8,203 research outputs found
Electroweak Tests at Beta-beams
We explore the possibility of measuring the Weinberg angle from
(anti)neutrino-electron scattering using low energy beta beams, a method that
produces single flavour neutrino beams from the beta-decay of boosted
radioactive ions. We study how the sensitivity of a possible measurement
depends on the intensity of the ion beam and on a combination of different
Lorentz boosts of the ions.Comment: 10 pages, 6 figure
Dark matter cores in the Fornax and Sculptor dwarf galaxies: joining halo assembly and detailed star formation histories
We combine the detailed Star Formation Histories of the Fornax and Sculptor
dwarf Spheroidals with the Mass Assembly History of their dark matter (DM) halo
progenitors to estimate if the energy deposited by Supernova type II (SNeII) is
sufficient to create a substantial DM core. Assuming the efficiency of energy
injection of the SNeII into DM particles is , we find
that a single early episode, , that combines the
energy of all SNeII due to explode over 0.5 Gyr, is sufficient to create a core
of several hundred parsecs in both Sculptor and Fornax. Therefore, our results
suggest that it is energetically plausible to form cores in Cold Dark Matter
(CDM) halos via early episodic gas outflows triggered by SNeII. Furthermore,
based on CDM merger rates and phase-space density considerations, we argue that
the probability of a subsequent complete regeneration of the cusp is small for
a substantial fraction of dwarf-size haloes.Comment: ApJL accepted versio
Influence of the external pressure on the quantum correlations of molecular magnets
The study of quantum correlations in solid state systems is a large avenue
for research and their detection and manipulation are an actual challenge to
overcome. In this context, we show by using first-principles calculations on
the prototype material KNaCuSiO that the degree of quantum
correlations in this spin cluster system can be managed by external hydrostatic
pressure. Our results open the doors for research in detection and manipulation
of quantum correlations in magnetic systems with promising applications in
quantum information science
Caracterização de acessos silvestres de maracujazeiro com base em descritores morfoagronômicos.
Existem espécies silvestres de maracujazeiros que possuem potencial agronômico para a utilização no melhoramento genético e no desenvolvimento de variedades e híbridos, porém a escassez de informações morfoagronômicas dessas espécies silvestres indica a necessidade de estudos básicos relacionados à caracterização e à avaliação do germoplasma. Este trabalho teve como objetivo caracterizar acessos silvestres de maracujazeiro, com base em descritores qualitativos e quantitativos
Correlação entre heterose e divergência genética em genótipos de maracujá amarelo.
Este trabalho avaliou a heterose de híbridos de maracujá amarelo, obtidos por cruzamentos dialélicos entre genótipos divergentes e a sua correlação com a distância genética obtida por meio de marcadores ISSR (Inter Simple Sequence Repeats). Os trinta híbridos resultantes do dialelo parcial apresentaram diferenças significativas para as variáveis: número de frutos (NF), peso do fruto (PF), produtividade (PROD), rendimento (REND) e sólidos solúveis totais (SST). Apenas a variável número de frutos apresentou efeitos aditivos no controle genético. Não foi observada correlação significativa pela estatística de Mantel entre distância genética vs heterose, capacidade específica de combinação e a média para as características analisadas, o que não permite predizer o comportamento dos híbridos de maracujazeiro
A Conserved Vector Current test using low energy beta-beams
We discuss the possibility of testing the weak currents and, in particular,
the weak magnetism term through the measurement of the electron anti-neutrinos
capture by protons at a low energy beta-beam facility. We analyze the
sensitivity using both the total number of events and the angular distribution
of the positrons emitted in a water Cerenkov detector. We show that the weak
magnetism form factor might be determined with better than several percent
accuracy using the angular distribution. This offers a new way of testing the
Conserved Vector Current hypothesis.Comment: 8 pages, 5 figure
Inseticidas e intervalos de pulverizacao para o controle lagarta rosada (Pectinophora gossypiela (Saund) (Lepidoptera, gelechiidae) no algodoeiro herbaceo.
bitstream/item/33358/1/INSETICIDAS-INTERVALOS.pd
Ultra-low-cycle fatigue of pipeline steels
PING 2019 is organized with the support of funds for specific university research project SVK1-2019-002.Pipelines and piping components when subjected to extreme loading conditions (e.g. earthquakes, hurricanes, support settlements, industrial plant shutdown) undergo large plastic deformations, associated with widespread yielding, leading to fracture, either due to monotonic loading or ultra-low-cycle fatigue (ULCF). ULCF is neither satisfactorily understood nor conveniently investigated compared to the monotonic ductile or low-cycle fatigue damage mechanisms. Having in mind the existing gaps in the knowledge about the ULCF, the ULCF European project, coordinated by FEUP, aimed at developing innovative computational methodologies for the simulation of steel material fracture under both monotonic and ultra-low-cycle fatigue, based on a significant experimental program including small and large-scale tests. This presentation makes an overview of the main results of the project, which includes: i) Database of small-scale testing data covering the X52, X60, X65, X70 and X80 piping steel grades. Smooth and special notched specimens were tested under both monotonic and cyclic (LCF & ULCF) loading. Dedicated monotonic tests were performed to assess the anisotropic behaviour of some materials (X70/X80). Combined multiaxial loading conditions were also investigated. ii) Database of full-scale testing results covering same materials also tested under small-scale conditions was generated. Monotonic and ULCF tests of pipe components were performed. ULCF tests included buckled and dented pipes, elbows and straight pipes. iii) New constitutive models for both monotonic and ULCF loading were proposed. Besides the Barcelona model, alternative approaches were investigated. Further constitutive refinements of nonlinear monotonic damage and enhanced anisotropic models, were also studied. iv) Developed constitutive models were calibrated and validated using experimentally derived testing data
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