5,802 research outputs found

    Detection of Exotic Massive Hadrons in Ultra High Energy Cosmic Ray Telescopes

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    We investigate the detection of exotic massive strongly interacting hadrons (uhecrons) in ultra high energy cosmic ray telescopes. The conclusion is that experiments such as the Pierre Auger Observatory have the potential to detect these particles. It is shown that uhecron showers have clear distinctive features when compared to proton and nuclear showers. The simulation of uhecron air showers, and its detection and reconstruction by fluorescence telescopes is described. We determine basic cuts in observables that will separate uhecrons from the cosmic ray bulk, assuming this is composed by protons. If these are composed by heavier nucleus the separation will be much improved. We also discuss photon induced showers. The complementarity between uhecron detection in accelerator experiments is discussed.Comment: 9 page 9 figure

    Neutrino Telescopes' Sensitivity to Dark Matter

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    The nature of the dark matter of the Universe is yet unknown and most likely is connected with new physics. The search for its composition is under way through direct and indirect detection. Fundamental physical aspects such as energy threshold, geometry and location are taken into account to investigate proposed neutrino telescopes of km^3 volume sensitivities to dark matter. These sensitivities are just sufficient to test a few WIMP scenarios. Telescopes of km^3 volume, such as IceCube, can definitely discover or exclude superheavy (M > 10^10 GeV) Strong Interacting Massive Particles (Simpzillas). Smaller neutrino telescopes such as ANTARES, AMANDA-II and NESTOR can probe a large region of the Simpzilla parameter space.Comment: 28 pages, 9 figure

    Astrophysical Neutrino Event Rates and Sensitivity for Neutrino Telescopes

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    Spectacular processes in astrophysical sites produce high-energy cosmic rays which are further accelerated by Fermi-shocks into a power-law spectrum. These, in passing through radiation fields and matter, produce neutrinos. Neutrino telescopes are designed with large detection volumes to observe such astrophysical sources. A large volume is necessary because the fluxes and cross-sections are small. We estimate various telescopes' sensitivities and expected event rates from astrophysical sources of high-energy neutrinos. We find that an ideal detector of km^2 incident area can be sensitive to a flux of neutrinos integrated over energy from 10^5 and 10^{7} GeV as low as 1.3 * 10^(-8) * E^(-2) (GeV/cm^2 s sr) which is three times smaller than the Waxman-Bachall conservative upper limit on potential neutrino flux. A real detector will have degraded performance. Detection from known point sources is possible but unlikely unless there is prior knowledge of the source location and neutrino arrival time.Comment: Section added +modification

    Herramientas SIG para el analisis espacial de la vulnerabilidad de un acuifero

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    Só está disponível o resumo.Herramientas SIG para el analisis espacial de la vulnerabilidad de un acuifero

    Unconfined aquifer vulnerability related to topical pollution – Montes Torozos (Spain)

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    Este artigo deriva de uma comunicação apresentada em International workshop “Uranium, Environment and Public Health”In this paper it is shown the vulnerability model fitted to the unconfined aquifer of Montes Torozos (Spain). The most dangerous elements were taken under consideration (e.g. Hydrocarbons, explosives, radioactive materials). The identification of their source location and the transportation of dangerous goods across them has been the starting point of this study. The simulations took into consideration the connection between the capital of the province (Valladolid) to Villanubla airport and between Valladolid to the electrical transformer substation, located in the south-west edge of the hydrogeological unit of the Montes Torozos

    Absorção via foliar de aminoácidos em mudas de videira cv. Thompson seedless em cultivo hidropônico.

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    Este trabalho teve por objetivo quantificar o teor de N proveniente dos aminoácidos, absorvidos via foliar, em mudas de videira da cultivar Thompson Seedless

    Molecular diagnosis of Eimeria species affecting naturally infected Gallus gallus.

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    Abstract - We used PCR to test various protocols and define a technique for DNA extraction directly from chicken-shed stool samples for the identification of Eimeria species that parasitize birds. It was possible to extract and amplify DNA of seven Eimeria species from field stool samples, using both protocols tested; extractions made with phenol/chloroform protocols gave the best results. The primers were specific and sensitive, allowing amplification of samples containing as few as 20 oocysts, both in individual and in a multiplex PCR. Individualized PCR with the phenol/chloroform DNA extraction protocol detected a larger number of Eimeria species. Molecular diagnosis was found to be practical and precise, and can be used for monitoring and epidemiological studies of Eimeria

    Spatio-temporal vulnerability assessment in fractured groundwater systems

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    Governance reforms are required to demonstrate adaptive and resilient urban water resource management that considers complexity, uncertainty in immediate and long term change. Contamination of groundwater is a complex process and full of uncertainty at local and regional scale. The main objective of this research is the study of vulnerability to pollution in an unconfined karstic aquifer. Mainly it is addressed vulnerability integration, in relation to policy, specifically in risk evaluation and risk–benefit considerations. Development of an integrated vulnerability assessment methodology can be useful to effectively manage and protect this valuable freshwater source. The research insights suggest that the establishment of a pattern of effective governance is mandatory as the future highway, the prison and the airport are overlaying the most vulnerable areas of the aquifer and therefore provide policy makers guidance in overcoming urban water governance challenges.info:eu-repo/semantics/publishedVersio

    Hydrogeological vulnerability assessment in urban systems, Spain

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    Resumo alargado da comunicação oral apresentada na 6th International Conference on Environmental Science and Development.The main objective of this research is the study of vulnerability to pollution in an unconfined karstic aquifer system. Aquifer vulnerability assessment to define critical zones of contamination is a core issue an effective monitoring network for groundwater management. Vulnerability integration is addressed for risk valuation and risk–benefit considerations, focusing the requirements of the European Community’s Water and Groundwater Directives. The development of an integrated vulnerability assessment methodology can be useful for the effective management and protection of this valuable freshwater source. The research insights suggest that an effective governance is mandatory as the future highway, the prison and the airport are overlaying the aquifer’s most vulnerable areas
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