergraduate students also participated as laboratory assistants.

Monochromatic neutrinos from massive fourth generation neutrino annihilation in the Sun and Earth

International Nuclear Information System (INIS)

Belotskij, K.M.; Khlopov, M.Yu.; Shibaev, K.I.

2001-01-01

Accumulation inside the Earth and Sun of heavy (with the mass of 50 GeV) primordial neutrinos and antineutrinos of the fourth generation and their successive annihilation is considered. The minimal estimations of annihilational fluxes of monochromatic e, μ, τ neutrinos (neutrinos and antineutrinos) with the energy of 50 GeV are 4.1·10 -6 cm -2 ·s -1 from the Earth core and 1.1·10 -7 cm -2 ·s -1 from the Sun core. That makes the analysis of underground neutrino observatory data the additional source of information on the existence of massive stable 4th generation neutrino. It is shown that due to the kinetic equilibrium between the influx of the neutrinos and their annihilation the existence of new U(1)-gauge interaction of the 4th generation neutrino does not virtually influence the estimations of annihilational e-, μ-, τ-neutrino fluxes

Neutrino masses and mixings: Big Bang and Supernova nucleosynthesis and neutrino dark matter

International Nuclear Information System (INIS)

Fuller, George M.

1999-01-01

The existence of small mixings between light active and sterile neutrino species could have implications for Big Bang and Supernova Heavy Element Nucleosynthesis. As well, such mixing would force us to abandon cherished constraints on light neutrino Dark Matter. Two proposed 4-neutrino mass and mixing schemes, for example, can both accomodate existing experimental results and lead to elegant solutions to the neutron-deficit problem for r-Process nucleosynthesis from neutrino-heated supernova ejecta. Each of these solutions is based on matter-enhanced (MSW) active-sterile neutrino transformation. In plausible extensions of these schemes to the early universe, Shi and Fuller have shown that relatively light mass (∼200 eV to ∼10 keV) sterile neutrinos produced via active-sterile MSW conversion can have a ''cold'' energy spectrum. Neutrinos produced in this way circumvent the principal problem of light neutrino dark matter and would be, essentially, Cold Dark Matter

CrossRef Neutrino factories

CERN Document Server

Wildner, Elena

2016-01-01

Neutrinos are produced by many processes in our universe. These elusive particles reach the earth having a certain energy permitting them to react with nuclei in detectors that are specifically designed to probe their properties. However, to get higher intensities and higher energy neutrinos for better statistics and better physics reach, the use of accelerators is necessary to advance in the field of neutrino research. To produce neutrinos with an accelerator, one needs to send a high power beam onto a target to get particles or isotopes that produce neutrinos with the required properties, by decay. The parent particles have to be collected and prepared for injection into an accelerating structure. Accelerator-based experiments can tune the energy of the produced neutrinos by boosting and controlling the energy of the parent particle. The produced neutrinos will travel the distance between the source and the detector, generally through earth; the distance the neutrino travels through earth, the energy of the...

Sudbury neutrino observatory proposal

International Nuclear Information System (INIS)

Ewan, G.T.; Evans, H.C.; Lee, H.W.

1987-10-01

This report is a proposal by the Sudbury Neutrino Observatory (SNO) collaboration to develop a world class laboratory for neutrino astrophysics. This observatory would contain a large volume heavy water detector which would have the potential to measure both the electron-neutrino flux from the sun and the total solar neutrino flux independent of neutrino type. It will therefore be possible to test models of solar energy generation and, independently, to search for neutrino oscillations with a sensitivity many orders of magnitude greater than that of terrestrial experiments. It will also be possible to search for spectral distortion produced by neutrino oscillations in the dense matter of the sun. Finally the proposed detector would be sensitive to neutrinos from a stellar collapse and would detect neutrinos of all types thus providing detailed information on the masses of muon- and tau-neutrinos. The neutrino detector would contain 1000 tons of D20 and would be located more than 2000 m below ground in the Creighton mine near Sudbury. The operation and performance of the proposed detector are described and the laboratory design is presented. Construction schedules and responsibilities and the planned program of technical studies by the SNO collaboration are outlined. Finally, the total capital cost is estimated to be $35M Canadian and the annual operating cost, after construction, would be $1.8 M Canadian, including the insurance costs of the heavy water

Medidas de calidad aplicadas a los levantamientos topográficos en Colombia

OpenAIRE

Sabogal Lemus, Carlos Augusto

2016-01-01

Este trabajo documenta la investigación “Medidas de calidad aplicadas a los levantamientos topográficos en Colombia”; la propuesta metodológica de este documento, tiene como objetivo principal la realización de la evaluación de calidad de un conjunto de datos levantados en campo, para lo cual es necesario revisar los antecedentes de la topografía en Colombia, así como los diferentes sistemas de referencia que gobiernan la cartografía del país -- Previo a realizar una evaluación de calidad, se...

Medidas de indices de refração de cristais liquidos esmecticos

OpenAIRE

Kroin, Teodosio

1980-01-01

Dissertação (mestrado) - Universidade Federal de Santa Catarina. Centro de Ciencias Fisicas e Matematicas Mostramos que os cristais líquidos biaxiais podem ter seus índices de refração principais medidos pelo método de Abbe, desde que convenientemente alinhados. Apresentam-se as medidas dos índices de refração das diferentes mesofases e da fase isotrópica do cristal líquido uni-axial 4-butoxibenzilideno-4'- aminoacetofenona em função da temperatura e para três comprimentos de onda. As medi...

Mirror model for sterile neutrinos

International Nuclear Information System (INIS)

Berezinsky, Veniamin; Narayan, Mohan; Vissani, Francesco

2003-01-01

Sterile neutrinos are studied as subdominant contribution to solar neutrino physics. The mirror-matter neutrinos are considered as sterile neutrinos. We use the symmetric mirror model with gravitational communication between mirror and visible sectors. This communication term provides mixing between visible and mirror neutrinos with the basic scale μ=v EW 2 /M Pl =2.5x10 -6 eV, where v EW =174 GeV is the vacuum expectation value of the standard electroweak group and M Pl is the Planckian mass. It is demonstrated that each mass eigenstate of active neutrinos splits into two states separated by small Δm 2 . Unsuppressed oscillations between active and sterile neutrinos (ν a ↔ν s ) occur only in transitions between each of these close pairs ('windows'). These oscillations are characterized by very small Δm 2 and can suppress the flux and distort spectrum of pp-neutrinos in detectable way. The other observable effect is anomalous seasonal variation of neutrino flux, which appears in LMA solution. The considered subdominant neutrino oscillations ν a ↔ν s can reveal itself as big effects in observations of supernova neutrinos and high-energy (HE) neutrinos. In the case of HE neutrinos they can provide a very large diffuse flux of active neutrinos unconstrained by the e-m cascade upper limit

Monochromatic neutrino beams

International Nuclear Information System (INIS)

Bernabeu, Jose; Burguet-Castell, Jordi; Espinoza, Catalina; Lindroos, Mats

2005-01-01

In the last few years spectacular results have been achieved with the demonstration of non vanishing neutrino masses and flavour mixing. The ultimate goal is the understanding of the origin of these properties from new physics. In this road, the last unknown mixing [U e3 ] must be determined. If it is proved to be non-zero, the possibility is open for Charge Conjugation-Parity (CP) violation in the lepton sector. This will require precision experiments with a very intense neutrino source. Here a novel method to create a monochromatic neutrino beam, an old dream for neutrino physics, is proposed based on the recent discovery of nuclei that decay fast through electron capture. Such nuclei will generate a monochromatic directional neutrino beam when decaying at high energy in a storage ring with long straight sections. We also show that the capacity of such a facility to discover new physics is impressive, so that fine tuning of the boosted neutrino energy allows precision measurements of the oscillation parameters even for a [U e3 ] mixing as small as 1 degree. We can thus open a window to the discovery of CP violation in neutrino oscillations

Regulación de las medidas tecnológicas en el derecho comparado. Especial referencia al caso de Estados Unidos, Reino Unido y Australia

Directory of Open Access Journals (Sweden)

Juan Sebastián Sereno Restrepo

2009-11-01

Full Text Available En algunas normas europeas y en precedentes judiciales estadounidenses se encuentran los primeros antecedentes de tutela jurídica a medidas tecnológicas de protección. Sin embargo, sólo a partir de 1996, con del Tratado ompi de Derecho de Autor, se encuentra una consagración expresa de las medidas tecnológicas de protección. La amplia formulación adoptada en el tratado ha sido desarrollada por las legislaciones de los países signatarios de él. En cuanto a la definición, se encuentran los siguientes elementos: producto, dispositivo, componente; aplicación de la medida sobre un bien inmaterial sujeto al régimen de copyright (derecho de autor; la especial finalidad de prevenir o inhibir la infracción al copyright o controlar el acceso; la efectividad; la aplicación de la medida por un sujeto cualificado. La legitimación para el ejercicio del derecho, las modalidades de infracción, las consecuencias civiles y penales y las eximentes de responsabilidad han sido también objeto de tratamiento normativo. Este artículo desarrolla el significado de los complejos elementos enunciados, con ayuda de la jurisprudencia y la doctrina, en tres secciones: estudio de la función práctica de las medias tecnológicas y su historia legislativa; definición de medida y condiciones para su protección; modalidades de infracción y eximentes de responsabilidad

Regulación de las medidas tecnológicas en el derecho comparado. Especial referencia al caso de Estados Unidos, Reino Unido y Australia

Directory of Open Access Journals (Sweden)

Juan Sebastián Sereno Restrepo

2009-11-01

Full Text Available En algunas normas europeas y en precedentes judiciales estadounidenses se encuentran los primeros antecedentes de tutela jurídica a medidas tecnológicas de protección. Sin embargo, sólo a partir de 1996, con del Tratado ompi de Derecho de Autor, se encuentra una consagración expresa de las medidas tecnológicas de protección. La amplia formulación adoptada en el tratado ha sido desarrollada por las legislaciones de los países signatarios de él. En cuanto a la definición, se encuentran los siguientes elementos: producto, dispositivo, componente; aplicación de la medida sobre un bien inmaterial sujeto al régimen de copyright (derecho de autor; la especial finalidad de prevenir o inhibir la infracción al copyright o controlar el acceso; la efectividad; la aplicación de la medida por un sujeto cualificado. La legitimación para el ejercicio del derecho, las modalidades de infracción, las consecuencias civiles y penales y las eximentes de responsabilidad han sido también objeto de tratamiento normativo. Este artículo desarrolla el significado de los complejos elementos enunciados, con ayuda de la jurisprudencia y la doctrina, en tres secciones: estudio de la función práctica de las medias tecnológicas y su historia legislativa; definición de medida y condiciones para su protección; modalidades de infracción y eximentes de responsabilidad.

Experimental Neutrino Physics: Final Report

Energy Technology Data Exchange (ETDEWEB)

Lane, Charles E.; Maricic, Jelena

2012-09-05

Experimental studies of neutrino properties, with particular emphasis on neutrino oscillation, mass and mixing parameters. This research was pursued by means of underground detectors for reactor anti-neutrinos, measuring the flux and energy spectra of the neutrinos. More recent investigations have been aimed and developing detector technologies for a long-baseline neutrino experiment (LBNE) using a neutrino beam from Fermilab.

Neutrino physics present and future

CERN Multimedia

CERN. Geneva

2006-01-01

Our understanding of neutrinos has been revolutionized by the discovery that they have nonzero masses and very large mixing. We will explain the phenomenology of massive neutrinos, including neutrino oscillation in vacuum and in matter, and the physics of neutrinos that are their own antiparticles. We will review the evidence for neutrino masses and mixing, and summarize what has been learned about the neutrinos so far. Identifying the very interesting open questions raised by the discovery of neutrino mass, we will discuss how these questions may be answered through future experiments. Finally, we will consider the possibility that CP violation by neutrinos is the key to understanding the matter-antimatter asymmetry of the universe, and discuss the see-saw theory of why neutrino masses are so tiny.

Two lectures on neutrinos

International Nuclear Information System (INIS)

Ramond, P.

1992-01-01

These notes are based on two lectures delivered at the School. A general description of neutrinos is presented, first in purely kinematic terms, then in the context of the Standard Model, focusing on the role of the global lepton numbers. Standard Model extensions with massive neutrinos are cataloged. Several popular mass matrices for neutrinos, and their consequences are presented. They proceed to give an extended discussion of neutrino oscillations in matter, and apply the results to the solar neutrinos

Neutrino mass matrix

International Nuclear Information System (INIS)

Strobel, E.L.

1985-01-01

Given the many conflicting experimental results, examination is made of the neutrino mass matrix in order to determine possible masses and mixings. It is assumed that the Dirac mass matrix for the electron, muon, and tau neutrinos is similar in form to those of the quarks and charged leptons, and that the smallness of the observed neutrino masses results from the Gell-Mann-Ramond-Slansky mechanism. Analysis of masses and mixings for the neutrinos is performed using general structures for the Majorana mass matrix. It is shown that if certain tentative experimental results concerning the neutrino masses and mixing angles are confirmed, significant limitations may be placed on the Majorana mass matrix. The most satisfactory simple assumption concerning the Majorana mass matrix is that it is approximately proportional to the Dirac mass matrix. A very recent experimental neutrino mass result and its implications are discussed. Some general properties of matrices with structure similar to the Dirac mass matrices are discussed

NEUTRINO MASS

OpenAIRE

Kayser, Boris

1988-01-01

This is a review article about the most recent developments on the field of neutrino mass. The first part of the review introduces the idea of neutrino masses and mixing angles, summarizes the most recent experimental data then discusses the experimental prospects and challenges in this area. The second part of the review discusses the implications of these results for particle physics and cosmology, including the origin of neutrino mass, the see-saw mechanism and sequential dominance, and la...

The Deep Underground Neutrino Experiment: The precision era of neutrino physics

Energy Technology Data Exchange (ETDEWEB)

Kemp, E. [Gleb Wataghin Institute of Physics, Universidade de Campinas - UNICAMP, Campinas Brazil

2017-12-01

The last decade was remarkable for neutrino physics. In particular, the phenomenon of neutrino flavor oscillations has been firmly established by a series of independent measurements. All parameters of the neutrino mixing are now known, and we have the elements to plan a judicious exploration of new scenarios that are opened by these recent advances. With precise measurements, we can test the three-neutrino paradigm, neutrino mass hierarchy, and charge conjugation parity (CP) asymmetry in the lepton sector. The future long-baseline experiments are considered to be a fundamental tool to deepen our knowledge of electroweak interactions. The Deep Underground Neutrino Experiment (DUNE) will detect a broadband neutrino beam from Fermilab in an underground massive liquid argon time-projection chamber at an L/E of about 103 km GeV-1 to reach good sensitivity for CP-phase measurements and the determination of the mass hierarchy. The dimensions and the depth of the far detector also create an excellent opportunity to look for rare signals like proton decay to study violation of the baryonic number, as well as supernova neutrino bursts, broadening the scope of the experiment to astrophysics and associated impacts in cosmology. In this paper, we discuss the physics motivations and the main experimental features of the DUNE project required to reach its scientific goals.

Estudo da confiabilidade e validade da utilização do hidropletismômetro para medida de edema no tornozelo Study of the reliability and validity of the water plethysmographer for use in measurement of the edema at the ankle/foot

Directory of Open Access Journals (Sweden)

Ian Lara Lamounier Andrade

2011-03-01

Full Text Available Instrumentos confiáveis e válidos são necessários para avaliar a efetividade das técnicas de reabilitação. O objetivo deste estudo foi avaliar a confiabilidade e a validade do Hidropletismômetro. Quatorze sujeitos com idade entre 18 e 59 anos foram selecionados para participar do estudo. Os tornozelos foram avaliados por dois examinadores treinados com o Hidropletismômetro. Três medidas de cada tornozelo foram obtidas pelos examinadores de forma aleatória para investigar a confiabilidade intra e inter-examinadores. Foram também obtidas vinte e seis medidas com o Hidropletismômetro e comparadas com as medidas obtidas com o Deslocador de Água considerado "padrão ouro", através de provetas de vidro graduadas de 10 ml a 1000 ml. A confiabilidade intra e inter-examinadores foi realizada através do Coeficiente de Correlação Intraclasse (CCI e a validade através do teste t pareado. O Coeficiente de Correlação de Pearson foi utilizado para estabelecer a associação entre os dois instrumentos. Os dados demonstraram níveis de confiabilidade intra e inter-examinadores com (CCI3,1 = 0,99 e (CCI3,2 = 0,99, respectivamente. Nenhuma diferença foi encontrada entre as medidas obtidas com o Hidropletismômetro e as obtidas com as provetas (p=0,404. A Correlação de Coeficiente de Pearson mostrou alta magnitute e nível de significância entre as medidas (r=1,0; pReliable and valid instruments are necessary to evaluate the effectiveness of the rehabilitation techniques.The objective this study was to evaluate the reliability and the validity of the water plethysmography. Fourteen subjects between the ages of 18 and 59 years were selected to participate in the study. Ankles were assessed by two trained examiners with the water plethysmography. Three measures of each ankle were obtained by the two investigators to evaluate intra- and inter-raters reliability. Twenty-six measures were obtained with the water plethysmography and compared with

Relic right-handed Dirac neutrinos and implications for detection of cosmic neutrino background

Directory of Open Access Journals (Sweden)

Jue Zhang

2016-02-01

Full Text Available It remains to be determined experimentally if massive neutrinos are Majorana or Dirac particles. In this connection, it has been recently suggested that the detection of cosmic neutrino background of left-handed neutrinos νL and right-handed antineutrinos ν‾R in future experiments of neutrino capture on beta-decaying nuclei (e.g., νe+H3→He3+e− for the PTOLEMY experiment is likely to distinguish between Majorana and Dirac neutrinos, since the capture rate is twice larger in the former case. In this paper, we investigate the possible impact of right-handed neutrinos on the capture rate, assuming that massive neutrinos are Dirac particles and both right-handed neutrinos νR and left-handed antineutrinos ν‾L can be efficiently produced in the early Universe. It turns out that the capture rate can be enhanced at most by 28% due to the presence of relic νR and ν‾L with a total number density of 95 cm−3, which should be compared to the number density 336 cm−3 of cosmic neutrino background. The enhancement has actually been limited by the latest cosmological and astrophysical bounds on the effective number of neutrino generations Neff=3.14−0.43+0.44 at the 95% confidence level. For illustration, two possible scenarios have been proposed for thermal production of right-handed neutrinos in the early Universe.

Towards neutrino astronomy

International Nuclear Information System (INIS)

Lagage, P.O.; Spiro, M.

1985-01-01

Neutrino sources are numerous and varied; the sun, a supernova explosion, the cosmic radiation interaction with interstellar medium are neutrino or antineutrino sources. The aim of this article is to overview the international projects of neutrino detection while giving the preference to the experimental side of the detection [fr

Can neutrino-electron scattering tell us whether neutrinos are Dirac or Majorana particles?

International Nuclear Information System (INIS)

Kayser, B.

1988-04-01

There has recently been interest in the possibility that neutrino-electron scattering experiments could determine whether neutrinos are Dirac or Majorana particles by providing information on their electromagnetic structure. We try to explain why studies of neutrino electromagnetic structure actually cannot distinguish between Dirac and Majorana neutrinos. 9 refs

Accelerator and Technical Sector Seminar: Future neutrino facilities: the neutrino factory

CERN Multimedia

2012-01-01

Thursday 19.January 2012 at 14:15  -  IT Auditorium (bldg. 31 3-004) Future neutrino facilities: the neutrino factory by Gersende Prior / University of Geneva and CERN EN/MEF The neutrino factory is one of the proposed designs for a future intense neutrino beam facility. In its current layout, a high-power proton beam impinges on an Hg jet target producing pions, decaying in turn into muons. In order to reduce the particle beam emittance, the muon transverse momentum is reduced through ionization cooling by a technically demanding set-up made of closely-packed RF cavities alternating with absorbers. In this talk I will present the motivation for building an intense neutrino beam and some of the proposed neutrino facilities' design. I will discuss the challenges inherent to the cooling of muons, possible optimization of the current baseline and the on-going R&D. ________________ ATS Seminars Organisers: H. Burkhardt (BE), S. Sgobba (EN), G. deRijk (TE)

Neutrino mixing and lepton CP-phase in neutrino oscillations

International Nuclear Information System (INIS)

Ryzhikh, D.A.; Ter-Martirosyan, K.A.

