3,360 research outputs found

    The onset of the solar active cycle 22

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    There is a great deal of interest in being able to predict the main characteristics of a solar activity cycle (SAC). One would like to know, for instance, how large the amplitude (R sub m) of a cycle is likely to be, i.e., the annual mean of the sunspot numbers at the maximum of SAC. Also, how long a cycle is likely to last, i.e., its period. It would also be interesting to be able to predict the details, like how steep the ascending phase of a cycle is likely to be. Questions like these are of practical importance to NASA in planning the launch schedule for the low altitude, expensive spacecrafts like the Hubble Space Telescope, the Space Station, etc. Also, one has to choose a proper orbit, so that once launched the threat of an atmospheric drag on the spacecraft is properly taken into account. Cosmic ray data seem to indicate that solar activity cycle 22 will surpass SAC 21 in activity. The value of R sub m for SAC 22 may approach that of SAC 19. It would be interesting to see whether this prediction is borne out. Researchers are greatly encouraged to proceed with the development of a comprehensive prediction model which includes information provided by cosmic ray data

    Reducing poverty and hunger in India: the role of agriculture

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    "India's strategy for reducing poverty and hunger has always placed a great deal of importance on the agricultural sector, reflecting the fact that 70 percent of the population lives in rural areas and the overwhelming majority of them depend upon agriculture as their primary source of income. The focus of attention has of course changed over time." from Textindia, Asia, Poverty reduction, Hunger, agricultural sector, rural areas, Irrigation, Water Management, Seeds, Agricultural productivity, Fertilizers, Agricultural diversification Economic aspects, Public investment,

    Front Form Spinors in Weinberg-Soper Formalism and Melosh Transformations for any Spin

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    Using the Weinberg-Soper formalism we construct the front form (j,0)⊕(0,j)(j,0)\oplus(0,j) spinors. Explicit expressions for the generalised Melosh transformations up to spin two are obtained. The formalism, without explicitly invoking any wave equations, reproduces spin one half front-form results of Melosh, Lepage and Brodsky, and Dziembowski.Comment: 16 Pages, RevTex. We continue to receive reprint requests for this paper. So we now archive it her

    Upper cut-off rigidity for corotation anisotropy during solar activity cycles 20 and 21

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    At the Eleventh International Conference on Cosmic Rays in 1969, the results of a study of the solar diurnal variations of solar rays observed during the ascending phase of solar activity cycle twenty was discussed. The diurnal variation, observed underground during 1965-68 period, and results from an extraterrestrial anisotropy having a continuously increasing upper cut-off rigidity R sub c were reported. However, the coupling functions applicable to underground telescopes were controversial then. This situation has improved now. Those results wsere re-examined and extended to cover the period 1965-78. The coupling functions given by Murakami et al. for underground muons and those given by Lockwood and Weber for neutron monitors were used showed that a great deal of care should be exercised in the value of R sub c was calculated. Although numerical values of R sub c are a little different, the trend for 1965-68 period remains unchanged. Highest value of R sub c occur in 1970 and the lowest value occurs in 1976

    Solar wind velocity and daily variation of cosmic rays

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    Recently parameters applicable to the solar wind and the interplanetary magnetic field (IMF) have become much better defined. Superior quality of data bases that are now available, particularly for post-1971 period, make it possible to believe the long-term trends in the data. These data are correlated with the secular changes observed in the diurnal variation parameters obtained from neutron monitor data at Deep River and underground muon telescope data at Embudo (30 MEW) and Socorro (82 MWE). The annual mean amplitudes appear to have large values during the epochs of high speed solar wind streams. Results are discussed

    Diurnal anisotropy during solar activity cycle twenty and diffusion-convection model

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    Underground muon telescope data obtained at Embudo and Neutron monitor data obtained at Deep River are divided into two sets; one covers the ascending phase of the cycle (1965-70) and the other covers the descending phase (1971-76). The amplitude of diurnal anisotropy calculated from the data does not agree with the value predicted by the simplified version of the Diffusion-Convection Model (DCM); the discrepancy is worse for neutron data

    Distribution des revenus et développement : quelques faits stylisés

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    In recent years, the relationship between income distribution and the process of development has come under increasing scrutinity. Much of the debate has focused on the hypothesis, originally advanced by Simon Kuznets, that the secular behavior of inequality follows an inverted U shaped pattern which inequality first increasing and then decreasing with development. This hypothesis has become so much a part of the conventional wisdom on this subject that it has generated considerable skepticism about the welfare implications of the development process. Indeed, on some interpretations, developing countries face the grim prospect not just of increasing relative inequality, but also of declining absolute incomes for the lower income groups.The object of the article is to re-examine the empirical basis for this hypothesis using a recent compilation of cross-country data made at the World Bank. The author uses multiple regression to estimate cross country relationships between inequality, as reflected in the income shares of various percentile groups, and selected explanatory variables reflecting different aspects of the development process. The results suggest that while there may be a secular time path for inequality which developing countries must traverse and which contains a phase of increasing inequality, there is at least no evidence that faster growing countries show higher inequality at the same level of development than slower growing countries

    Neutrino oscillations with disentanglement of a neutrino from its partners

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    We bring attention to the fact that in order to understand existing data on neutrino oscillations, and to design future experiments, it is imperative to appreciate the role of quantum entanglement. Once this is accounted for, the resulting energy-momentum conserving phenomenology requires a single new parameter related to disentanglement of a neutrino from its partners. This parameter may not be CP symmetric. We illustrate the new ideas, with potentially measurable effects, in the context of a novel experiment recently proposed by Gavrin, Gorbachev, Veretenkin, and Cleveland. The strongest impact of our ideas is on the resolution of various anomalies in neutrino oscillations and on neutrino propagation in astrophysical environments.Comment: 6 page
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