2001-01-01

One studied oscillations of the Dirac neutrinos belonging to three generations in vacuum with regard to the effect of the lepton CP-breaking phase on them in the matrix of lepton mixing (analogue of the quark CP-phase). In the general form one obtained formulae for probabilities of transition of neutrino of one kind to another at oscillations depending on three angles of mixing and on CP-phase. It was pointed that when measuring oscillation average probabilities of transition of neutrino of one kind to another one might in principle, restore the value of lepton CP-phase. Manifestation of CP-phase in the form of deviation of the values of probabilities of direct neutrino transition from reverse one is the effect practically escaping observation [ru

Solar neutrino

Energy Technology Data Exchange (ETDEWEB)

Sugimoto, D [Tokyo Univ. (Japan). Coll. of General Education

1975-01-01

The measurement of solar neutrino was performed by using the reaction /sup 37/cl+..nu..sub(e)..-->../sup 37/Ar+e/sup -/ by Davis et al. The argon gas produced through the above mentioned reaction in a tank containing 610 ton of C/sub 2/Cl/sub 4/ was collected and measured. The rate of production of /sup 37/Ar was 0.13+-0.20/day, and the net production rate by the solar neutrino was 0.06+-0.20/day, being corrected for background. This value corresponds to 0.5+-1.0 SNU. Theoretical calculation with the model of spherically symmetric solar development gave an expected value of 5.6 SNU, which is in contradiction with the experimental value. Reason of this discrepancy was considered. The possibility of decay of neutrino to the other particles with weak interaction is very slight. Various models of the sun were investigated, but the results were still inconsistent with the experiment. The mixing of matters in the sun may cause the reduction of neutrino. If He gas comes to the center of the sun by mixing, the reaction, /sup 3/He+/sup 3/He, progresses excessively at the center, and it produces the expansion of the core of the sun. Then, the temperature drops and the neutrino is reduced. Various models which can explain the neutrino of less than ISNU have been presented. However, other theory says that the reduction of neutrino is not expected even if the mixing is considered. A problem concerning the mixing is whether the thermal instability which causes the mixing exists. (Kato, T.).

Neutrino mass

International Nuclear Information System (INIS)

Robertson, R.G.H.

1992-01-01

Despite intensive experimental work since the neutrino's existence was proposed by Pauli 60 years ago, and its first observation by Reines and Cowan almost 40 years ago, the neutrino's fundamental properties remain elusive. Among those properties are the masses of the three known flavors, properties under charge conjugation, parity and time-reversal, and static and dynamic electromagnetic moments. Mass is perhaps the most fundamental, as it constrains the other properties. The present status of the search for neutrino mass is briefly reviewed

Neutrino Oscillation Physics

International Nuclear Information System (INIS)

Kayser, Boris

2014-01-01

To complement the neutrino-physics lectures given at the 2011 International School on Astro Particle Physics devoted to Neutrino Physics and Astrophysics (ISAPP 2011; Varenna, Italy), at the 2011 European School of High Energy Physics (ESHEP 2011; Cheila Gradistei, Romania), and, in modified form, at other summer schools, we present here a written description of the physics of neutrino oscillation. This description is centered on a new way of deriving the oscillation probability. We also provide a brief guide to references relevant to topics other than neutrino oscillation that were covered in the lectures

Neutrino Oscillation Physics

Energy Technology Data Exchange (ETDEWEB)

Kayser, Boris [Fermilab (United States)

2014-07-01

To complement the neutrino-physics lectures given at the 2011 International School on Astro Particle Physics devoted to Neutrino Physics and Astrophysics (ISAPP 2011; Varenna, Italy), at the 2011 European School of High Energy Physics (ESHEP 2011; Cheila Gradistei, Romania), and, in modified form, at other summer schools, we present here a written description of the physics of neutrino oscillation. This description is centered on a new way of deriving the oscillation probability. We also provide a brief guide to references relevant to topics other than neutrino oscillation that were covered in the lectures.

Solar neutrino experiments

International Nuclear Information System (INIS)

Hampel, W.

1996-01-01

The present status of experimental solar neutrino research is reviewed. Updated results from the Homestake, Kamiokande, GALLEX and SAGE detectors all show a deficit when compared to recent standard solar model calculations. Two of these detectors, GALLEX and SAGE, have recently been checked with artificial 51 Cr neutrino sources. It is shown that astrophysical scenarios to solve the solar neutrino problems are not favoured by the data. There is hope that the results of forthcoming solar neutrino experiments can provide the answers to the open questions. (author) 6 figs., 3 tabs., 36 refs

Solar neutrino experiments

Energy Technology Data Exchange (ETDEWEB)

Hampel, W [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany)

1996-11-01

The present status of experimental solar neutrino research is reviewed. Updated results from the Homestake, Kamiokande, GALLEX and SAGE detectors all show a deficit when compared to recent standard solar model calculations. Two of these detectors, GALLEX and SAGE, have recently been checked with artificial {sup 51}Cr neutrino sources. It is shown that astrophysical scenarios to solve the solar neutrino problems are not favoured by the data. There is hope that the results of forthcoming solar neutrino experiments can provide the answers to the open questions. (author) 6 figs., 3 tabs., 36 refs.

Avaliação da inteligência emocional: a relação entre medidas de desempenho e de autorrelato

Directory of Open Access Journals (Sweden)

Ana Cristina Fontes Costa

Full Text Available Apresenta-se a adaptação e validação do Teste de Vocabulário Emocional (TVE ao contexto português, uma medida de desempenho de inteligência emocional, explorando as suas qualidades psicométricas e a validade de critério e convergente com uma medida de autorrelato, o Questionário de Competência Emocional - Revisto (QCE-R. O TVE, com 35 itens, desenvolvido por Takšic, Herambasic e Velemir (2003 no contexto croata, mede a capacidade para compreender emoções. A amostra incluiu 682 alunos do 10.º ano, entre 14 e 21 anos (M = 15,5; DP = 0,77 de diferentes cursos científico-humanísticos. Genericamente, o TVE revelou boas qualidades psicométricas, tendo-se correlacionado positivamente com o rendimento académico e evidenciado maior capacidade para o predizer do que o QCE-R, com o qual não estabeleceu qualquer associação.

LSND neutrino oscillation results

International Nuclear Information System (INIS)

Louis, W.C.

1996-01-01

In the past several years, a number of experiments have searched for neutrino oscillations, where a neutrino of one type (say bar ν μ ) spontaneously transforms into a neutrino of another type (say bar ν e ). For this phenomenon to occur, neutrinos must be massive and the apparent conservation law of lepton families must be violated. In 1995 the LSND experiment published data showing candidate events that are consistent with bar ν μ oscillations. Additional data are reported here which provide stronger evidence for neutrino oscillations

Updated determination of the solar neutrino fluxes from solar neutrino data

Energy Technology Data Exchange (ETDEWEB)

Bergström, Johannes [Departament d’Estructura i Constituents de la Matèria and Institut de Ciencies del Cosmos,Universitat de Barcelona, Diagonal 647, E-08028 Barcelona (Spain); Gonzalez-Garcia, M. C. [Departament d’Estructura i Constituents de la Matèria and Institut de Ciencies del Cosmos,Universitat de Barcelona, Diagonal 647, E-08028 Barcelona (Spain); Institució Catalana de Recerca i Estudis Avançats (ICREA) (Spain); C.N. Yang Institute for Theoretical Physics,State University of New York at Stony Brook, Stony Brook, NY 11794-3840 (United States); Maltoni, Michele [Instituto de Física Teórica UAM/CSIC,Calle de Nicolás Cabrera 13-15, Universidad Autónoma de Madrid,Cantoblanco, E-28049 Madrid (Spain); Peña-Garay, Carlos [Instituto de Física Corpuscular (IFIC), CSIC and Universitat de Valencia,Calle Catedrático José Beltrán, 2, E-46090 Paterna, Valencia (Spain); Serenelli, Aldo M. [Institut de Ciencies de l’Espai (ICE-CSIC/IEEC),Campus UAB, Carrer de Can Magrans s/n, 08193 Cerdanyola del Valls (Spain); Song, Ningqiang [C.N. Yang Institute for Theoretical Physics,State University of New York at Stony Brook, Stony Brook, NY 11794-3840 (United States)

2016-03-18

We present an update of the determination of the solar neutrino fluxes from a global analysis of the solar and terrestrial neutrino data in the framework of three-neutrino mixing. Using a Bayesian analysis we reconstruct the posterior probability distribution function for the eight normalization parameters of the solar neutrino fluxes plus the relevant masses and mixing, with and without imposing the luminosity constraint. We then use these results to compare the description provided by different Standard Solar Models. Our results show that, at present, both models with low and high metallicity can describe the data with equivalent statistical agreement. We also argue that even with the present experimental precision the solar neutrino data have the potential to improve the accuracy of the solar model predictions.

Neutrinos at CERN

International Nuclear Information System (INIS)

Anon.

1993-01-01

CERN's long and distinguished neutrino tradition began in 1958 at the then new 500 MeV synchrocyclotron (SC) with the first observation of the decay of a charged pion into an electron and a neutrino. At that time, the first ideas on the special (vector/axial vector) structure of the weak interactions had been put forward by Feynman and Gell-Mann and by Marshak and Sudarshan, but the continual non-observation of that charged pion decay was holding up progress. This decay is only one part in ten thousand, and is masked by the dominant muon-neutrino channel. A special telescope was built to pick up the high energy electrons from the pion decay. In 1962 came another SC neutrino success, with the first measurement of the decay of a charged pion into a neutral one, with emission of an electron and a neutrino. Meanwhile the main thrust of CERN's neutrino effort was taking shape at the PS. By the close of 1960, CERN had decided to attack neutrino physics using several detectors - a 1m heavy liquid bubble chamber from Andre Lagarrigue's team in Paris, a CERN 1 m heavy liquid bubble chamber, and a hybrid chamber/counter from a group led by Helmut Faissner

Active-sterile neutrino conversion: consequences for the r-process and supernova neutrino detection

Science.gov (United States)

Fetter, J.; McLaughlin, G. C.; Balantekin, A. B.; Fuller, G. M.

2003-02-01

We examine active-sterile neutrino conversion in the late time post-core-bounce supernova environment. By including the effect of feedback on the Mikheyev-Smirnov-Wolfenstein (MSW) conversion potential, we obtain a large range of neutrino mixing parameters which produce a favorable environment for the r-process. We look at the signature of this effect in the current generation of neutrino detectors now coming on line. We also investigate the impact of the neutrino-neutrino forward-scattering-induced potential on the MSW conversion.

Resolving neutrino mass hierarchy from supernova (anti)neutrino-nucleus reactions

Science.gov (United States)

Vale, Deni; Paar, Nils

2015-10-01

Recently a hybrid method has been introduced to determine neutrino mass hierarchy by simultaneous measurements of detector responses induced by antineutrino and neutrino fluxes from accretion and cooling phase of type II supernova. The (anti)neutrino-nucleus cross sections for 12C, 16O, 56Fe and 208Pb are calculated in the framework of relativistic nuclear energy density functional and weak interaction Hamiltonian, while the cross sections for inelastic scattering on free protons in mineral oil and water, p (v¯e,e+)n are obtained using heavy-baryon chiral perturbation theory. The simulations of (anti)neutrino fluxes emitted from a proto-neutron star in a core-collapse supernova include collective and Mikheyev-Smirnov-Wolfenstein effects inside star. It is shown that simultaneous use of ve/v¯e detectors with different target material allow to determine the neutrino mass hierarchy from the ratios of ve/v¯e induced particle emissions. The hybrid method favors detectors with heavier target nuclei (208Pb) for the neutrino sector, while for antineutrinos the use of free protons in mineral oil and water is more appropriate.

Visible neutrino decay at DUNE

Energy Technology Data Exchange (ETDEWEB)

Coloma, Pilar [Fermilab; Peres, Orlando G. [ICTP, Trieste

2017-05-09

If the heaviest neutrino mass eigenstate is unstable, its decay modes could include lighter neutrino eigenstates. In this case part of the decay products could be visible, as they would interact at neutrino detectors via mixing. At neutrino oscillation experiments, a characteristic signature of such \\emph{visible neutrino decay} would be an apparent excess of events at low energies. We focus on a simple phenomenological model in which the heaviest neutrino decays as $\

Effects of neutrino oscillations on nucleosynthesis and neutrino signals for an 18 M⊙ supernova model

Science.gov (United States)

Wu, Meng-Ru; Qian, Yong-Zhong; Martínez-Pinedo, Gabriel; Fischer, Tobias; Huther, Lutz

2015-03-01

In this paper, we explore the effects of neutrino flavor oscillations on supernova nucleosynthesis and on the neutrino signals. Our study is based on detailed information about the neutrino spectra and their time evolution from a spherically symmetric supernova model for an 18 M⊙ progenitor. We find that collective neutrino oscillations are not only sensitive to the detailed neutrino energy and angular distributions at emission, but also to the time evolution of both the neutrino spectra and the electron density profile. We apply the results of neutrino oscillations to study the impact on supernova nucleosynthesis and on the neutrino signals from a Galactic supernova. We show that in our supernova model, collective neutrino oscillations enhance the production of rare isotopes 138La and 180Ta but have little impact on the ν p -process nucleosynthesis. In addition, the adiabatic Mikheyev-Smirnov-Wolfenstein flavor transformation, which occurs in the C /O and He shells of the supernova, may affect the production of light nuclei such as 7Li and 11B. For the neutrino signals, we calculate the rate of neutrino events in the Super-Kamiokande detector and in a hypothetical liquid argon detector. Our results suggest the possibility of using the time profiles of the events in both detectors, along with the spectral information of the detected neutrinos, to infer the neutrino mass hierarchy.

Search for sterile neutrinos in muon neutrino disappearance mode at FNAL

International Nuclear Information System (INIS)

Anokhina, A.; Dzhatdoev, T.; Morgunova, O.; Roganova, T.; Bagulya, A.; Chernyavskiy, M.; Dalkarov, O.; Mingazheva, R.; Shchedrina, T.; Starkov, N.; Vladymyrov, M.; Benettoni, M.; Dal Corso, F.; Dusini, S.; Lippi, I.; Longhin, A.; Bernardini, P.; Mancarella, G.; Marsella, G.; Brugnera, R.; Garfagnini, A.; Medinaceli, E.; Roda, M.; Sirignano, C.; Calabrese, M.; Fiore, G.; Surdo, A.; Cecchetti, A.; Orecchini, D.; Paoloni, A.; Cecchini, S.; Di Ferdinando, D.; Guerzoni, M.; Laurenti, G.; Mandrioli, G.; Mauri, N.; Patrizii, L.; Pozzato, M.; Sahnoun, Z.; Sirri, G.; Togo, V.; Del Prete, A.; Papadia, G.; De Robertis, G.; Fini, R.A.; Loddo, F.; Pastore, A.; De Serio, M.; Paparella, L.; Simone, S.; Klicek, B.; Jakovcic, K.; Malenica, M.; Stipcevic, M.; Kose, U.; Nessi, M.; Margiotta, A.; Pasqualini, L.; Spurio, M.; Muciaccia, M.T.; Polukhina, N.; Rosa, G.; Stanco, L.; Tenti, M.

2017-01-01

The NESSiE Collaboration has been setup to undertake a conclusive experiment to clarify the muon-neutrino disappearance measurements at short baselines in order to put severe constraints to models with more than the three-standard neutrinos. To this aim the current FNAL-Booster neutrino beam for a Short-Baseline experiment was carefully evaluated by considering the use of magnetic spectrometers at two sites, near and far ones. The detector locations were studied, together with the achievable performances of two OPERA-like spectrometers. The study was constrained by the availability of existing hardware and a time-schedule compatible with the undergoing project of multi-site Liquid-Argon detectors at FNAL. The settled physics case and the kind of proposed experiment on the Booster neutrino beam would definitively clarify the existing tension between the ν μ disappearance and the ν e appearance/disappearance at the eV mass scale. In the context of neutrino oscillations the measurement of ν μ disappearance is a robust and fast approach to either reject or discover new neutrino states at the eV mass scale. We discuss an experimental program able to extend by more than one order of magnitude (for neutrino disappearance) and by almost one order of magnitude (for antineutrino disappearance) the present range of sensitivity for the mixing angle between standard and sterile neutrinos. These extensions are larger than those achieved in any other proposal presented so far. (orig.)

Search for sterile neutrinos in muon neutrino disappearance mode at FNAL

Science.gov (United States)

Anokhina, A.; Bagulya, A.; Benettoni, M.; Bernardini, P.; Brugnera, R.; Calabrese, M.; Cecchetti, A.; Cecchini, S.; Chernyavskiy, M.; Dal Corso, F.; Dalkarov, O.; Del Prete, A.; De Robertis, G.; De Serio, M.; Di Ferdinando, D.; Dusini, S.; Dzhatdoev, T.; Fini, R. A.; Fiore, G.; Garfagnini, A.; Guerzoni, M.; Klicek, B.; Kose, U.; Jakovcic, K.; Laurenti, G.; Lippi, I.; Loddo, F.; Longhin, A.; Malenica, M.; Mancarella, G.; Mandrioli, G.; Margiotta, A.; Marsella, G.; Mauri, N.; Medinaceli, E.; Mingazheva, R.; Morgunova, O.; Muciaccia, M. T.; Nessi, M.; Orecchini, D.; Paoloni, A.; Papadia, G.; Paparella, L.; Pasqualini, L.; Pastore, A.; Patrizii, L.; Polukhina, N.; Pozzato, M.; Roda, M.; Roganova, T.; Rosa, G.; Sahnoun, Z.; Shchedrina, T.; Simone, S.; Sirignano, C.; Sirri, G.; Spurio, M.; Stanco, L.; Starkov, N.; Stipcevic, M.; Surdo, A.; Tenti, M.; Togo, V.; Vladymyrov, M.

2017-01-01

The NESSiE Collaboration has been setup to undertake a conclusive experiment to clarify the muon-neutrino disappearance measurements at short baselines in order to put severe constraints to models with more than the three-standard neutrinos. To this aim the current FNAL-Booster neutrino beam for a Short-Baseline experiment was carefully evaluated by considering the use of magnetic spectrometers at two sites, near and far ones. The detector locations were studied, together with the achievable performances of two OPERA-like spectrometers. The study was constrained by the availability of existing hardware and a time-schedule compatible with the undergoing project of multi-site Liquid-Argon detectors at FNAL. The settled physics case and the kind of proposed experiment on the Booster neutrino beam would definitively clarify the existing tension between the ν _{μ } disappearance and the ν e appearance/disappearance at the eV mass scale. In the context of neutrino oscillations the measurement of ν _{μ } disappearance is a robust and fast approach to either reject or discover new neutrino states at the eV mass scale. We discuss an experimental program able to extend by more than one order of magnitude (for neutrino disappearance) and by almost one order of magnitude (for antineutrino disappearance) the present range of sensitivity for the mixing angle between standard and sterile neutrinos. These extensions are larger than those achieved in any other proposal presented so far.

Search for sterile neutrinos in muon neutrino disappearance mode at FNAL

Energy Technology Data Exchange (ETDEWEB)

Anokhina, A.; Dzhatdoev, T.; Morgunova, O.; Roganova, T. [Lomonosov Moscow State University (MSU SINP), Moscow (Russian Federation); Bagulya, A.; Chernyavskiy, M.; Dalkarov, O.; Mingazheva, R.; Shchedrina, T.; Starkov, N.; Vladymyrov, M. [Lebedev Physical Institute of Russian Academy of Sciences, Moscow (Russian Federation); Benettoni, M.; Dal Corso, F.; Dusini, S.; Lippi, I.; Longhin, A. [INFN, Sezione di Padova, Padua (Italy); Bernardini, P.; Mancarella, G.; Marsella, G. [Universita del Salento, Dipartimento di Matematica e Fisica, Lecce (Italy); INFN, Sezione di Lecce, Lecce (Italy); Brugnera, R.; Garfagnini, A.; Medinaceli, E.; Roda, M.; Sirignano, C. [INFN, Sezione di Padova, Padua (Italy); Universita di Padova, Dipartimento di Fisica e Astronomia, Padua (Italy); Calabrese, M.; Fiore, G.; Surdo, A. [INFN, Sezione di Lecce, Lecce (Italy); Cecchetti, A.; Orecchini, D.; Paoloni, A. [INFN, Laboratori Nazionali di Frascati, Frascati, RM (Italy); Cecchini, S.; Di Ferdinando, D.; Guerzoni, M.; Laurenti, G.; Mandrioli, G.; Mauri, N.; Patrizii, L.; Pozzato, M.; Sahnoun, Z.; Sirri, G.; Togo, V. [INFN, Sezione di Bologna, Bologna (Italy); Del Prete, A.; Papadia, G. [INFN, Sezione di Lecce, Lecce (Italy); Universita del Salento, Dipartimento di Ingegneria dell' Innovazione, Lecce (Italy); De Robertis, G.; Fini, R.A.; Loddo, F.; Pastore, A. [INFN, Sezione di Bari, Bari (Italy); De Serio, M.; Paparella, L.; Simone, S. [INFN, Sezione di Bari, Bari (Italy); Universita di Bari, Dipartimento di Fisica, Bari (Italy); Klicek, B.; Jakovcic, K.; Malenica, M.; Stipcevic, M. [Rudjer Boskovic Institute, Zagreb (Croatia); Kose, U.; Nessi, M. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Margiotta, A.; Pasqualini, L.; Spurio, M. [INFN, Sezione di Bologna, Bologna (Italy); Universita di Bologna, Dipartimento di Fisica e Astronomia, Bologna (Italy); Muciaccia, M.T. [Universita di Bari, Dipartimento di Fisica, Bari (Italy); Polukhina, N. [Lebedev Physical Institute of Russian Academy of Sciences, Moscow (Russian Federation); National Research Nuclear University MEPhI, Moscow (Russian Federation); Rosa, G. [INFN, Sezione di Roma, Rome (Italy); Stanco, L. [INFN, Sezione di Padova, Padua (Italy); Tenti, M. [Universita di Bologna, Dipartimento di Fisica e Astronomia, Bologna (Italy); NFN-CNAF, Bologna (Italy)

2017-01-15

The NESSiE Collaboration has been setup to undertake a conclusive experiment to clarify the muon-neutrino disappearance measurements at short baselines in order to put severe constraints to models with more than the three-standard neutrinos. To this aim the current FNAL-Booster neutrino beam for a Short-Baseline experiment was carefully evaluated by considering the use of magnetic spectrometers at two sites, near and far ones. The detector locations were studied, together with the achievable performances of two OPERA-like spectrometers. The study was constrained by the availability of existing hardware and a time-schedule compatible with the undergoing project of multi-site Liquid-Argon detectors at FNAL. The settled physics case and the kind of proposed experiment on the Booster neutrino beam would definitively clarify the existing tension between the ν{sub μ} disappearance and the ν{sub e} appearance/disappearance at the eV mass scale. In the context of neutrino oscillations the measurement of ν{sub μ} disappearance is a robust and fast approach to either reject or discover new neutrino states at the eV mass scale. We discuss an experimental program able to extend by more than one order of magnitude (for neutrino disappearance) and by almost one order of magnitude (for antineutrino disappearance) the present range of sensitivity for the mixing angle between standard and sterile neutrinos. These extensions are larger than those achieved in any other proposal presented so far. (orig.)

Exploring new features of neutrino oscillations with very low energy monoenergetic neutrinos

CERN Document Server

Vergados, J D

2010-01-01

In the present work we propose to study neutrino oscillations employing sources of monoenergetic neutrinos following electron capture by the nucleus. Since the neutrino energy is very low the smaller of the two oscillation lengths, L23, appearing in this electronic neutrino disappearance experiment can be so small that the full oscillation can take place inside the detector and one may determine very accurately the neutrino oscillation parameters. Since in this case the oscillation probability is proportional to theta13, one can measure or set a better limit on the unknown parameter theta13. This is quite important, since, if this mixing angle vanishes, there is not going to be CP violation in the leptonic sector. The best way to detect it is by measuring electron recoils in neutrino-electron scattering. One, however, has to pay the price that the expected counting rates are very small. Thus one needs a very intensive neutrino source and a large detector with as low as possible energy threshold and high energ...

Neutrino burst from SN1987A and the solar-neutrino puzzle

International Nuclear Information System (INIS)

Arafune, J.; Fukugita, M.; Yanagida, T.; Yoshimura, M.

1987-01-01

The prompt ν/sub e/ signal from the supernova explosion in the Large Magellanic Cloud presumably detected by Kamiokande II does not necessarily mean that the Mikheyev-Smirnov-Wolfenstein effect on the solar-neutrino flux is not operative. The electron neutrino, once rotated to a different-flavor neutrino in the progenitor star, can come back via the matter-oscillation effect in the Earth, or a residual ν/sub e/ flux from the progenitor can directly hit the detector, saving the Mikheyev-Smirnov-Wolfenstein explanation of the solar-neutrino problem for a range of mixing parameters

Beam and experiments summary [neutrino studies

CERN Document Server

Blondel, A; Campanelli, M; Cervera-Villanueva, Anselmo; Cline, David B; Collot, J; De Jong, M; Donini, Andrea; Dydak, Friedrich; Edgecock, R; Gavela-Legazpi, Maria Belen; Gómez-Cadenas, J J; González-Garciá, M Concepción; Gruber, P; Harris, D A; Hernández, Pilar; Kuno, Y; Litchfield, P J; McFarland, K; Mena, O; Migliozzi, P; Palladino, Vittorio; Panman, J; Papadopoulos, I M; Para, A; Peña-Garay, C; Pérez, P; Rigolin, Stefano; Romanino, Andrea; Rubbia, André; Strolin, P; Wojcicki, S G

2000-01-01

The discovery of neutrino oscillations marks a major milestone in the history of neutrino physics, and opens a new window to the still mysterious origin of masses and flavour mixing. Many current and forthcoming experiments will. Answer open questions; however, a major step forward, up to and possibly including CP violation in the neutrino-mixing matrix, requires the neutrino beams from a neutrino factory. The neutrino factory is a new concept for producing neutrino beams of unprecedented quality in terms of intensity, flavour composition, and precision of the beam parameters. Most importantly, the neutrino factory is the only known way to generate a high- intensity beam of electron neutrinos of high energy. The neutrino beam from a neutrino factory, in particular the electron-neutrino beam, enables the exploration of otherwise inaccessible domains in neutrino oscillation physics by exploiting baselines of planetary dimensions. Suitable detectors pose formidable challenges but seem within reach with only mode...

Solar neutrinos as a probe of dark matter-neutrino interactions

Energy Technology Data Exchange (ETDEWEB)

Capozzi, Francesco; Vecchi, Luca [Dipartimento di Fisica e Astronomia, Università di Padova, via Marzolo 8, I-35131 Padova (Italy); Shoemaker, Ian M., E-mail: capozzi.12@osu.edu, E-mail: ian.shoemaker@usd.edu, E-mail: vecchi@infn.pd.it [Department of Physics, University of South Dakota, Vermillion, SD 57069 (United States)

2017-07-01

Sterile neutrinos at the eV scale have long been studied in the context of anomalies in short baseline neutrino experiments. Their cosmology can be made compatible with our understanding of the early Universe provided the sterile neutrino sector enjoys a nontrivial dynamics with exotic interactions, possibly providing a link to the Dark Matter (DM) puzzle. Interactions between DM and neutrinos have also been proposed to address the long-standing 'missing satellites' problem in the field of large scale structure formation. Motivated by these considerations, in this paper we discuss realistic scenarios with light steriles coupled to DM . We point out that within this framework active neutrinos acquire an effective coupling to DM that manifests itself as a new matter potential in the propagation within a medium of asymmetric DM . Assuming that at least a small fraction of asymmetric DM has been captured by the Sun, we show that a sizable region of the parameter space of these scenarios can be probed by solar neutrino experiments, especially in the regime of small couplings and light mediators where all other probes become inefficient. In the latter regime these scenarios behave as familiar 3+1 models in all channels except for solar data, where a Solar Dark MSW effect takes place. Solar Dark MSW is characterized by modifications of the most energetic {sup 8}B and CNO neutrinos, whereas the other fluxes remain largely unaffected.

Medidas da condutividade térmica efetiva de modelos de polpas de frutas no estado congelado

Directory of Open Access Journals (Sweden)

Resende Jaime Vilela de

2002-01-01

Full Text Available As propriedades termofísicas de alimentos, necessárias nas simulações e cálculos do processo de congelamento, incluem principalmente a densidade, condutividade térmica e calor específico. Neste trabalho, as difusividades e condutividades térmicas da solução, usadas como modelo para o congelamento de polpas de frutas, foram medidas pelo método da sonda com aquecimento. Os experimentos foram conduzidos na faixa de -25 a 0masculineC com modelos alimentícios constituídos de 0,5% de K- carrageenan + 10% de sacarose (massa/volume de água. Modelos estruturais foram usados para as avaliações da condução de calor, combinada com a fração de gelo predita para as amostras a partir dos modelos de Heldman e foram comparados com os valores das condutividades térmicas efetivas medidas. Os modelos estruturais empregados foram: em série, paralelo e Maxwell-Eucken, com o gelo considerado como a fase dispersa. Em todos os ensaios, o modelo de Maxwell-Eucken apresentou os melhores resultados (erro máximo de 6,13% quando comparado com os valores experimentais medidos e foi escolhido para a predição da condutividade térmica efetiva de soluções-modelo de polpas de frutas congeladas. Os valores calculados da condutividade térmica foram ajustados em termos de funções polinomiais, divididas em quatro faixas de temperatura e podem ser usadas na resolução dos problemas de transferência de calor, nos processos de congelamento.

Minimalistic Neutrino Mass Model

CERN Document Server

De Gouvêa, A; Gouvea, Andre de

2001-01-01

We consider the simplest model which solves the solar and atmospheric neutrino puzzles, in the sense that it contains the smallest amount of beyond the Standard Model ingredients. The solar neutrino data is accounted for by Planck-mass effects while the atmospheric neutrino anomaly is due to the existence of a single right-handed neutrino at an intermediate mass scale between 10^9 GeV and 10^14 GeV. Even though the neutrino mixing angles are not exactly predicted, they can be naturally large, which agrees well with the current experimental situation. Furthermore, the amount of lepton asymmetry produced in the early universe by the decay of the right-handed neutrino is very predictive and may be enough to explain the current baryon-to-photon ratio if the right-handed neutrinos are produced out of thermal equilibrium. One definitive test for the model is the search for anomalous seasonal effects at Borexino.

Pathlength distributions of atmospheric neutrinos

Energy Technology Data Exchange (ETDEWEB)

Gaisser, T.K.; Stanev, Todor

1999-01-01

We discuss the distribution of the production heights of atmospheric neutrinos as a function of zenith angle and neutrino energy. The distributions can be used as the input for evaluation of neutrino propagation under various hypotheses for neutrino flavor oscillations. Their use may alter substantially the estimates of the oscillation parameters for almost horizontal atmospheric neutrinos.

NEUTRINO mass textures and the nature of new physics implied by present neutrino data

International Nuclear Information System (INIS)

Mohapatra, R.N.

1997-01-01

If all the indications for neutrino oscillations observed in the solar, atmospheric neutrino data as well as in the LSND experiment are borned out by the ongoing and future experiments, then they severely constrain the neutrino mass texture. In particular, the need for an extra ultra-light sterile neutrino species is hard to avoid. Such an extra neutrino has profound implication not only for physics beyond the standard model but even perhaps for physics beyond conventional grand unification. A scenario involving a parallel (or shadow) universe that interacts with the familiar universe only via the gravitational interactions where the ultra-lightness of the sterile neutrino follows from the same physics that explains the near masslessness of the familiar neutrinos is discussed in the presentation

Nutrición y Dietética como optativa para 4º de la ESO como medida de concienciación del alumnado sobre hábitos saludables, salud y obesidad

OpenAIRE

Delgado, Laura

2012-01-01

Este proyecto presenta la programación de una asignatura con la intención de suscitar interés y mejorar los conocimientos del alumnado en temas relacionados con la alimentación, la nutrición y la dietética y concienciarse de la situación actual de obesidad existente en su entorno, tomar medidas fundamentales en cuanto a hábitos sanos y saludables, tanto de alimentación como de ejercicio físico, para así poder frenar esta enfermedad tan grave, que cada vez afecta más a los jóven...

Evaluación del desarrollo testicular y medidas morfométricas en ovinos de pelo colombiano

Directory of Open Access Journals (Sweden)

Amado Espitia-Pacheco

2018-01-01

Full Text Available Las medidas corporales en ovinos son útiles como indicador de tipo y función, permiten mejorar la selección. Se conocen estudios biométricos en ovinos que, relacionan la importancia de estas medidas con algunas variables productivas. El objetivo del presente estudio fue evaluar el desarrollo testicular y su relación con los parámetros morfométricos en ovinos de pelo colombiano, en el municipio de Sampués, Sucre, Colombia. Se utilizaron doce ovinos machos (destetados nacidos entre febrero y abril del 2014, sobre los cuales se tomaron las siguientes medidas: circunferencia escrotal (CE, peso corporal (PC, altura a la grupa (AG, alzada a la cruz (AC y longitud testicular derecha e izquierda (LTD y LTI, cada veintiocho días hasta los doce meses de edad. Para CE se efectuó análisis de regresión múltiple (RM del PC; AG; AC; LT. Para describir la variación del LT, el modelo incluyó solo las variables PC; AG; AC. El grado de asociación entre las variables estudiadas, se realizó por medio de correlación Pearson. La circunferencia escrotal mostró una correlación alta con los parámetros morfométricos evaluados. Dentro del análisis de RM, el PC influyó en la variable CE (p<0,05, mientras que las demás variables no influyeron significativamente. Según el coeficiente de regresión asociado a la medición, por cada kg de incremento en PC, hubo un correspondiente aumento de 0,09 cm en la CE.

Neutrino cosmology

CERN Document Server

Lesgourgues, Julien; Miele, Gennaro; Pastor, Sergio

2013-01-01

The role that neutrinos have played in the evolution of the Universe is the focus of one of the most fascinating research areas that has stemmed from the interplay between cosmology, astrophysics and particle physics. In this self-contained book, the authors bring together all aspects of the role of neutrinos in cosmology, spanning from leptogenesis to primordial nucleosynthesis, their role in CMB and structure formation, to the problem of their direct detection. The book starts by guiding the reader through aspects of fundamental neutrino physics, such as the standard cosmological model and the statistical mechanics in the expanding Universe, before discussing the history of neutrinos in chronological order from the very early stages until today. This timely book will interest graduate students and researchers in astrophysics, cosmology and particle physics, who work with either a theoretical or experimental focus.

Supernova neutrinos

International Nuclear Information System (INIS)

John Beacom

2003-01-01

We propose that neutrino-proton elastic scattering, ν + p → ν + p, can be used for the detection of supernova neutrinos. Though the proton recoil kinetic energy spectrum is soft, with T p ≅ 2E ν 2 /M p , and the scintillation light output from slow, heavily ionizing protons is quenched, the yield above a realistic threshold is nearly as large as that from (bar ν) e + p → e + + n. In addition, the measured proton spectrum is related to the incident neutrino spectrum, which solves a long-standing problem of how to separately measure the total energy release and temperature of ν μ , ν τ , (bar ν) μ , and (bar ν) τ . The ability to detect this signal would give detectors like KamLAND and Borexino a crucial and unique role in the quest to detect supernova neutrinos

Neutrino Factory: status and prospects

International Nuclear Information System (INIS)

Long, K.

2011-01-01

The properties of the neutrino provide a unique window on physics beyond that described by the Standard Model. The study of sub-leading effects in neutrino oscillations has begun with the race to measure θ 13 consensus is emerging within the international community that a novel neutrino source is required to allow sensitive searches for leptonic CP violation to be carried out and the neutrino mass-hierarchy to be determined. The Neutrino Factory, in which intense neutrino beams are produced from the decay of muons, has been shown to out-perform the other proposed facilities. The physics case for the Neutrino Factory will be reviewed and the baseline design of the facility being developed by the International Design Study for the Neutrino Factory (the IDS-NF) collaboration will be described.

Steps towards the Neutrino Factory

International Nuclear Information System (INIS)

Long, K.

2012-01-01

The properties of the neutrino provide a unique window on physics beyond that described by the Standard Model. The study of sub-leading effects in neutrino oscillations has begun with the race to measure θ 13 . A consensus is emerging within the international community that a novel neutrino source is required to allow sensitive searches for leptonic CP violation to be carried out and the neutrino mass-hierarchy to be determined. The Neutrino Factory, in which intense neutrino beams are produced from the decay of muons, has been shown to out-perform the other proposed facilities. The physics case for the Neutrino Factory will be reviewed and the baseline design of the facility being developed by the International Design Study for the Neutrino Factory (the IDS-NF) collaboration will be described.

Neutrino masses and mixings

International Nuclear Information System (INIS)

Wolfenstein, L.

1991-01-01

Theoretical prejudices, cosmology, and neutrino oscillation experiments all suggest neutrino mass are far below present direct experimental limits. Four interesting scenarios and their implications are discussed: (1) a 17 keV ν τ , (2) a 30 ev ν τ making up the dark matter, (3) a 10 -3 ev ν μ to solve the solar neutrino problem, and (4) a three-neutrino MSW solution

Calculation of low-energy reactor neutrino spectra reactor for reactor neutrino experiments

Energy Technology Data Exchange (ETDEWEB)

Riyana, Eka Sapta; Suda, Shoya; Ishibashi, Kenji; Matsuura, Hideaki [Dept. of Applied Quantum Physics and Nuclear Engineering, Kyushu University, Kyushu (Japan); Katakura, Junichi [Dept. of Nuclear System Safety Engineering, Nagaoka University of Technology, Nagaoka (Japan)

2016-06-15

Nuclear reactors produce a great number of antielectron neutrinos mainly from beta-decay chains of fission products. Such neutrinos have energies mostly in MeV range. We are interested in neutrinos in a region of keV, since they may take part in special weak interactions. We calculate reactor antineutrino spectra especially in the low energy region. In this work we present neutrino spectrum from a typical pressurized water reactor (PWR) reactor core. To calculate neutrino spectra, we need information about all generated nuclides that emit neutrinos. They are mainly fission fragments, reaction products and trans-uranium nuclides that undergo negative beta decay. Information in relation to trans-uranium nuclide compositions and its evolution in time (burn-up process) were provided by a reactor code MVP-BURN. We used typical PWR parameter input for MVP-BURN code and assumed the reactor to be operated continuously for 1 year (12 months) in a steady thermal power (3.4 GWth). The PWR has three fuel compositions of 2.0, 3.5 and 4.1 wt% {sup 235}U contents. For preliminary calculation we adopted a standard burn-up chain model provided by MVP-BURN. The chain model treated 21 heavy nuclides and 50 fission products. The MVB-BURN code utilized JENDL 3.3 as nuclear data library. We confirm that the antielectron neutrino flux in the low energy region increases with burn-up of nuclear fuel. The antielectron-neutrino spectrum in low energy region is influenced by beta emitter nuclides with low Q value in beta decay (e.g. {sup 241}Pu) which is influenced by burp-up level: Low energy antielectron-neutrino spectra or emission rates increase when beta emitters with low Q value in beta decay accumulate. Our result shows the flux of low energy reactor neutrinos increases with burn-up of nuclear fuel.

Properties of neutrinos: Recent results

International Nuclear Information System (INIS)

Robertson, R.G.H.

1987-01-01

Recent progress in experimental determinations of the properties of neutrinos is summarized. In particular, the extensive work on direct kinematic measurements of neutrino mass, on neutrino counting and on neutrino oscillations is highlighted. It is concluded that there may already be sufficient information to fix the masses of the neutrinos, but the evidence is still far from convincing. 63 refs., 13 figs

Neutrino magnetic moment contribution to the neutrino-deuteron reaction

International Nuclear Information System (INIS)

Tsuji, K.; Nakamura, S.; Sato, T.; Kubodera, K.; Myhrer, F.

2004-01-01

We study the effect of the neutrino magnetic moment on the neutrino-deuteron breakup reaction, using a method called the standard nuclear physics approach, which has already been well tested for several electroweak processes involving the deuteron

Neutrino conversion in a neutrino flux: towards an effective theory of collective oscillations

Science.gov (United States)

Hansen, Rasmus S. L.; Smirnov, Alexei Yu.

2018-04-01

Collective oscillations of supernova neutrinos above the neutrino sphere can be completely described by the propagation of individual neutrinos in external potentials and are in this sense a linear phenomenon. An effective theory of collective oscillations can be developed based on certain assumptions about time dependence of these potentials. General conditions for strong flavor transformations are formulated and these transformations can be interpreted as parametric resonance effects induced by periodic modulations of the potentials. We study a simplified and solvable example, where a probe neutrino is propagating in a flux of collinear neutrinos, such that ν ν‑ interactions in the flux are absent. Still, this example retains the main feature—the coherent flavor exchange. Properties of the parametric resonance are studied, and it is shown that integrations over energies and emission points of the flux neutrinos suppress modulations of the potentials and therefore strong transformations. The transformations are also suppressed by changes in densities of background neutrinos and electrons.

Workshop on low energy neutrino physics

International Nuclear Information System (INIS)

2009-01-01

The main topics of the workshop are: the determination of the neutrino mixing angle theta-13, the experiments concerning the monitoring of reactors based on the measurement of neutrino spectra, solar neutrinos, supernovae neutrinos, geo-neutrinos, neutrino properties, neutrinoless double beta decay and future low energy neutrino detectors. This document gathers together the program of the workshop, the slides of the presentations, some abstracts and some posters

CERN: Neutrino facelift

Energy Technology Data Exchange (ETDEWEB)

Anon.

1991-11-15

With the termination this summer of the CHARM II neutrino experiment at the SPS proton synchrotron, CERN's 30- year tradition of neutrino physics came to a temporary halt. However with these enigmatic particles playing a vital role in today's Standard Model but continually reluctant to give up all their secrets, neutrino physics will continue to be in the forefront of this research.

GRAN SASSO/GRENOBLE: Artificial neutrino source confirms solar neutrino result

International Nuclear Information System (INIS)

Anon.

1995-01-01

In 1992, the Gallex experiment announced the first observation of the neutrinos produced in the primary proton-proton fusion reaction in the core of the Sun, reaction at the origin of the energy production by our star (September 1992, page 1). The Gallex team stressed that the observed neutrino flux was only about two-thirds of the predicted level, confirming the deficit observed by the two pioneering experiments, Ray Davis' chlorine-based detector in the USA and the Kamiokande study in Japan (which are only sensitive to neutrinos from subsidiary solar fusion processes). This deficit demands explanation, and could considerably modify our understanding of how stars shine and/or of neutrino physics. But before drawing conclusions, the Gallex result had to be checked. Gallex, installed in the Italian Gran Sasso underground Laboratory, is a radiochemical experiment using neutrino interactions to transform gallium-71 into germanium-71. The latter is radioactive and decays with a half-life of 11.4 days. Counting the germanium-71 atoms extracted from the target tank measures the neutrino flux to which the detector is exposed. Neutrinos are famous for their reluctance to interact. 65 billion per square centimetre per second on the surface of the Earth produce only one germanium-71 atom in the Gallex target containing 30 tons of gallium. This is at the limit of homeopathy (extracting few atoms of germanium-71 from a solution containing 10 30 atoms) and needs careful checking. Since it is not possible to switch off the Sun, the only recourse was to build an artificial neutrino source more powerful than the Sun as a benchmark. This was done last summer. Last May, 36 kilograms of chromium grains were placed in the Siloe reactor of the French Commissariat à l'énergie atomique, Grenoble. The chromium had been previously enriched to 40% chromium-50 by the Kurchatov Institute in Moscow (natural chromium contains only 4.5% chromium-50). A dedicated core was built for

Neutrino Oscillation Experiment at JHF

CERN Multimedia

2002-01-01

T2K is a long baseline neutrino experiment designed to investigate how neutrinos change from one flavor to another as they travel (neutrino oscillations). An intense beam of muon neutrinos is generated at the J-PARC nuclear physics site on the East coast of Japan and directed across the country to the Super-Kamiokande neutrino detector in the mountains of western Japan. The beam is measured once before it leaves the J-PARC site, using the near detector ND280, and again at Super-K, 295 km away: the change in the measured intensity and composition of the beam is used to provide information on the properties of neutrinos. The high intensity neutrino beam is produced in an off-axis configuration. The peak neutrino energy is tuned to the oscillation maximum of ∼ 0.6 GeV to maximize the sensitivity to neutrino oscillations. The science goals of T2K can be summarized as follows: •\tsearch for CP violation in the neutrino sector •\tdiscovery of νμ → νe ( i.e. the confirmation that θ13 > 0 ) •\tprecision ...

New phenomena in neutrino physics

International Nuclear Information System (INIS)

Kopp, Joachim

2009-01-01

In this thesis, we discuss two new concepts in neutrino physics: The neutrino Moessbauer effect and non-standard neutrino interactions. We show that neutrinos emitted and absorbed in recoil-free processes (Moessbauer neutrinos) can oscillate in spite of their near monochromaticity. We support this statement by quantum mechanical wave packet arguments and by a quantum field theoretical (QFT) calculation of the combined rate of Moessbauer neutrino emission, propagation and absorption. The QFT approach does not require any a priori assumptions on the neutrino wave function, and it allows us to include a realistic treatment of the different mechanisms leading to broadening of the emission and absorption lines. In the second part of this work, we study the phenomenology of non-standard neutrino interactions (NSI). We classifying the allowed NSI operators according to their impact on future oscillation experiments and present numerical results for the NSI sensitivities of reactor, superbeam and neutrino factory experiments. We point out that NSI could mimic standard oscillation effects, and might therefore lead to incorrect fit values for the oscillation parameters. For the case of the neutrino factory, we perform a detailed optimisation study to determine the optimum muon energy and detector configuration. (orig.)

New phenomena in neutrino physics

Energy Technology Data Exchange (ETDEWEB)

Kopp, Joachim

2009-04-15

In this thesis, we discuss two new concepts in neutrino physics: The neutrino Moessbauer effect and non-standard neutrino interactions. We show that neutrinos emitted and absorbed in recoil-free processes (Moessbauer neutrinos) can oscillate in spite of their near monochromaticity. We support this statement by quantum mechanical wave packet arguments and by a quantum field theoretical (QFT) calculation of the combined rate of Moessbauer neutrino emission, propagation and absorption. The QFT approach does not require any a priori assumptions on the neutrino wave function, and it allows us to include a realistic treatment of the different mechanisms leading to broadening of the emission and absorption lines. In the second part of this work, we study the phenomenology of non-standard neutrino interactions (NSI). We classifying the allowed NSI operators according to their impact on future oscillation experiments and present numerical results for the NSI sensitivities of reactor, superbeam and neutrino factory experiments. We point out that NSI could mimic standard oscillation effects, and might therefore lead to incorrect fit values for the oscillation parameters. For the case of the neutrino factory, we perform a detailed optimisation study to determine the optimum muon energy and detector configuration. (orig.)

Detection of supernova neutrinos by neutrino-proton elastic scattering

International Nuclear Information System (INIS)

Beacom, John F.; Farr, Will M.; Vogel, Petr

2002-01-01

We propose that neutrino-proton elastic scattering, ν+p→ν+p, can be used for the detection of supernova neutrinos in scintillator detectors. Though the proton recoil kinetic energy spectrum is soft, with T p ≅2E ν 2 /M p , and the scintillation light output from slow, heavily ionizing protons is quenched, the yield above a realistic threshold is nearly as large as that from ν(bar sign) e +p→e + +n. In addition, the measured proton spectrum is related to the incident neutrino spectrum, which solves a long-standing problem of how to separately measure the total energy and temperature of ν μ , ν τ , ν(bar sign) μ , and ν(bar sign) τ . The ability to detect this signal would give detectors like KamLAND and Borexino a crucial and unique role in the quest to detect supernova neutrinos

Simulation of coherent nonlinear neutrino flavor transformation in the supernova environment: Correlated neutrino trajectories

Science.gov (United States)

Duan, Huaiyu; Fuller, George M.; Carlson, J.; Qian, Yong-Zhong

2006-11-01

We present results of large-scale numerical simulations of the evolution of neutrino and antineutrino flavors in the region above the late-time post-supernova-explosion proto-neutron star. Our calculations are the first to allow explicit flavor evolution histories on different neutrino trajectories and to self-consistently couple flavor development on these trajectories through forward scattering-induced quantum coupling. Employing the atmospheric-scale neutrino mass-squared difference (|δm2|≃3×10-3eV2) and values of θ13 allowed by current bounds, we find transformation of neutrino and antineutrino flavors over broad ranges of energy and luminosity in roughly the “bi-polar” collective mode. We find that this large-scale flavor conversion, largely driven by the flavor off-diagonal neutrino-neutrino forward scattering potential, sets in much closer to the proto-neutron star than simple estimates based on flavor-diagonal potentials and Mikheyev-Smirnov-Wolfenstein evolution would indicate. In turn, this suggests that models of r-process nucleosynthesis sited in the neutrino-driven wind could be affected substantially by active-active neutrino flavor mixing, even with the small measured neutrino mass-squared differences.

La ciudad ante el contagio: medidas políticas y administrativas dictadas en la epidemia de fiebre amarilla de 1804 en Alicante

Directory of Open Access Journals (Sweden)

Pascual Artiaga, Mercedes

2002-06-01

Full Text Available Since 1800 the yellow fever started producing epidemic incidents in the Iberian Peninsula. In this article the measures that were established by the different sanitary assemblies implied in the control of the epìdemic outbreak that affected the city of Alicante in 1804 are shown and analysed. The study of this case in Alicante has allowed to put in context this analysis in the framework of what happened in other places during this and other epidemies. It is proved the coexistence of traditional measures of prevention and of new ones. The political and sanitary speech focused on assuring the isolation of the population affected in order to avoid the spreading of this disease and to extend it as long as possible, as a quarantee for the surrounding cities.

el artículo se presentan y analizan las medidas que instauraron las diversas Juntas de Sanidad implicadas en el control del brote epidémico que afectó a la ciudad de Alicante en 1804. El estudio del caso alicantino ha permitido contextualizar dicho análisis en el marco de lo sucedido en otras localidades durante ésta y otras epidemias. Se constata la coexistencia de medidas tradicionales de prevención y de nuevas medidas. Las medidas administrativas y sanitarias se centraron en asegurar el aislamiento de la población afectada para evitar la extensión de la enfermedad y prolongarlo el mayor tiempo posible, como una garantía para las localidades vecinas.

An Experimentalist's Overview of Solar Neutrinos

Science.gov (United States)

Oser, Scott M.

2012-02-01

Four decades of solar neutrino research have demonstrated that solar models do a remarkable job of predicting the neutrino fluxes from the Sun, to the extent that solar neutrinos can now serve as a calibrated neutrino source for experiments to understand neutrino oscillations and mixing. In this review article I will highlight the most significant experimental results, with emphasis on the latest model-independent measurements from the Sudbury Neutrino Observatory. The solar neutrino fluxes are seen to be generally well-determined experimentally, with no indications of time variability, while future experiments will elucidate the lower energy part of the neutrino spectrum, especially pep and CNO neutrinos.

An Experimentalist's Overview of Solar Neutrinos

International Nuclear Information System (INIS)

Oser, Scott M

2012-01-01

Four decades of solar neutrino research have demonstrated that solar models do a remarkable job of predicting the neutrino fluxes from the Sun, to the extent that solar neutrinos can now serve as a calibrated neutrino source for experiments to understand neutrino oscillations and mixing. In this review article I will highlight the most significant experimental results, with emphasis on the latest model-independent measurements from the Sudbury Neutrino Observatory. The solar neutrino fluxes are seen to be generally well-determined experimentally, with no indications of time variability, while future experiments will elucidate the lower energy part of the neutrino spectrum, especially pep and CNO neutrinos.

Leptogenesis and neutrino masses

International Nuclear Information System (INIS)

Pluemacher, M.

2004-01-01

Thermal leptogenesis explains the baryon asymmetry of the universe by the out-of-equilibrium decays of heavy right-handed neutrinos. In the minimal seesaw model this leads to interesting implications for light neutrino properties. In particular, quasi-degenerate light neutrino masses are incompatible with leptogenesis. An upper bound on light neutrino masses of 0.1 eV can be derived, which will be tested by forthcoming laboratory experiments and cosmology. (author)

Status of Heavy Neutrino Experiments

CERN Document Server

Wynne, Benjamin; The ATLAS collaboration

2017-01-01

The observation of neutrino oscillations raises the possibility that there exist additional, undiscovered high-mass neutrinos, giving mass to Standard Model neutrinos via the seesaw mechanism. By pushing the collider energy frontier at the LHC, the possibility arises that these heavy neutrinos may be produced and identified. We summarise the latest LHC results of searches for heavy neutrinos in a variety of final states.

Solar neutrino spectrum, sterile neutrinos and additional radiation in the Universe

International Nuclear Information System (INIS)

Holanda, Pedro Cunha de

2011-01-01

Full text: Recent results from the SNO, Super-Kamiokande and Borexino experiments do not show the expected upturn of the energy spectrum of events (the ratio R ≡ N obs /N SSM ) at low energies. At the same time, cosmological observations testify for possible existence of additional relativistic degrees of freedom in the early Universe: ΔN eff = 1 - 2. These facts strengthen the case of very light sterile neutrino, ν s , with Δm 0 1 2 ∼ (0.7 - 2) . 10 -5 e V 2 , which mixes weakly with the active neutrinos. The ν s mixing in the mass eigenstate ν 1 characterized by sin 2 2∝ ∼ 10 -3 can explain an absence of the upturn. The mixing of ν s in the eigenstate ν 3 with sin 2 β ∼ 0.1 leads to production of ν s via oscillations in the Universe and to additional contribution Δ N eff ∼ 0.7 -1 before the big bang nucleosynthesis and later. Such a mixing can be tested in forthcoming experiments with the atmospheric neutrinos as well as in future accelerator long baseline experiments. It has substantial impact on conversion of the supernova neutrinos. We perform a qualitative and quantitative analysis of solar neutrino data including a fourth neutrino with different mixings with the active neutrino sector.(author)

Neutrino-oscillation search with cosmic-ray neutrinos

International Nuclear Information System (INIS)

Ayres, D.S.; Cortez, B.; Gaisser, T.K.; Mann, A.K.; Shrock, R.E.; Sulak, L.R.

1984-01-01

A sensitive search for neutrino oscillations involving ν/sub e/, ν/sub μ/, and ν/sub tau/ may be provided by measurements of the ratio of the total interaction rates of upward- and downward-going cosmic-ray neutrinos within a massive (approx.10 kton) detector. Assuming mixing between all pairs of ν/sub e/, ν/sub μ/, and ν/sub tau/, the experiment is capable of observing time-averaged probabilities /sub t/ and /sub t/ of magnitude set by mixing strengths corresponding to, e.g., the d- to s-quark mixing strength, and of reaching the limit Δm/sub i/j 2 equivalentVertical Barm/sub i/ 2 -m/sub j/ 2 Vertical Barroughly-equal10 -4 eV 2 , where m/sub i/, and m/sub j/ are neutrino mass eigenstates, and P/sub e/tau and P/sub mutau/ are the probabilities for ν/sub e/ and ν/sub μ/, respectively, to oscillate into ν/sub tau/ after traversing a distance Lroughly-equal diameter of the Earth. Possible ambiguities may be resolved through comparison of the ratios N/sub e//N/sub μ/ for the upward- and downward-going neutrinos

Chaotic amplification of neutrino chemical potentials by neutrino oscillations in big bang nucleosynthesis

International Nuclear Information System (INIS)

Shi, X.

1996-01-01

We investigate in detail the parameter space of active-sterile neutrino oscillations that amplifies neutrino chemical potentials at the epoch of big bang nucleosynthesis. We calculate the magnitude of the amplification and show evidence of chaos in the amplification process. We also discuss the implications of the neutrino chemical potential amplification in big bang nucleosynthesis. It is shown that with a ∼1 eV ν e , the amplification of its chemical potential by active-sterile neutrino oscillations can lower the effective number of neutrino species at big bang nucleosynthesis to significantly below three. copyright 1996 The American Physical Society

Chaotic amplification of neutrino chemical potentials by neutrino oscillations in big bang nucleosynthesis

Energy Technology Data Exchange (ETDEWEB)

Shi, X. [Department of Physics, Queen`s University, Kingston, Ontario, K7L 3N6 (CANADA)

1996-08-01

We investigate in detail the parameter space of active-sterile neutrino oscillations that amplifies neutrino chemical potentials at the epoch of big bang nucleosynthesis. We calculate the magnitude of the amplification and show evidence of chaos in the amplification process. We also discuss the implications of the neutrino chemical potential amplification in big bang nucleosynthesis. It is shown that with a {approximately}1 eV {nu}{sub {ital e}}, the amplification of its chemical potential by active-sterile neutrino oscillations can lower the effective number of neutrino species at big bang nucleosynthesis to significantly below three. {copyright} {ital 1996 The American Physical Society.}

New neutrino oscillation results from NOVA

CERN Multimedia

CERN. Geneva

2018-01-01

Neutrinos oscillate among flavors as they travel because a neutrino of a particular flavor is also a superposition of multiple neutrinos with slightly different masses.  The interferometric nature of oscillations allows these tiny mass differences to be measured, along with the parameters of the PMNS matrix which governs the mixing. However, since neutrinos only interact weakly, a powerful neutrino source and massive detectors are required to measure them. In this talk I will show recently updated results from NOvA, a long-baseline neutrino oscillation experiment at Fermilab with two functionally identical scintillator detectors. I will present measurements of muon neutrino disappearance and electron neutrino appearance, and what constraints those measurements put on the remaining open questions in neutrino oscillations: Is the neutrino mass hierarchy "normal" or "inverted?" Do neutrino oscillations violate CP symmetry? Is the mixing in the atmospheric sector maximal? The recent update includes 50%...

Supernova relic electron neutrinos and anti-neutrinos in future large-scale observatories

International Nuclear Information System (INIS)

Volpe, C.; Welzel, J.

2007-01-01

We investigate the signal from supernova relic neutrinos in future large scale observatories, such as MEMPHYS (UNO, Hyper-K), LENA and GLACIER, at present under study. We discuss that complementary information might be gained from the observation of supernova relic electron antineutrinos and neutrinos using the scattering on protons on one hand, and on nuclei such as oxygen, carbon or argon on the other hand. When determining the relic neutrino fluxes we also include, for the first time, the coupling of the neutrino magnetic moment to magnetic fields within the core collapse supernova. We present numerical results on both the relic ν e and ν-bar e fluxes and on the number of events for ν e + C 12 , ν e + O 16 , ν e + Ar 40 and ν-bar e + p for various oscillation scenarios. The observation of supernova relic neutrinos might provide us with unique information on core-collapse supernova explosions, on the star formation history and on neutrino properties, that still remain unknown. (authors)

16th International Workshop on Neutrino Factories and Future Neutrino Beam Facilities

CERN Document Server

2015-01-01

These proceedings present the written contributions from participants of the 16th International Workshop on Neutrino Factories and Future Neutrino Beam Facilities (NUFACT 2014) that was held at the University of Glasgow (Glasgow, Scotland, United Kingdom) from 25-30 August 2014. This edition of the NUFACT annual meetings, which started in 1999, consisted of 24 plenary and 92 parallel talks and various poster sessions, with the participation of 124 delegates. Furthermore, the International Neutrino Summer School 2014 was held from 10-22 August 2014 at St Andrews, Scotland, in the two weeks before NUFACT 2014. It was intended for young scientists with an interest in neutrino physics in such a way that they would be able to participate and contribute to the NUFACT workshop as well. The objectives of the NUFACT workshops are to review progress on different studies for future accelerator-based neutrino oscillation facilities, with the goal to discover the mass hierarchy of neutrinos, CP violation in the leptonic s...

Textos padronizados em português (BR para medida da velocidade de leitura: comparação com quatro idiomas europeus New standardized texts in Brazilian Portuguese to assess reading speed: comparison with four European languages

Directory of Open Access Journals (Sweden)

André Messias

2008-08-01

Full Text Available OBJETIVO: Desenvolver textos para medida da velocidade de leitura comparáveis com outros quatro idiomas europeus. MÉTODOS: Dez textos com similar grau de dificuldade, número de caracteres, número de palavras e sintaxe (segundo a teoria de Gibson foram desenvolvidos por um especialista em lingüística, em português (BR, fazendo-se a tradução de textos previamente padronizados em quatro idiomas: inglês, francês, finlandês e alemão. A velocidade de leitura foi medida em 25 indivíduos saudáveis de idade entre 19 e 35 anos (mediana=24 anos com os dez textos. RESULTADOS: A velocidade de leitura nos textos em português foi em média 1100 ± 167 (desvio padrão caracteres por minuto. Pequenas diferenças foram encontradas entre as velocidades de leitura medidas com os dez textos, e essas diferenças não foram estatisticamente significantes em grupos de no mínimo seis textos. A velocidade de leitura dos voluntários da mesma faixa etária nos outros idiomas foi: alemão: 1126 ± 105; finlandês: 1263 ± 142; francês: 1214 ± 152 e inglês: 1234 ± 147. CONCLUSÃO: Os autores desenvolveram um conjunto de textos em português (BR padronizados e homogêneos para medida da velocidade de leitura, que são comparáveis com textos em outros quatro idiomas europeus. Esses textos podem ser usados para estudos multicêntricos internacionais envolvendo leitura e visão subnormal.PURPOSE: To develop standardized texts in Brazilian Portuguese to assess reading speed and compare performances among four European languages. METHODS: 10 texts were designed by a linguistic expert at the level of a sixth grade reading material (reading ages 10-12 years and were matched for length and syntactic complexity, according to the syntactic prediction locality theory of Gibson. Normally sighted native speaking volunteers aged 18-35 years read each text aloud at random. RESULTS: The reading speed was on average 1100 ± 167 (standard deviation characters per minute

Neutrinos in astrophysics

CERN Document Server

Rees, Martin J

1980-01-01

The amount of 4He synthesised in the "big bang" is sensitive to the early particle content and to the expansion rate. If there was indeed a "big bang", surprisingly strong conclusions can be drawn about the number of species of neutrinos, and about the possibility that such particles have non-zero rest mass. The dynamics of supernovae are sensitive to the det~ils of neutrino physics; such explosions would yield IO L-1053 ergs of -v IO Mev neutrinos, in a burst lasting a few milliseconds. Galactic nuclei, cosmic ray sources and other high energy cosmic phenomena could yield a low background of~ 10 Gev neutrinos.

Neutrinos in supernovae

International Nuclear Information System (INIS)

Cooperstein, J.

1986-10-01

The role of neutrinos in Type II supernovae is discussed. An overall view of the neutrino luminosity as expected theoretically is presented. The different weak interactions involved are assessed from the standpoint of how they exchange energy, momentum, and lepton number. Particular attention is paid to entropy generation and the path to thermal and chemical equilibration, and to the phenomenon of trapping. Various methods used to calculate the neutrino flows are considered. These include trapping and leakage schemes, distribution-averaged transfer, and multi-energy group methods. The information obtained from the neutrinos caught from Supernova 1987a is briefly evaluated. 55 refs., 7 figs

A search for matter enhanced neutrino oscillations through measurements of day and night solar neutrino fluxes at the Sudbury Neutrino Observatory

Science.gov (United States)

Miknaitis, Kathryn Kelly Schaffer

The Sudbury Neutrino Observatory (SNO) is a heavy-water Cherenkov detector designed to study 8B neutrinos from the sun. Through the charged-current (CC) and neutral-current (NC) reactions of neutrinos on deuterium, SNO separately determines the flux of electron neutrinos and the flux of all active flavors of solar 8B neutrinos. SNO is also sensitive to the elastic scattering (ES) of neutrinos on electrons in the heavy water. Measurements of the CC and NC rates in SNO have conclusively demonstrated solar neutrino flavor change. This flavor change is believed to be caused by matter-enhanced oscillations in the sun, through the Mikheyev-Smirnov-Wolfenstein (MSW) effect. Matter effects could also change the flavor composition of neutrinos that traverse the earth. A comparison of the day and night measured CC flux at SNO directly tests for the MSW effect and contributes to constraints on neutrino oscillation parameters in the MSW model. We perform measurements of the day and night neutrino fluxes using data from the second phase of SNO, in which salt (NaCl) was added to the heavy water to enhance sensitivity to the NC reaction. Better discrimination between CC and NC events in the salt phase allows the fluxes to be determined without constraining the neutrino energy spectrum. The day-night asymmetry in the CC flux measured in this model-independent analysis is ACC = [-5.6 +/- 7.4(stat.) +/- 5.3(syst.)]%, where the asymmetry is defined as the difference between the night and day values divided by their average. The asymmetries in the NC and ES fluxes are ANC = [4.2 +/- 8.6(stat.) +/- 7.2(syst.)]%, and AES = (14.6 +/- 19.8(stat.) +/- 3.3(syst.)]%. The neutral current asymmetry is expected to be zero assuming standard neutrino oscillations. When we constrain it to be zero, we obtain ACC = [-3.7 +/- 6.3(stat.) +/- 3.2(syst.)]% and AES = [15.3 +/- 19.8(stat.) +/- 3.0(syst.)]%. The day and night energy spectra from the CC reaction have been measured and show no evidence for

The Sudbury neutrino observatory

International Nuclear Information System (INIS)

McLatchie, W.; Earle, E.D.

1987-08-01

This report initially discusses the Homestake Mine Experiment, South Dakota, U.S.A. which has been detecting neutrinos in 38 x 10 litre vats of cleaning fluid containing chlorine since the 1960's. The interation between neutrinos and chlorine produces argon so the number of neutrinos over time can be calculated. However, the number of neutrinos which have been detected represent only one third to one quarter of the expected number i.e. 11 per month rather than 48. It is postulated that the electron-neutrinos originating in the solar core could change into muon- or tau-neutrinos during passage through the high electron densities of the sun. The 'low' results at Homestake could thus be explained by the fact that the experiment is only sensitive to electron-neutrinos. The construction of a heavy water detector is therefore proposed as it would be able to determine the energy of the neutrinos, their time of arrival at the detector and their direction. It is proposed to build the detector at Creighton mine near Sudbury at a depth of 6800 feet below ground level thus shielding the detector from cosmic rays which would completely obscure the neutrino signals from the detector. The report then discusses the facility itself, the budget estimate and the social and economic impact on the surrounding area. At the time of publication the proposal for the Sudbury Neutrino Observatory was due to be submitted for peer review by Oct. 1, 1987 and then to various granting bodies charged with the funding of scientific research in Canada, the U.S.A. and Britain

Sterile Neutrino Search with MINOS

International Nuclear Information System (INIS)

Devan, Alena V.

2015-01-01

MINOS, Main Injector Neutrino Oscillation Search, is a long-baseline neutrino oscillation experiment in the NuMI muon neutrino beam at the Fermi National Accelerator Laboratory in Batavia, IL. It consists of two detectors, a near detector positioned 1 km from the source of the beam and a far detector 734 km away in Minnesota. MINOS is primarily designed to observe muon neutrino disappearance resulting from three flavor oscillations. The Standard Model of Particle Physics predicts that neutrinos oscillate between three active flavors as they propagate through space. This means that a muon-type neutrino has a certain probability to later interact as a different type of neutrino. In the standard picture, the neutrino oscillation probabilities depend only on three neutrino flavors and two mass splittings, Δm 2 . An anomaly was observed by the LSND and MiniBooNE experiments that suggests the existence of a fourth, sterile neutrino flavor that does not interact through any of the known Standard Model interactions. Oscillations into a theoretical sterile flavor may be observed by a deficit in neutral current interactions in the MINOS detectors. A distortion in the charged current energy spectrum might also be visible if oscillations into the sterile flavor are driven by a large mass-squared difference, Δm s 2 ~ 1 eV 2 . The results of the 2013 sterile neutrino search are presented here.

CERN: Neutrino facelift

International Nuclear Information System (INIS)

Anon.

1991-01-01

With the termination this summer of the CHARM II neutrino experiment at the SPS proton synchrotron, CERN's 30- year tradition of neutrino physics came to a temporary halt. However with these enigmatic particles playing a vital role in today's Standard Model but continually reluctant to give up all their secrets, neutrino physics will continue to be in the forefront of this research

Study of different type neutrino oscillations based on neutrino beams from 600 GeV

International Nuclear Information System (INIS)

Aref'ev, A.S.

1994-01-01

The problems of the different type neutrino oscillations based on a wide-band and narrow-band neutrino beam from the 600 GeV UNK-1 machine using the Baical Neutrino Telescope (4200 km from a accelerator) are discussed. The main parameters of the neutrino channel are presented. 17 refs.; 12 figs.; 1 tab

A Measurement of Neutrino Charged Current Interactions and a Search for Muon Neutrino Disappearance with the Fermilab Booster Neutrino Beam

Energy Technology Data Exchange (ETDEWEB)

Nakajima, Yasuhiro [Kyoto Univ. (Japan)

2011-01-01

In this thesis, we report on a measurement of muon neutrino inclusive charged current interactions on carbon in the few GeV region, using the Fermilab Booster Neutrino Beam. The all neutrino mode data collected in the SciBooNE experiment is used for this analysis. We collected high-statistics CC interaction sample at SciBooNE, and extracted energy dependent inclusive charged current interaction rates and cross sections for a wide energy range from 0.25 GeV to ~3 GeV. We measure the interaction rates with 6-15% precision, and the cross sections with 10-30% precision. We also made an energy integrated measurements, with the precisions of 3% for the rate, and 8% for the cross section measurements. This is the first measurement of the CC inclusive cross section on carbon around 1 GeV. This inclusive interaction measurement is nearly free from effects of hadron re-interactions in the nucleus. Hence, it is complementary to other exclusive cross section measurements, and essential to understand the neutrino interaction cross sections in the few GeV region, which is relevant to ongoing and future neutrino oscillation experiments. This analysis also provides the normalization for SciBooNE's previous cross section ratio measurements for charged current coherent pion production and neutral current neutral pion production. Then, a precise comparison between our previous measurements and the model predictions becomes possible. The result of the interaction rate measurement is used to constrain the product of the neutrino flux and the cross section at the other experiment on the Fermilab Booster Neutrino Beam: Mini-BooNE. We conducted a search for short-baseline muon neutrino disappearance using data both from SciBooNE and MiniBooNE, to test a possible neutrino oscillation with sterile neutrinos which is suggested by the LSND experiment. With this constraint by SciBooNE, we significantly reduced the flux and the cross section uncertainties at MiniBooNE, and achieved the

Hardron production and neutrino beams

Science.gov (United States)

Guglielmi, A.

2006-11-01

The precise measurements of the neutrino mixing parameters in the oscillation experiments at accelerators require new high-intensity and high-purity neutrino beams. Ancillary hadron-production measurements are then needed as inputs to precise calculation of neutrino beams and of atmospheric neutrino fluxes.

First all-flavor neutrino pointlike source search with the ANTARES neutrino telescope

NARCIS (Netherlands)

Albert, A.; André, M.; Anghinolfi, M.; Anton, G.; Ardid, M.; Aubert, J.-J.; Avgitas, T.; Baret, B.; Barrios-Martí, J.; Basa, S.; Belhorma, B.; Bertin, V.; Biagi, S.; Bormuth, R.; Bourret, S.; Bouwhuis, M.C.; Brânzas, H.; Bruijn, R.; Brunner, J.; Busto, J.; Capone, A.; Caramete, L.; Carr, J.; Celli, S.; Cherkaoui El Moursli, R.; Chiarusi, T.; Circella, M.; Coelho, J.A.B.; Coleiro, A.; Coniglione, R.; Costantini, H.; Coyle, P.; Creusot, A.; Díaz, A.F.; Deschamps, A.; De Bonis, G.; Distefano, C.; Di Palma, I.; Domi, A.; Donzaud, C.; Dornic, D.; Drouhin, D.; Eberl, T.; El Bojaddaini, I.; El Khayati, N.; Elsässer, D.; Enzenhöfer, A.; Ettahiri, A.; Fassi, F.; Felis, I.; Fusco, L.A.; Galatà, S.; Gay, P.; Giordano, V.; Glotin, H.; Grégoire, T.; Gracia-Ruiz, R.; Graf, K.; Hallmann, S.; van Haren, H.; Heijboer, A.J.; Hello, Y.; Hernández-Rey, J.J.; Hößl, J.; Hofestädt, J.; Hugon, C.; Illuminati, G.; James, C.W.; de Jong, M.; Jongen, M.; Kadler, M.; Kalekin, O.; Katz, U.; Kießling, D.; Kouchner, A.; Kreter, M.; Kreykenbohm, I.; Kulikovskiy, V.; Lachaud, C.; Lahmann, R.; Lefèvre, D.; Leonora, E.; Lotze, M.; Loucatos, S.; Marcelin, M.; Margiotta, A.; Marinelli, A.; Martinez-Mora, J.A.; Mele, R.; Melis, K.; Michael, T.; Migliozzi, P.; Moussa, A.; Navas, S.; Nezri, E.; Organokov, M.; Pavalas, G.E.; Pellegrino, C.; Perrina, C.; Piattelli, P.; Popa, V.; Pradier, T.; Quinn, L.; Racca, C.; Riccobene, G.; Sánchez-Losa, A.; Saldaña, M.; Salvadori, I.; Samtleben, D.F.E.; Sanguineti, M.; Sapienza, P.; Schüssler, F.; Sieger, C.; Spurio, M.; Stolarczyk, T.; Taiuti, M.; Tayalati, Y.; Trovato, A.; Turpin, D.; Tönnis, C.; Vallage, B.; Van Elewyck, V.; Versari, F.; Vivolo, D.; Vizzoca, A.; Wilms, J.; Zornoza, J.D.; Zúñiga, J.

2017-01-01

A search for cosmic neutrino sources using the data collected with the ANTARES neutrino telescope between early 2007 and the end of 2015 is performed. For the first time, all neutrino interactions --charged and neutral current interactions of all flavours-- are considered in a search for point-like

Experimental studies of neutrino oscillations

CERN Document Server

Kajita, Takaaki

2016-01-01

The 2015 Nobel Prize in physics has been awarded to Takaaki Kajita and Arthur McDonald "for the discovery of neutrino oscillations, which shows that neutrinos have mass". Takaaki Kajita of Tokyo University is a Japanese physicist, known for neutrino experiments at the Kamiokande and its successor, Super-Kamiokande. This volume of collected works of Kajita on neutrino oscillations provides a good glimpse into as well as a record of the rise and the role of Asian research in the frontiers of neutrino physics. Japan is now a major force in the study of the 3 families of neutrinos. Much remains to be done to clarify the Dirac vs. Majorana nature of the neutrino, and the cosmological implications of the neutrino. The collected works of Kajita and his Super-Kamiokande group will leave an indelible foot-print in the history of big and better science.

Again on neutrino oscillations

International Nuclear Information System (INIS)

Bilenky, S.M.; Pontecorvo, B.

1976-01-01

The general case is treated of a weak interaction theory in which a term violating lepton charges is present. In such a scheme the particles with definite masses are Majorana neutrinos (2N if in the weak interaction participate N four-component neutrinos). Neutrino oscillations are discussed and it is shown that the minimum average intensity at the earth of solar neutrinos is 1/2N of the intensity expected when oscillations are absent

Neutrino confinement in collapsing stellar cores

International Nuclear Information System (INIS)

Chung, K.C.

1987-01-01

Neutrino confinement is expected to occur in the core of highly evolved stars, leading to the formation of a degenerate neutrino gas. The main neutrino sources are briefly reviewed and the neutrino processes relevant to the neutrino opacity in the stellar matter are discussed. Implications for the equation of state of neutrino-trapped matter are examined. (author) [pt

Solar neutrinos

International Nuclear Information System (INIS)

Schatzman, E.

1983-01-01

The solar energy is produced by a series of nuclear reactions taking place in the deep interior of the sun. Some of these reactions produce neutrinos which may be detected, the proper detection system being available. The results of the Davis experiment (with 37 Cl) are given, showing a deficiency in the solar neutrino flux. The relevant explanation is either a property of the neutrino or an important change in the physics of the solar models. The prospect of a new experiment (with 71 Ga) is important as it will decide which of the two explanations is correct [fr

Solar neutrinos and gravity

International Nuclear Information System (INIS)

Kuo, T.K.

2001-01-01

We review the possibility that the solar neutrino problem can be explained by neutrinos violating the equivalence principle. It is found that such a scenario can be ruled out when one takes into account data from high energy accelerator neutrino experiments

Neutrino mixing and big bang nucleosynthesis

Science.gov (United States)

Bell, Nicole

2003-04-01

We analyse active-active neutrino mixing in the early universe and show that transformation of neutrino-antineutrino asymmetries between flavours is unavoidable when neutrino mixing angles are large. This process is a standard Mikheyev-Smirnov-Wolfenstein flavour transformation, modified by the synchronisation of momentum states which results from neutrino-neutrino forward scattering. The new constraints placed on neutrino asymmetries eliminate the possibility of degenerate big bang nucleosynthesis.Implications of active-sterile neutrino mixing will also be reviewed.

Neutrino mass hierarchy determination via atmospheric neutrinos with future detectors

International Nuclear Information System (INIS)

Gandhi, Raj; Ghoshal, Pomita; Goswami, Srubabati; Mehta, Poonam; Sankar, S Uma; Shalgar, Shashank

2008-01-01

The issue of determining the neutrino mass hierarchy is one of the outstanding questions in neutrino physics. We consider the potential of hierarchy determination using atmospheric neutrinos as the source in three different proposed future detectors: A large Iron Calorimeter detector, a megaton Water Cerenkov detector and a large-mass Liquid Argon detector. If the mixing angle θ 13 is about 10 deg. (close to CHOOZ upper bound), the hierarchy sensitivity is essentially determined by resonant matter effects. To maximize the potential of these effects in atmospheric neutrinos, charge discrimination capability in the detector is desirable. Hence, detectors with this capability have an advantage in hierarchy determination. We compare and contrast the performance of the above three detectors in this respect. We perform a realistic analysis of the above future detectors for atmospheric neutrinos and show that it is possible to achieve a significant hierarchy sensitivity if the detector characteristics are favourable. Note: The abstract has been modified from its original form to incorporate suggestions received during the conference. The poster is being submitted in its original form.

Sterile Neutrinos in Cold Climates

International Nuclear Information System (INIS)

Jones, Benjamin J.P.

2015-01-01

Measurements of neutrino oscillations at short baselines contain an intriguing set of experimental anomalies that may be suggestive of new physics such as the existence of sterile neutrinos. This three-part thesis presents research directed towards understanding these anomalies and searching for sterile neutrino oscillations. Part I contains a theoretical discussion of neutrino coherence properties. The open-quantum-system picture of neutrino beams, which allows a rigorous prediction of coherence distances for accelerator neutrinos, is presented. Validity of the standard treatment of active and sterile neutrino oscillations at short baselines is verified, and non-standard coherence loss effects at longer baselines are predicted. Part II concerns liquid argon detector development for the MicroBooNE experiment, which will search for short-baseline oscillations in the Booster Neutrino Beam at Fermilab. Topics include characterization and installation of the MicroBooNE optical system; test-stand measurements of liquid argon optical properties with dissolved impurities; optimization of wavelength-shifting coatings for liquid argon scintillation light detection; testing and deployment of high-voltage surge arrestors to protect TPC field cages; and software development for optical and TPC simulation and reconstruction. Part III presents a search for sterile neutrinos using the IceCube neutrino telescope, which has collected a large sample of atmospheric-neutrino-induced events in the 1-10 TeV energy range. Sterile neutrinos would modify the detected neutrino flux shape via MSW-resonant oscillations. Following a careful treatment of systematic uncertainties in the sample, no evidence for MSW-resonant oscillations is observed, and exclusion limits on 3+1 model parameter space are derived. Under the mixing assumptions made, the 90% confidence level exclusion limit extends to sin 2 2θ 24 ≤ 0.02 at m 2 ~ 0.3 eV 2 , and the LSND and MiniBooNE allowed regions are excluded at

Nonzero θ13 and neutrino masses from the modified tri-bi-maximal neutrino mixing matrix

International Nuclear Information System (INIS)

Damanik, A.

2014-01-01

There are 3 types of neutrino mixing matrices: tri-bi-maximal, bi-maximal and democratic. These 3 types of neutrino mixing matrices predict that the mixing angle θ 13 should be null. Motivated by the recent experimental evidence of nonzero and relatively large θ 13 , we modified the tribimaximal mixing matrix by introducing a simple perturbation matrix into tribimaximal neutrino mixing matrix. In this scenario, we obtained nonzero mixing angle θ 13 =7.9 degrees which is in agreement with the present experimental results. By imposing 2 zeros texture into the obtained neutrino mass matrix from modified tribimaximal mixing matrix, we then have the neutrino mass spectrum in normal hierarchy. Some phenomenological implications are also discussed. It appears that if we use the solar neutrino squared-mass difference to determine the values of neutrino masses, then we cannot have the correct value for the atmospheric squared-mass difference. Conversely, if we use the experimental value of the squared-mass difference to determine the neutrino masses, then we cannot have the correct value for the solar neutrino squared-mass difference

Hybrid method to resolve the neutrino mass hierarchy by supernova (anti)neutrino induced reactions

Science.gov (United States)

Vale, D.; Rauscher, T.; Paar, N.

2016-02-01

We introduce a hybrid method to determine the neutrino mass hierarchy by simultaneous measurements of responses of at least two detectors to antineutrino and neutrino fluxes from accretion and cooling phases of core-collapse supernovae. The (anti)neutrino-nucleus cross sections for 56Fe and 208Pb are calculated in the framework of the relativistic nuclear energy density functional and weak interaction Hamiltonian, while the cross sections for inelastic scattering on free protons p(bar nue,e+)n are obtained using heavy-baryon chiral perturbation theory. The modelling of (anti)neutrino fluxes emitted from a protoneutron star in a core-collapse supernova include collective and Mikheyev-Smirnov-Wolfenstein effects inside the exploding star. The particle emission rates from the elementary decay modes of the daughter nuclei are calculated for normal and inverted neutrino mass hierarchy. It is shown that simultaneous use of (anti)neutrino detectors with different target material allows to determine the neutrino mass hierarchy from the ratios of νe- and bar nue-induced particle emissions. This hybrid method favors neutrinos from the supernova cooling phase and the implementation of detectors with heavier target nuclei (208Pb) for the neutrino sector, while for antineutrinos the use of free protons in mineral oil or water is the appropriate choice.

Observation of oscillations of atmospheric neutrinos with the IceCube Neutrino Observatory

International Nuclear Information System (INIS)

Euler, Sebastian

2014-01-01

Neutrino oscillations have become one of the most important research topics in particle physics since their discovery 15 years ago. In the past, the study of neutrino oscillations has been largely the domain of dedicated experiments, but in the last year also the large-volume neutrino telescopes ANTARES and IceCube reported their results on the oscillations of atmospheric muon neutrinos and thus joined the community of experiments studying neutrino oscillations. The precision of their results is not yet competitive, but their sheer size and the consequently enormous statistics give rise to the expectation of a competitive measurement in the future. This thesis describes an analysis that was done on IceCube data taken with the nearly complete detector in the years 2010/2011. IceCube is the world's largest neutrino detector, located at the geographic South Pole, where it uses the Antarctic ice sheet as its detection medium. It detects neutrinos interacting within or close to the instrumented volume by observing the Cherenkov light which is emitted by secondary particles produced in these interactions. An array of optical sensors deployed within a cubic kilometer of ice detects the Cherenkov light and makes it possible to reconstruct the energy and direction of the initial neutrino. Unfortunately, IceCube detects not only neutrinos: the desired neutrino signal is buried in a huge background of atmospheric muons, produced in air showers induced by cosmic rays. This background has to be rejected first. The analysis presented here employs an event selection that is based on the idea of using the outer layers of IceCube as an active veto against the background of atmospheric muons and achieves the necessary background rejection of more than 6 orders of magnitude while keeping a high-statistics sample of several thousands of muon neutrinos. In contrast to the earlier IceCube analysis, which used only the zenith angle, it then performs a 2-dimensional likelihood fit on

The physics of massive neutrinos

CERN Document Server

Kayser, Boris; Perrier, Frederic

1989-01-01

This book explains the physics and phenomenology of massive neutrinos. The authors argue that neutrino mass is not unlikely and consider briefly the search for evidence of this mass in decay processes before they examine the physics and phenomenology of neutrino oscillation. The physics of Majorana neutrinos (neutrinos which are their own antiparticles) is then discussed. This volume requires of the reader only a knowledge of quantum mechanics and of very elementary quantum field theory.

Two Light Sterile Neutrinos that Mix Maximally with Each Other and Moderately with Three Active Neutrinos

International Nuclear Information System (INIS)

Krolikowski, W.

2004-01-01

Since the 3+1 neutrino models with one light sterile neutrino turn out to be not very effective, at least two light sterile neutrinos may be needed to reconcile the solar and atmospheric neutrino experiments with the LSND result, if this is confirmed by the ongoing MiniBooNE experiment (and when the CPT invariance is assumed to hold for neutrino oscillations). We present an attractive 3+2 neutrino model, where two light sterile neutrinos mix maximally with each other, in analogy to the observed maximal mixing of muon and tauon active neutrinos. But, while the mixing of ν e and (ν μ - ν τ )/√2 is observed as large (though not maximal), the mixing of ν e with the corresponding combination of two light sterile neutrinos is expected to be only moderate because of the reported smallness of LSND oscillation amplitude. The presented model turns out, however, not to be more effective in explaining the hypothetic LSND result than the simplest 3+1 neutrino model. On the other hand, in the considered 3+2 model, the deviations from conventional oscillations of three active neutrinos appear to be minimal within a larger class of 3+2 models. (author)

Neutrino disintegration of deuterium

International Nuclear Information System (INIS)

Ying, S.; Haxton, W.; Henley, E.M.

1989-01-01

We calculate the rate of both neutral- and charged-current neutrino and antineutrino disintegration of deuterium. These rates are of interest for solar 8 B and hep ( 3 He + p) spectra and supernovae neutrinos, and are relevant for the Sudbury Neutrino Observatory (SNO)

Simulating nonlinear neutrino flavor evolution

Energy Technology Data Exchange (ETDEWEB)

Duan, H [Institute for Nuclear Theory, University of Washington, Seattle, WA 98195 (United States); Fuller, G M [Department of Physics, University of California, San Diego, La Jolla, CA 92093 (United States); Carlson, J [Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)], E-mail: hduan@phys.washington.edu, E-mail: gfuller@ucsd.edu, E-mail: carlson@lanl.gov

2008-10-01

We discuss a new kind of astrophysical transport problem: the coherent evolution of neutrino flavor in core collapse supernovae. Solution of this problem requires a numerical approach which can simulate accurately the quantum mechanical coupling of intersecting neutrino trajectories and the associated nonlinearity which characterizes neutrino flavor conversion. We describe here the two codes developed to attack this problem. We also describe the surprising phenomena revealed by these numerical calculations. Chief among these is that the nonlinearities in the problem can engineer neutrino flavor transformation which is dramatically different to that in standard Mikheyev-Smirnov-Wolfenstein treatments. This happens even though the neutrino mass-squared differences are measured to be small, and even when neutrino self-coupling is sub-dominant. Our numerical work has revealed potential signatures which, if detected in the neutrino burst from a Galactic core collapse event, could reveal heretofore unmeasurable properties of the neutrinos, such as the mass hierarchy and vacuum mixing angle {theta}{sub 13}.

Simulating nonlinear neutrino flavor evolution

Science.gov (United States)

Duan, H.; Fuller, G. M.; Carlson, J.

2008-10-01

We discuss a new kind of astrophysical transport problem: the coherent evolution of neutrino flavor in core collapse supernovae. Solution of this problem requires a numerical approach which can simulate accurately the quantum mechanical coupling of intersecting neutrino trajectories and the associated nonlinearity which characterizes neutrino flavor conversion. We describe here the two codes developed to attack this problem. We also describe the surprising phenomena revealed by these numerical calculations. Chief among these is that the nonlinearities in the problem can engineer neutrino flavor transformation which is dramatically different to that in standard Mikheyev Smirnov Wolfenstein treatments. This happens even though the neutrino mass-squared differences are measured to be small, and even when neutrino self-coupling is sub-dominant. Our numerical work has revealed potential signatures which, if detected in the neutrino burst from a Galactic core collapse event, could reveal heretofore unmeasurable properties of the neutrinos, such as the mass hierarchy and vacuum mixing angle θ13.

Neutrino oscillations at proton accelerators

International Nuclear Information System (INIS)

Michael, Douglas

2002-01-01

Data from many different experiments have started to build a first glimpse of the phenomenology associated with neutrino oscillations. Results on atmospheric and solar neutrinos are particularly clear while a third result from LSND suggests a possibly very complex oscillation phenomenology. As impressive as the results from current experiments are, it is clear that we are just getting started on a long-term experimental program to understand neutrino masses, mixings and the physics which produce them. A number of exciting fundamental physics possibilities exist, including that neutrino oscillations could demonstrate CP or CPT violation and could be tied to exotic high-energy phenomena including strings and extra dimensions. A complete exploration of oscillation phenomena demands many experiments, including those possible using neutrino beams produced at high energy proton accelerators. Most existing neutrino experiments are statistics limited even though they use gigantic detectors. High intensity proton beams are essential for producing the intense neutrino beams which we need for next generation neutrino oscillation experiments

Neutrino Oscillations at Proton Accelerators

Science.gov (United States)

Michael, Douglas

2002-12-01

Data from many different experiments have started to build a first glimpse of the phenomenology associated with neutrino oscillations. Results on atmospheric and solar neutrinos are particularly clear while a third result from LSND suggests a possibly very complex oscillation phenomenology. As impressive as the results from current experiments are, it is clear that we are just getting started on a long-term experimental program to understand neutrino masses, mixings and the physics which produce them. A number of exciting fundamental physics possibilities exist, including that neutrino oscillations could demonstrate CP or CPT violation and could be tied to exotic high-energy phenomena including strings and extra dimensions. A complete exploration of oscillation phenomena demands many experiments, including those possible using neutrino beams produced at high energy proton accelerators. Most existing neutrino experiments are statistics limited even though they use gigantic detectors. High intensity proton beams are essential for producing the intense neutrino beams which we need for next generation neutrino oscillation experiments.

Applying Bayesian neural networks to separate neutrino events from backgrounds in reactor neutrino experiments

International Nuclear Information System (INIS)

Xu, Y; Meng, Y X; Xu, W W

2008-01-01

A toy detector has been designed to simulate central detectors in reactor neutrino experiments in the paper. The samples of neutrino events and three major backgrounds from the Monte-Carlo simulation of the toy detector are generated in the signal region. The Bayesian Neural Networks (BNN) are applied to separate neutrino events from backgrounds in reactor neutrino experiments. As a result, the most neutrino events and uncorrelated background events in the signal region can be identified with BNN, and the part events each of the fast neutron and 8 He/ 9 Li backgrounds in the signal region can be identified with BNN. Then, the signal to noise ratio in the signal region is enhanced with BNN. The neutrino discrimination increases with the increase of the neutrino rate in the training sample. However, the background discriminations decrease with the decrease of the background rate in the training sample

Sterile Neutrino Search with MINOS

Energy Technology Data Exchange (ETDEWEB)

Devan, Alena V. [College of William and Mary, Williamsburg, VA (United States)

2015-08-01

MINOS, Main Injector Neutrino Oscillation Search, is a long-baseline neutrino oscillation experiment in the NuMI muon neutrino beam at the Fermi National Accelerator Laboratory in Batavia, IL. It consists of two detectors, a near detector positioned 1 km from the source of the beam and a far detector 734 km away in Minnesota. MINOS is primarily designed to observe muon neutrino disappearance resulting from three flavor oscillations. The Standard Model of Particle Physics predicts that neutrinos oscillate between three active flavors as they propagate through space. This means that a muon-type neutrino has a certain probability to later interact as a different type of neutrino. In the standard picture, the neutrino oscillation probabilities depend only on three neutrino flavors and two mass splittings, Δm². An anomaly was observed by the LSND and MiniBooNE experiments that suggests the existence of a fourth, sterile neutrino flavor that does not interact through any of the known Standard Model interactions. Oscillations into a theoretical sterile flavor may be observed by a deficit in neutral current interactions in the MINOS detectors. A distortion in the charged current energy spectrum might also be visible if oscillations into the sterile flavor are driven by a large mass-squared difference, m_s² ~ 1 eV². The results of the 2013 sterile neutrino search are presented here.

Metodologia de um ensaio não destrutivo, baseado em medidas de tensão Hall, para determinação de descontinuidades em aços ao carbono

Directory of Open Access Journals (Sweden)

Rayssa Sousa de Andrade Toscano Lins

2015-06-01

Full Text Available Os ensaios não destrutivos são usados para avaliar a presença de descontinuidades que possam afetar a integridade de materiais em serviço. Esse é o motivo principal pelo qual eles são usados em manutenção para detectar defeitos. No presente trabalho, é estudada a potencialidade do uso da interação entre densidades de linhas de campo magnético e material para detecção de descontinuidades. Foram utilizadas para ensaio duas amostras de um aço SAE 1020 laminado, com dimensões de 30x40x12 mm – uma amostra sem furo e outra com um furo passante de 2 mm no centro da face de 30x40 mm. Essas amostras foram submetidas a campos externos de até 18,6 Oe. Um sensor de efeito Hall do tipo SS495A foi utilizado para medições das densidades das linhas de campo resultantes da interação entre o campo e o material. Os resultados mostram que a mudança de permeabilidade de um material em função da presença de uma descontinuidade pode ser detectada através das variações de medidas de densidade de linhas de campo. Um defeito padrão de 2 mm, utilizado em ensaios de ultrassom, foi detectado com a metodologia apresentada. A condição de detecção da descontinuidade para os diferentes aços ao carbono comum foi determinada a partir da aplicação do campo externo ideal encontrado.

Detection of supernova neutrinos with neutrino-iron scattering

International Nuclear Information System (INIS)

Samana, A. R.; Bertulani, C. A.

2008-01-01

The ν e - 56 Fe cross section is evaluated in the projected quasiparticle random phase approximation (PQRPA). This model solves the puzzle observed in RPA for nuclei with mass around 12 C, because it is the only RPA model that treats the Pauli Principle correctly. The cross sections as a function of the incident neutrino energy are compared with recent theoretical calculations of similar models. The average cross section weighted with the flux spectrum yields a good agreement with the experimental data. The expected number of events in the detection of supernova neutrinos is calculated for the LVD detector, leading to an upper limit for the electron neutrino energy of particular importance in this experiment

Experimental data on solar neutrinos

Energy Technology Data Exchange (ETDEWEB)

Ludhova, Livia [INFN, Milano (Italy)

2016-04-15

Neutrino physics continues to be a very active research field, full of opened fundamental questions reaching even beyond the Standard Model of elementary particles and towards a possible new physics. Solar neutrinos have played a fundamental historical role in the discovery of the phenomenon of neutrino oscillations and thus non-zero neutrino mass. Even today, the study of solar neutrinos provides an important insight both into the neutrino as well as into the stellar and solar physics. In this section we give an overview of the most important solar-neutrino measurements from the historical ones up to the most recent ones. We cover the results from the experiments using radio-chemic (Homestake, SAGE, GNO, GALLEX), water Cherenkov (Kamiokande, Super-Kamiokande, SNO), and the liquid-scintillator (Borexino, KamLAND) detection techniques. (orig.)

Rapid method for the sequential measurement of isotopes of Am and Pu in liquid matrices by alpha spectrometry; Método rápido para la medida secuencial de isótopos de Am y Pu en matrices líquidas por espectrometría alfa

Energy Technology Data Exchange (ETDEWEB)

Mantero Cabrera, J.

2014-07-01

: In radiological emergencies it's necessary a fast response from the laboratories in the quantification of certain radionuclides, in order to take decisions. In these cases, is the reaction time the key parameter to consider (without neglecting the quality of the measurement). In this work, it is shown a method for aqueous matrices that generates Pu and Am isotopes sources in one single day of work, to be measured subsequently by alpha spectrometry. The developed methodology has been validated through its application to reference samples and also taking part intercom- parison exercises, having in both cases, satisfactory results. This way, we check the validity of this fast method that let us generate in 24 hours (since the sample arrives our laboratory), one measurement with a Minimun Detectable Activity (MDA) of about 0.004Bq/L for Pu and Am isotopes in liquid matrices. [Spanish] En situaciones de emergencia radiológica es muy común la necesidad de dar una respuesta rápida por parte de los laboratorios en la cuantificación de ciertos radionucleidos, de cara a la toma de decisiones. En estos casos, el tiempo de reacción es una variable fundamental a considerar (aunque obviamente sin dejar de lado la calidad en el resultado de la medida). En este trabajo se presenta un método para matrices acuosas que permite generar en una única jornada de trabajo, las fuentes de medida necesarias en la detección de isótopos de Pu y Am para ser medidas con posterioridad por espectrometría alfa. La metodología puesta a punto ha sido validada mediante su aplicación a muestras de referencia y mediante la participación en ejercicios de intercomparación, en ambos casos, con resultados satisfactorios. Queda así demostrada la validez de este método rápido que nos permite generar en 24 horas desde la recepción de la muestra, una medida en nuestros sistemas con una Actividad Mínima Detectable (AMD) de 0.004 Bq/L tanto para isótopos de Pu (238Pu, 239+240Pu) como de

Effects of neutrino oscillation on supernova neutrino: inverted mass hierarchy

International Nuclear Information System (INIS)

Takahashi, Keitaro; Sato, Katsuhiko

2003-01-01

We study the effects of neutrino oscillation on supernova neutrino in the case of the inverted mass hierarchy (m 3 1 2 ). This is an extended study of our previous study where all analyses are performed with normal mass hierarchy (m 1 2 3 ). Numerical analysis using a realistic supernova and presupernova model allow us to discuss quantitatively a possibility to probe neutrino oscillation parameters. We show that we can break partly the degeneracy of the solar neutrino problem (LMA or SMA) and probe the magnitude of θ 13 to some extent by the ratios of high-energy events and low-energy events at SuperKamiokande and SNO and the presence of the Earth effects. Further, if the magnitude of θ 13 is known roughly, we can identify the mass hierarchy

Search for a diffuse flux of extragalactic neutrinos with the IceCube neutrino observatory

International Nuclear Information System (INIS)

Schukraft, Anne

2013-01-01

Since the discovery of cosmic rays it has been one of the major research goals to identify the sources and acceleration mechanisms behind these high-energy particles observed from space, with energies up to several EeV. The study of high-energy charged particles and photons has advantages and disadvantages: the detection techniques for charged cosmic rays are very advanced though high-energy charged nuclei are not able to reveal their sources due to magnetic deflection. In the last years, there have been discoveries of many gamma-ray sources, where photon fluxes up to energies of 100 TeV have been observed. However, the universe is opaque to photons with energies larger than 100 TeV since gamma rays interact with the cosmic microwave background. Neutrinos suffer from neither of these limitations. They are ideal messenger particles in order to investigate the sources of cosmic rays since they propagate unaffected, but their detection is difficult and no extraterrestrial neutrino sources at high energies have yet been found. The IceCube experiment, located at the geographic South Pole, was built in order to detect high-energy neutrinos from the universe. It was completed in December 2010 and is the largest neutrino observatory on Earth. It detects neutrinos via their interaction with the Antarctic ice inside and around the detection volume. In these interactions, high-energy leptons are produced, which follow the direction of the initial neutrino and produce a cone of Cherenkov light along their path. This light is detected by optical sensors deployed in the instrumented volume. The search for a diffuse neutrino flux is a very promising approach to look for an extragalactic flux of astrophysical neutrinos. Its sensitivity is mainly based on neutrino energies since astrophysical neutrinos are expected to be more energetic than atmospheric neutrinos. It searches for an astrophysical flux from the sum of all sources in the universe. These sources can be individually

Search for a diffuse flux of extragalactic neutrinos with the IceCube neutrino observatory

Energy Technology Data Exchange (ETDEWEB)

Schukraft, Anne

2013-06-07

Since the discovery of cosmic rays it has been one of the major research goals to identify the sources and acceleration mechanisms behind these high-energy particles observed from space, with energies up to several EeV. The study of high-energy charged particles and photons has advantages and disadvantages: the detection techniques for charged cosmic rays are very advanced though high-energy charged nuclei are not able to reveal their sources due to magnetic deflection. In the last years, there have been discoveries of many gamma-ray sources, where photon fluxes up to energies of 100 TeV have been observed. However, the universe is opaque to photons with energies larger than 100 TeV since gamma rays interact with the cosmic microwave background. Neutrinos suffer from neither of these limitations. They are ideal messenger particles in order to investigate the sources of cosmic rays since they propagate unaffected, but their detection is difficult and no extraterrestrial neutrino sources at high energies have yet been found. The IceCube experiment, located at the geographic South Pole, was built in order to detect high-energy neutrinos from the universe. It was completed in December 2010 and is the largest neutrino observatory on Earth. It detects neutrinos via their interaction with the Antarctic ice inside and around the detection volume. In these interactions, high-energy leptons are produced, which follow the direction of the initial neutrino and produce a cone of Cherenkov light along their path. This light is detected by optical sensors deployed in the instrumented volume. The search for a diffuse neutrino flux is a very promising approach to look for an extragalactic flux of astrophysical neutrinos. Its sensitivity is mainly based on neutrino energies since astrophysical neutrinos are expected to be more energetic than atmospheric neutrinos. It searches for an astrophysical flux from the sum of all sources in the universe. These sources can be individually

Observing Muon Neutrino to Electron Neutrino Oscillations in the NOνA Experiment

Energy Technology Data Exchange (ETDEWEB)

Xin, Tian [Iowa State U.

2016-01-01

Neutrino oscillations offers an insight on new physics beyond the Standard Model. The three mixing angles (θ12, θ13 and θ23) and the two mass splittings (Δm2 and Αm2 ) have been measured by different neutrino oscillation experiments. Some other parameters including the mass ordering of different neutrino mass eigenstates and the CP violation phase are still unknown. NOνA is a long-baseline accelerator neutrino experiment, using neutrinos from the NuMI beam at Fermilab. The experiment is equipped with two functionally identical detectors about 810 kilometers apart and 14 mrad off the beam axis. In this configuration, the muon neutrinos from the NuMI beam reach the disappearance maximum in the far detector and a small fraction of that oscillates into electron neutrinos. The sensitivity to the mass ordering and CP viola- tion phase determination is greately enhanced. This thesis presents the νeappearance analysis using the neutrino data collected with the NOνA experiment between February 2014 and May 2015, which corresponds to 3.45 ×1020 protons-on-target (POT). The νe appearance analysis is performed by comparing the observed νe CC-like events to the estimated background at the far detector. The total background is predicted to be 0.95 events with 0.89 originated from beam events and 0.06 from cosmic ray events. The beam background is obtained by extrapolating near detector data through different oscillation channels, while the cosmic ray background is calculated based on out-of-time NuMI trigger data. A total of 6 electron neutrino candidates are observed in the end at the far detector which represents 3.3 σ excess over the predicted background. The NOνA result disfavors inverted mass hierarchy for δcp ϵ [0, 0.6π] at 90% C.L.

Matter effects on the flavor conversions of solar neutrinos and high-energy astrophysical neutrinos

Science.gov (United States)

Huang, Guo-yuan; Liu, Jun-Hao; Zhou, Shun

2018-06-01

Can we observe the solar eclipses in the neutrino light? In principle, this is possible by identifying the lunar matter effects on the flavor conversions of solar neutrinos when they traverse the Moon before reaching the detectors at the Earth. Unfortunately, we show that the lunar matter effects on the survival probability of solar 8B neutrinos are suppressed by an additional factor of 1.2%, compared to the day-night asymmetry. However, we point out that the matter effects on the flavor conversions of high-energy astrophysical neutrinos, when they propagate through the Sun, can be significant. Though the flavor composition of high-energy neutrinos can be remarkably modified, it is quite challenging to observe such effects even in the next-generation of neutrino telescopes.

Neutrino mass hierarchy and three-flavor spectral splits of supernova neutrinos

International Nuclear Information System (INIS)

Dasgupta, Basudeb; Mirizzi, Alessandro; Tomas, Ricard; Tamborra, Irene

2010-01-01

It was recently realized that three-flavor effects could peculiarly modify the development of spectral splits induced by collective oscillations, for supernova neutrinos emitted during the cooling phase of a protoneutron star. We systematically explore this case, explaining how the impact of these three-flavor effects depends on the ordering of the neutrino masses. In inverted mass hierarchy, the solar mass splitting gives rise to instabilities in regions of the (anti)neutrino energy spectra that were otherwise stable under the leading two-flavor evolution governed by the atmospheric mass splitting and by the 1-3 mixing angle. As a consequence, the high-energy spectral splits found in the electron (anti)neutrino spectra disappear, and are transferred to other flavors. Imperfect adiabaticity leads to smearing of spectral swap features. In normal mass hierarchy, the three-flavor and the two-flavor instabilities act in the same region of the neutrino energy spectrum, leading to only minor departures from the two-flavor treatment.

Supernova relic electron neutrinos and anti-neutrinos in future large-scale observatories

Energy Technology Data Exchange (ETDEWEB)

Volpe, C.; Welzel, J. [Institut de Physique Nuclueaire, 91 - Orsay (France)

2007-07-01

We investigate the signal from supernova relic neutrinos in future large scale observatories, such as MEMPHYS (UNO, Hyper-K), LENA and GLACIER, at present under study. We discuss that complementary information might be gained from the observation of supernova relic electron antineutrinos and neutrinos using the scattering on protons on one hand, and on nuclei such as oxygen, carbon or argon on the other hand. When determining the relic neutrino fluxes we also include, for the first time, the coupling of the neutrino magnetic moment to magnetic fields within the core collapse supernova. We present numerical results on both the relic {nu}{sub e} and {nu}-bar{sub e} fluxes and on the number of events for {nu}{sub e} + C{sup 12}, {nu}{sub e} + O{sup 16}, {nu}{sub e} + Ar{sup 40} and {nu}-bar{sub e} + p for various oscillation scenarios. The observation of supernova relic neutrinos might provide us with unique information on core-collapse supernova explosions, on the star formation history and on neutrino properties, that still remain unknown. (authors)

A comprehensive study of neutrino spin-flavour conversion in supernovae and the neutrino mass hierarchy

Science.gov (United States)

Ando, Shin'ichiro; Sato, Katsuhiko

2003-10-01

Resonant spin-flavour (RSF) conversions of supernova neutrinos, which are induced by the interaction between the nonzero neutrino magnetic moment and supernova magnetic fields, are studied for both normal and inverted mass hierarchy. As the case for the pure matter-induced neutrino oscillation (Mikheyev–Smirnov–Wolfenstein (MSW) effect), we find that the RSF transitions are strongly dependent on the neutrino mass hierarchy as well as the value of θ13. Flavour conversions are solved numerically for various neutrino parameter sets, with the presupernova profile calculated by Woosley and Weaver. In particular, it is very interesting that the RSF-induced νe→bar nue transition occurs if the following conditions are all satisfied: the value of μνB (μν is the neutrino magnetic moment and B is the magnetic field strength) is sufficiently strong, the neutrino mass hierarchy is inverted, and the value of θ13 is large enough to induce adiabatic MSW resonance. In this case, the strong peak due to the original νe emitted from the neutronization burst would exist in the time profile of the neutrino events detected at the Super-Kamiokande detector. If this peak were observed in reality, it would provide fruitful information on the neutrino properties. On the other hand, the characteristics of the neutrino spectra are also different between the neutrino models, but we find that there remains degeneracy among several models. Dependence on presupernova models is also discussed.

Status and aims of the DUMAND neutrino project: the ocean as a neutrino detector

International Nuclear Information System (INIS)

Roberts, A.; Blood, H.; Learned, J.; Reines, F.

1976-07-01

The possibility of using the ocean as a neutrino detector is considered. Neutrino-produced interactions result in charged particles that generate Cherenkov radiation in the water, which can be detected by light-gathering equipment and photomultipliers. The properties of the ocean as seen from this standpoint are critically examined, and the advantages and disadvantages pointed out. Possible uses for such a neutrino detector include (1) the detection of neutrinos emitted in gravitational collapse of stars (supernova production), not only in our own galaxy, but in other galaxies up to perhaps twenty-million light-years away, (2) the extension of high-energy neutrino physics, as currently practiced up to 200 GeV at high-energy accelerators, to energies up to 50 times higher, using neutrinos generated in the atmosphere by cosmic rays, and (3) the possible detection of neutrinos produced by cosmic-ray interactions outside the earth's atmosphere. The technology for such an undertaking seems to be within reach

Status and Aims of the DUMAND Neutrino Project: the Ocean as a Neutrino Detector

Science.gov (United States)

Roberts, A.; Blood, H.; Learned, J.; Reines, F.

1976-07-01

The possibility of using the ocean as a neutrino detector is considered. Neutrino-produced interactions result in charged particles that generate Cherenkov radiation in the water, which can be detected by light-gathering equipment and photomultipliers. The properties of the ocean as seen from this standpoint are critically examined, and the advantages and disadvantages pointed out. Possible uses for such a neutrino detector include (1) the detection of neutrinos emitted in gravitational collapse of stars (supernova production), not only in our own galaxy, but in other galaxies up to perhaps twenty-million light-years away, (2) the extension of high-energy neutrino physics, as currently practiced up to 200 GeV at high-energy accelerators, to energies up to 50 times higher, using neutrinos generated in the atmosphere by cosmic rays, and (3) the possible detection of neutrinos produced by cosmic-ray interactions outside the earth`s atmosphere. The technology for such an undertaking seems to be within reach.

Efeito da orientação para o mercado sobre a lucratividade da empresa

OpenAIRE

Narver,John C.; Slater,Stanley F.

2006-01-01

Acadêmicos e profissionais de marketing vêm observando, há mais de três décadas, que o desempenho empresarial é afetado pela orientação para o mercado, mas até hoje não há uma medida válida da orientação para o mercado nem análise sistemática de seu efeito sobre o desempenho das empresas. Os autores relatam o desenvolvimento de uma medida válida de orientação para o mercado e analisam seu efeito sobre a lucratividade de uma empresa. Usando uma amostra de 140 unidades de negócio composta de em...

Flavor ratios of extragalactic neutrinos and neutrino shortcuts in extra dimensions

Energy Technology Data Exchange (ETDEWEB)

Aeikens, Elke; Päs, Heinrich [Fakultät für Physik, Technische Universität Dortmund,44221 Dortmund (Germany); Pakvasa, Sandip [Department of Physics & Astronomy, University of Hawaii,Honolulu, HI 96822 (United States); Sicking, Philipp [Fakultät für Physik, Technische Universität Dortmund,44221 Dortmund (Germany)

2015-10-02

The recent measurement of high energy extragalactic neutrinos by the IceCube Collaboration has opened a new window to probe non-standard neutrino properties. Among other effects, sterile neutrino altered dispersion relations (ADRs) due to shortcuts in an extra dimension can significantly affect astrophysical flavor ratios. We discuss two limiting cases of this effect, first active-sterile neutrino oscillations with a constant ADR potential and second an MSW-like resonant conversion arising from geodesics oscillating around the brane in an asymmetrically warped extra dimension. We demonstrate that the second case has the potential to suppress significantly the flux of specific flavors such as ν{sub μ} or ν{sub τ} at high energies.

Flavor ratios of extragalactic neutrinos and neutrino shortcuts in extra dimensions

Energy Technology Data Exchange (ETDEWEB)

Aeikens, Elke; Päs, Heinrich; Sicking, Philipp [Fakultät für Physik, Technische Universität Dortmund, 44221 Dortmund (Germany); Pakvasa, Sandip, E-mail: elke.aeikens@tu-dortmund.de, E-mail: heinrich.paes@tu-dortmund.de, E-mail: pakvasa@phys.hawaii.edu, E-mail: philipp.sicking@tu-dortmund.de [Department of Physics and Astronomy, University of Hawaii, Honolulu, HI 96822 (United States)

2015-10-01

The recent measurement of high energy extragalactic neutrinos by the IceCube Collaboration has opened a new window to probe non-standard neutrino properties. Among other effects, sterile neutrino altered dispersion relations (ADRs) due to shortcuts in an extra dimension can significantly affect astrophysical flavor ratios. We discuss two limiting cases of this effect, first active-sterile neutrino oscillations with a constant ADR potential and second an MSW-like resonant conversion arising from geodesics oscillating around the brane in an asymmetrically warped extra dimension. We demonstrate that the second case has the potential to suppress significantly the flux of specific flavors such as ν{sub μ} or ν{sub τ} at high energies.

Solar neutrinos and the MSW effect for three-neutrino mixing

Science.gov (United States)

Shi, X.; Schramm, David N.

1991-01-01

Researchers considered three-neutrino Mikheyev-Smirnov-Wolfenstein (MSW) mixing, assuming m sub 3 is much greater than m sub 2 is greater than m sub 1 as expected from theoretical consideration if neutrinos have mass. They calculated the corresponding mixing parameter space allowed by the Cl-37 and Kamiokande 2 experiments. They also calculated the expected depletion for the Ga-71 experiment. They explored a range of theoretical uncertainty due to possible astrophysical effects by varying the B-8 neutrino flux and redoing the MSW mixing calculation.

Densidade global de solos medida com anel volumétrico e por cachimbagem de terra fina seca ao ar Bulk density of soil samples measured in the field and through volume measurement of sieved soil

Directory of Open Access Journals (Sweden)

Bernardo Van Raij

1989-01-01

Full Text Available Em laboratórios de rotina de fertilidade do solo, a medida de quantidade de terra para análise é feita em volume, mediante utensílios chamados "cachimbos", que permitem medir volumes de terra. Admite-se que essas medidas reflitam a quantidade de terra existente em volume de solo similar em condições de campo. Essa hipótese foi avaliada neste trabalho, por doze amostras dos horizontes A e B de seis perfis de solos. A densidade em condições de campo foi avaliada por anel volumétrico e, no laboratório, por meio de cachimbos de diversos tamanhos. A cachimbagem revelou-se bastante precisa. Os valores de densidade global calculada variaram de 0,63 a 1,46g/cm³ para medidas de campo e de 0,91 a 1,33g/cm³ para medidas com cachimbos. Portanto, a medida de laboratório subestimou valores altos de densidade e deu resultados mais elevados para valores de campo mais baixos.In soil testing laboratories, soil samples for chemical analysis are usually measured by volume, using appropriate measuring spoons. It is tacitly assumed that such measurements would reflect amounts of soil existing in the same volume under field conditions. This hypothesis was tested, using 12 soil samples of the A and B horizons of six soil profiles. Bulk density in the field was evaluated through a cylindrical metal sampler of 50cm³ and in the laboratory using spoons of different sizes. Measurements of soil volumes by spoons were quite precise. Values of bulk density varied between 0.63 and 1.46g/cm³ for field measurements and between 0.91 and 1.33g/cm³ for laboratory measurements with spoons. Thus, laboratory measurements overestimated lower values of bulk densities and underestimated the higher ones.

Hybrid method to resolve the neutrino mass hierarchy by supernova (anti)neutrino induced reactions

Energy Technology Data Exchange (ETDEWEB)

Vale, D. [Department of Physics, Faculty of Science, University of Zagreb, Bijenička c. 32, HR-10000 Zagreb (Croatia); Rauscher, T. [Centre for Astrophysics Research, University of Hertfordshire, College Lane, Hatfield AL10 9AB (United Kingdom); Paar, N., E-mail: dvale@phy.hr, E-mail: Thomas.Rauscher@unibas.ch, E-mail: npaar@phy.hr [Department of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel (Switzerland)

2016-02-01

We introduce a hybrid method to determine the neutrino mass hierarchy by simultaneous measurements of responses of at least two detectors to antineutrino and neutrino fluxes from accretion and cooling phases of core-collapse supernovae. The (anti)neutrino-nucleus cross sections for {sup 56}Fe and {sup 208}Pb are calculated in the framework of the relativistic nuclear energy density functional and weak interaction Hamiltonian, while the cross sections for inelastic scattering on free protons p(ν-bar {sub e},e{sup +})n are obtained using heavy-baryon chiral perturbation theory. The modelling of (anti)neutrino fluxes emitted from a protoneutron star in a core-collapse supernova include collective and Mikheyev-Smirnov-Wolfenstein effects inside the exploding star. The particle emission rates from the elementary decay modes of the daughter nuclei are calculated for normal and inverted neutrino mass hierarchy. It is shown that simultaneous use of (anti)neutrino detectors with different target material allows to determine the neutrino mass hierarchy from the ratios of ν{sub e}- and ν-bar {sub e}-induced particle emissions. This hybrid method favors neutrinos from the supernova cooling phase and the implementation of detectors with heavier target nuclei ({sup 208}Pb) for the neutrino sector, while for antineutrinos the use of free protons in mineral oil or water is the appropriate choice.

Looking for Cosmic Neutrino Background

Directory of Open Access Journals (Sweden)

Chiaki eYanagisawa

2014-06-01

Full Text Available Since the discovery of neutrino oscillation in atmospheric neutrinos by the Super-Kamiokande experiment in 1998, study of neutrinos has been one of exciting fields in high-energy physics. All the mixing angles were measured. Quests for 1 measurements of the remaining parameters, the lightest neutrino mass, the CP violating phase(s, and the sign of mass splitting between the mass eigenstates m3 and m1, and 2 better measurements to determine whether the mixing angle theta23 is less than pi/4, are in progress in a well-controlled manner. Determining the nature of neutrinos, whether they are Dirac or Majorana particles is also in progress with continuous improvement. On the other hand, although the ideas of detecting cosmic neutrino background have been discussed since 1960s, there has not been a serious concerted effort to achieve this goal. One of the reasons is that it is extremely difficult to detect such low energy neutrinos from the Big Bang. While there has been tremendous accumulation of information on Cosmic Microwave Background since its discovery in 1965, there is no direct evidence for Cosmic Neutrino Background. The importance of detecting Cosmic Neutrino Background is that, although detailed studies of Big Bang Nucleosynthesis and Cosmic Microwave Background give information of the early Universe at ~a few minutes old and ~300 k years old, respectively, observation of Cosmic Neutrino Background allows us to study the early Universe at $sim$ 1 sec old. This article reviews progress made in the past 50 years on detection methods of Cosmic Neutrino Background.

Prototipo de dispositivo de medida de rendimiento en running basado en acelerómetro triaxial y comunicación a dispositivo móvil

OpenAIRE

MELIÀ DE LA ASUNCIÓN, SERGI

2016-01-01

[ES] Debido al creciente número de practicantes del deporte conocido de forma vulgar como ‘running’, se ha abierto un gran mercado para las aplicaciones y dispositivos relacionados con la monitorización de esta actividad. La aplicación desarrollada mediante Android, establecerá comunicación con los sensores alojados en el ‘CC2541 SensorTag’ para estudiar su viabilidad como posible puente para la fabricación de posteriores sistemas de medida de rendimiento. Melià De La Asunci...

Particle Astrophysics of Neutrinos

Indian Academy of Sciences (India)

Amol Dighe

Energy spectra of neutrino sources. ASPERA. Page 4. Some unique features of neutrinos. The second most abundant particles in the universe. Cosmic microwave background photons: 400 / cm3. Cosmic background neutrinos: 330 / cm3. The lightest massive particles. A million times lighter than the electron. No direct mass ...

Neutrino mass sum-rule

Science.gov (United States)

Damanik, Asan

2018-03-01

Neutrino mass sum-rele is a very important research subject from theoretical side because neutrino oscillation experiment only gave us two squared-mass differences and three mixing angles. We review neutrino mass sum-rule in literature that have been reported by many authors and discuss its phenomenological implications.

Reflexiones sobre el problema del analfabetismo y propuesta de algunas medidas pedagógicas para combatirlo

Directory of Open Access Journals (Sweden)

Maria José NAVARRO PERALES

2009-11-01

Full Text Available El analfabetismo es la consecuencia de la desigualdad e injusticia social. Combatirlo es una labor igualmente social. Las medidas deben ser tomadas por los gobiernos a través de instituciones de educación formal y no formal. La prevención y desaparición del analfabetismo, en todas sus modalidades y grados, debe realizarse desde el punto de vista del analfabeto y no contra él.

Accelerator-based neutrino oscillation searches

International Nuclear Information System (INIS)

Whitehouse, D.A.; Rameika, R.; Stanton, N.

1993-01-01

This paper attempts to summarize the neutrino oscillation section of the Workshop on Future Directions in Particle and Nuclear Physics at Multi-GeV Hadron Beam Facilities. There were very lively discussions about the merits of the different oscillation channels, experiments, and facilities, but we believe a substantial consensus emerged. First, the next decade is one of great potential for discovery in neutrino physics, but it is also one of great peril. The possibility that neutrino oscillations explain the solar neutrino and atmospheric neutrino experiments, and the indirect evidence that Hot Dark Matter (HDM) in the form of light neutrinos might make up 30% of the mass of the universe, point to areas where accelerator-based experiments could play a crucial role in piecing together the puzzle. At the same time, the field faces a very uncertain future. The LSND experiment at LAMPF is the only funded neutrino oscillation experiment in the United States and it is threatened by the abrupt shutdown of LAMPF proposed for fiscal 1994. The future of neutrino physics at the Brookhaven National Laboratory AGS depends the continuation of High Energy Physics (HEP) funding after the RHIC startup. Most proposed neutrino oscillation searches at Fermilab depend on the completion of the Main Injector project and on the construction of a new neutrino beamline, which is uncertain at this point. The proposed KAON facility at TRIUMF would provide a neutrino beam similar to that at the AGS but with a much increase intensity. The future of KAON is also uncertain. Despite the difficult obstacles present, there is a real possibility that we are on the verge of understanding the masses and mixings of the neutrinos. The physics importance of such a discovery can not be overstated. The current experimental status and future possibilities are discussed below

Neutrino nuclear responses for double beta decays and astro neutrinos by charge exchange reactions

Science.gov (United States)

Ejiri, Hiroyasu

2014-09-01

Neutrino nuclear responses are crucial for neutrino studies in nuclei. Charge exchange reactions (CER) are shown to be used to study charged current neutrino nuclear responses associated with double beta decays(DBD)and astro neutrino interactions. CERs to be used are high energy-resolution (He3 ,t) reactions at RCNP, photonuclear reactions via IAR at NewSUBARU and muon capture reactions at MUSIC RCNP and MLF J-PARC. The Gamow Teller (GT) strengths studied by CERs reproduce the observed 2 neutrino DBD matrix elements. The GT and spin dipole (SD) matrix elements are found to be reduced much due to the nucleon spin isospin correlations and the non-nucleonic (delta isobar) nuclear medium effects. Impacts of the reductions on the DBD matrix elements and astro neutrino interactions are discussed.

Gauge Trimming of Neutrino Masses

International Nuclear Information System (INIS)

Chen, Mu-Chun; de Gouvea, Andre; Dobrescu, Bogdan A.

2006-01-01

We show that under a new U(1) gauge symmetry, which is non-anomalous in the presence of one ''right-handed neutrino'' per generation and consistent with the standard model Yukawa couplings, the most general fermion charges are determined in terms of four rational parameters. This generalization of the B-L symmetry with generation-dependent lepton charges leads to neutrino masses induced by operators of high dimensionality. Neutrino masses are thus naturally small without invoking physics at energies above the TeV scale, whether neutrinos are Majorana or Dirac fermions. This ''Leptocratic'' Model predicts the existence of light quasi-sterile neutrinos with consequences for cosmology, and implies that collider experiments may reveal the origin of neutrino masses

Resonant amplification of neutrino spin rotation in matter and the solar-neutrino problem

International Nuclear Information System (INIS)

Akhmedov, E.Kh.

1988-01-01

It is shown that in the presence of matter there can occur resonant amplification of the flavor-changing neutrino spin rotation in transverse magnetic fields, which is roughly analogous to the Mikheyev-Smirnov-Wolfenstein effect in neutrino oscillations. Possible consequences for solar neutrinos are briefly discussed. (orig.)

Sterile Neutrinos in Cold Climates

Energy Technology Data Exchange (ETDEWEB)

Jones, Benjamin J.P. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)

2015-09-01

Measurements of neutrino oscillations at short baselines contain an intriguing set of experimental anomalies that may be suggestive of new physics such as the existence of sterile neutrinos. This three-part thesis presents research directed towards understanding these anomalies and searching for sterile neutrino oscillations. Part I contains a theoretical discussion of neutrino coherence properties. The open-quantum-system picture of neutrino beams, which allows a rigorous prediction of coherence distances for accelerator neutrinos, is presented. Validity of the standard treatment of active and sterile neutrino oscillations at short baselines is verified, and non-standard coherence loss effects at longer baselines are predicted. Part II concerns liquid argon detector development for the MicroBooNE experiment, which will search for short-baseline oscillations in the Booster Neutrino Beam at Fermilab. Topics include characterization and installation of the MicroBooNE optical system; test-stand measurements of liquid argon optical properties with dissolved impurities; optimization of wavelength-shifting coatings for liquid argon scintillation light detection; testing and deployment of high-voltage surge arrestors to protect TPC field cages; and software development for optical and TPC simulation and reconstruction. Part III presents a search for sterile neutrinos using the IceCube neutrino telescope, which has collected a large sample of atmospheric-neutrino-induced events in the 1-10 TeV energy range. Sterile neutrinos would modify the detected neutrino flux shape via MSW-resonant oscillations. Following a careful treatment of systematic uncertainties in the sample, no evidence for MSW-resonant oscillations is observed, and exclusion limits on 3+1 model parameter space are derived. Under the mixing assumptions made, the 90% confidence level exclusion limit extends to sin²2θ₂₄ ≤ 0.02 at m² ~ 0.3 eV², and the LSND and Mini

Faraday effect and solar neutrino problem

International Nuclear Information System (INIS)

Nawaz, S.

2001-01-01

We have studied the Faraday effect and solar neutrino problem. Our main emphasis was on the Faraday rotation of neutrino de Broglie wave of electron-neutrino producing in the nuclear reactions in the sun and converting into any other flavor of neutrino while passing through matter and/or magnetic field of the sun. We have shown that specific Faraday angle can minimize the number of free parameters occurring in the neutrino oscillation. We have also shown that the resonant Faraday angle corresponding to the resonance of MSW effect can be obtained the knowledge of the oscillation parameter delta m/sup 2/ and the neutrino energy. Using neutrino-Faraday angle approach, we have shown that the matter enhanced neutrino oscillations is dominating over the resonant spin flavor precession (RSFP) even in the favorable region of the spin flavor procession. Using the latest solar neutrino data, we have shown that Faraday angle is almost 10/sup -3/ times smaller. This can be interpreted as the interaction of magnetic moment of neutrino with the solar magnetic field is negligibly small as compare to the effect of matter field on the neutrino oscillation. (author)

Nonstandard neutrino interactions in supernovae

Science.gov (United States)

Stapleford, Charles J.; Väänänen, Daavid J.; Kneller, James P.; McLaughlin, Gail C.; Shapiro, Brandon T.

2016-11-01

Nonstandard interactions (NSI) of neutrinos with matter can significantly alter neutrino flavor evolution in supernovae with the potential to impact explosion dynamics, nucleosynthesis, and the neutrinos signal. In this paper, we explore, both numerically and analytically, the landscape of neutrino flavor transformation effects in supernovae due to NSI and find a new, heretofore unseen transformation processes can occur. These new transformations can take place with NSI strengths well below current experimental limits. Within a broad swath of NSI parameter space, we observe symmetric and standard matter-neutrino resonances for supernovae neutrinos, a transformation effect previously only seen in compact object merger scenarios; in another region of the parameter space we find the NSI can induce neutrino collective effects in scenarios where none would appear with only the standard case of neutrino oscillation physics; and in a third region the NSI can lead to the disappearance of the high density Mikheyev-Smirnov-Wolfenstein resonance. Using a variety of analytical tools, we are able to describe quantitatively the numerical results allowing us to partition the NSI parameter according to the transformation processes observed. Our results indicate nonstandard interactions of supernova neutrinos provide a sensitive probe of beyond the Standard Model physics complementary to present and future terrestrial experiments.

Neutrino oscillations in the early universe

International Nuclear Information System (INIS)

Enqvist, K.

1990-01-01

The oscillations of electron neutrinos into inert neutrinos may have resonant behaviour in the heat bath of the early Universe. It is shown that any initial neutrino asymmetry will be washed away by the oscillations. Neutrino oscillations would affect also primordial helium production, which implies stringent limits on the neutrino mixing parameters. (orig.)

Impact of Neutrino Flavor Oscillations on the Neutrino-driven Wind Nucleosynthesis of an Electron-capture Supernova

Science.gov (United States)

Pllumbi, Else; Tamborra, Irene; Wanajo, Shinya; Janka, Hans-Thomas; Hüdepohl, Lorenz

2015-08-01

Neutrino oscillations, especially to light sterile states, can affect nucleosynthesis yields because of their possible feedback effect on the electron fraction (Ye). For the first time, we perform nucleosynthesis calculations for neutrino-driven wind trajectories from the neutrino-cooling phase of an 8.8 {M}⊙ electron-capture supernova (SN), whose hydrodynamic evolution was computed in spherical symmetry with sophisticated neutrino transport and whose Ye evolution was post-processed by including neutrino oscillations between both active and active-sterile flavors. We also take into account the α-effect as well as weak magnetism and recoil corrections in the neutrino absorption and emission processes. We observe effects on the Ye evolution that depend in a subtle way on the relative radial positions of the sterile Mikheyev-Smirnov-Wolfenstein resonances, on collective flavor transformations, and on the formation of α particles. For the adopted SN progenitor, we find that neutrino oscillations, also to a sterile state with eV mass, do not significantly affect the element formation and in particular cannot make the post-explosion wind outflow neutron-rich enough to activate a strong r-process. Our conclusions become even more robust when, in order to mimic equation-of-state-dependent corrections due to nucleon potential effects in the dense-medium neutrino opacities, six cases with reduced Ye in the wind are considered. In these cases, despite the conversion of active neutrinos to sterile neutrinos, Ye increases or is not significantly lowered compared to the values obtained without oscillations and active flavor transformations. This is a consequence of a complicated interplay between sterile-neutrino production, neutrino-neutrino interactions, and α-effect.

Neutrino properties from cosmology

DEFF Research Database (Denmark)

Hannestad, S.

2013-01-01

In recent years precision cosmology has become an increasingly powerful probe of particle physics. Perhaps the prime example of this is the very stringent cosmological upper bound on the neutrino mass. However, other aspects of neutrino physics, such as their decoupling history and possible non......-standard interactions, can also be probed using observations of cosmic structure. Here, I review the current status of cosmological bounds on neutrino properties and discuss the potential of future observations, for example by the recently approved EUCLID mission, to precisely measure neutrino properties....

Medidas de prevenção contra câncer de pele em trabalhadores da construção civil: contribuição da enfermagem Trabajador de la construcción civil y las medidas de prevención contra cáncer da piel: contribución de la enfermería Building construction worker and preventive measures against skin cancer: nursing contribution

Directory of Open Access Journals (Sweden)

Thiago do Carmo Simões

2011-03-01

Full Text Available Os trabalhadores da construção civil são um dos maiores grupos de risco para o câncer ocupacional. Objetivou-se identificar o conhecimento destes trabalhadores sobre o câncer de pele, descrevendo as medidas de proteção/prevenção adotadas por eles. Estudo descritivo de natureza quantitativa, desenvolvido com 50 trabalhadores de uma empresa de construção civil no município do Rio de Janeiro, sendo os dados coletados por meio de um formulário. Da análise estatística descritiva, verificou-se que as medidas de proteção adotadas pelos trabalhadores para prevenção são insuficientes e a forma como são utilizadas não está em consonância com a literatura para protegê-los desta patologia. As maiores mudanças necessárias no cotidiano destes trabalhadores estão relacionadas com questões no estilo de vida e na facilidade no acesso às informações e conhecimentos quanto ao câncer de pele. Assim, intervenções do enfermeiro com a equipe da Saúde do Trabalhador podem contribuir para implementações de medidas preventivas do câncer ocupacional.Los trabajadores de la construcción civil son un dos mayores grupos de riesgo para el cáncer de piel. El objetivo fue identificar el conocimiento de los trabajadores de la construcción civil sobre el cáncer de piel y describir las medidas de protección/prevención adoptadas para el combat a cáncer de piel. Investigación descriptiva del naturaleza cuantitativa desarrollado con 50 trabajadores de una empresa de construcción civil en la ciudad del Rio de Janeiro, Brasil, donde los datos fueron colectados por un formulario. De la análisis estadística descriptiva, verificó que las medidas de protección adoptadas por el trabajadores para prevención del cáncer de piel son insuficientes para protegerlos desta patología. Las mayores mudanzas necesarias en el cotidiano de estos trabajadores están relacionadas con pregruntas en el estilo de la vida e facilidad en acceso a las

A road map to solar neutrino fluxe, neutrino oscillation parameters, and tests for new physics

CERN Document Server

Bahcall, J N; Bahcall, John N.; Peña-Garay, Carlos

2003-01-01

We analyze all available solar and related reactor neutrino experiments, as well as simulated future ^7Be, p-p, pep, and ^8B solar neutrino experiments. We treat all solar neutrino fluxes as free parameters subject to the condition that the total luminosity represented by the neutrinos equals the observed solar luminosity (the `luminosity constraint'). Existing experiments show that the p-p solar neutrino flux is 1.01 + - 0.02 (1 sigma) times the flux predicted by the BP00 standard solar model; the ^7Be neutrino flux is 0.97^{+0.28}_{-0.54} the predicted flux; and the ^8B flux is 1.01 + - 0.06 the predicted flux. The oscillation parameters are: Delta m^2 = 7.3^{+0.4}_{-0.6} 10^{-5} eV^2 and tan^2 theta_{12} = 0.42^{+0.08}_{-0.06}. We evaluate how accurate future experiments must be to determine more precisely neutrino oscillation parameters and solar neutrino fluxes, and to elucidate the transition from vacuum-dominated to matter-dominated oscillations. A future ^7Be nu-e scattering experiment accurate to + -...

Neutrino Oscillations

Indian Academy of Sciences (India)

work of Takaaki Kajita and Arthur B McDonald clearly demon- strated the ... time belief that neutrinos are massless particles. .... SK is a second generation, 50,000 t wa- ..... values of the parameters of the PMNS matrix based on a global .... [13] Y Ashie et al., Evidence for an oscillatory signature in atmospheric neutrino.

Medidas de bioseguridad adoptadas en el manejo con materiales biológicos en Laboratorios Liorad Biosafety measures adopted in Liorad Laboratories for handling biological materials

Directory of Open Access Journals (Sweden)

Nancy Burguet Lago

2013-03-01

Full Text Available Introducción: el trabajo con microorganismos puede conllevar a riesgos tanto para el personal que trabaja con los mismos como para el medio ambiente. La existencia de laboratorios de seguridad biológica y la implementación de medidas en la manipulación de los agentes biológicos minimizan el riesgo. Objetivo: evaluar las medidas de bioseguridad adoptadas en el manejo con materiales biológicos en Laboratorios Liorad. Métodos: empleo de una lista de chequeo y análisis de los resultados a través de una Matriz DAFO para valorar si el diseño de la instalación cumple con la bioseguridad. Además establecer un sistema documental para la manipulación de microorganismos y la confección de un plan de capacitación para el personal que trabaja en el laboratorio de control microbiológico. Resultados: la lista de chequeo permitió identificar como principal debilidad el no disponer de un doble pasillo para el traslado del material limpio y sucio. Como fortalezas, cumplir con las prácticas y procesamientos adecuados y el contar con equipos de seguridad biológica. El sistema documental incorporó a los procedimientos establecidos para la manipulación, un acápite referido a la «Peligrosidad y Medidas de Seguridad». El programa de capacitación desarrollado permitió proveer conocimientos específicos referidos a esta temática. Conclusión: las medidas adoptadas en el laboratorio permiten plantear que de manera general se cumplen los requisitos establecidos en materia de Bioseguridad para el trabajo con microorganismos.Introduction: working with microorganisms can lead to risks for both the staff at work and the environment. The existence of biosafety labs and implementation of measures in the handling of biological agents minimize the risk. Objetive: to evaluate biosecurity measures taken in handling biological materials at Liorad Laboratories. Methods: using a checklist and analysis of results through a SWOT Matrix to assess whether the

Derivation of the formalism for neutrino matter oscillations from the neutrino relativistic field equations

International Nuclear Information System (INIS)

Mannheim, P.D.

1988-01-01

We derive the standard formalism of Mikheyev, Smirnov, and Wolfenstein for the oscillation of neutrinos in matter taking into account the Lorentz and second-quantized structure of the neutrino fields. We consider neutrinos with Dirac or Majorana masses

Neutrino mass from Cosmology

CERN Document Server

Lesgourgues, Julien

2012-01-01

Neutrinos can play an important role in the evolution of the Universe, modifying some of the cosmological observables. In this contribution we summarize the main aspects of cosmological relic neutrinos and we describe how the precision of present cosmological data can be used to learn about neutrino properties, in particular their mass, providing complementary information to beta decay and neutrinoless double-beta decay experiments. We show how the analysis of current cosmological observations, such as the anisotropies of the cosmic microwave background or the distribution of large-scale structure, provides an upper bound on the sum of neutrino masses of order 1 eV or less, with very good perspectives from future cosmological measurements which are expected to be sensitive to neutrino masses well into the sub-eV range.

17th International Workshop on Neutrino Factories and Future Neutrino Facilities Search

CERN Document Server