Charged lepton Flavor Violation in Supersymmetry with Bilinear R-Parity Violation

The simplest unified extension of the Minimal Supersymmetric Standard Model with bi-linear R-parity violation naturally predicts a hierarchical neutrino mass spectrum, suitable to explain atmospheric and solar neutrino fluxes. We study whether the individual violation of the lepton numbers L_{e,mu,tau} in the charged sector can lead to measurable rates for BR(mu->e gamma)and $BR(tau-> mu gamma). We find that some of the R-parity violating terms that are compatible with the observed atmospheric neutrino oscillations could lead to rates for mu->e gamma measurable in projected experiments. However, the Delta m^2_{12} obtained for those parameters is too high to be compatible with the solar neutrino data, excluding therefore the possibility of having measurable rates for mu->e gamma in the model.Comment: 29 pages, 8 figures. Constraint from solar neutrino data included, conclusions changed respect v

Magnetocaloric Effect In The Rni5 (r = Pr, Nd, Gd, Tb, Dy, Ho, Er) Series

In this paper, the magnetocaloric effect in the hexagonal intermetallic compounds belonging to the RNi5 series was calculated using a Hamiltonian including the crystalline electrical field, exchange interaction, and the Zeeman effect. Experimental work was performed and the two thermodynamics quantities, namely, isothermal entropy change and adiabatic temperature change were obtained for polycrystalline samples using heat capacity measurements, and compared to the theoretical predictions.70131344281-134428-6Pecharsky, V.K., Gschneidner Jr., K.A., (1997) Phys. Rev. Lett., 78, p. 4494Gschneidner Jr., K.A., Pecharsky, V.K., (1997) Rare Earths: Science, Technology and Application III, , edited by R. C. Bautista, C. O. Bounds, T. W. Ellis, and B. T. Kilbourn (The Minerals, Metals and Materials Society, Warendale, PATegus, O., Bruck, E., Buschow, K.H.J., De Boer, F.R., (2002) Nature (London), 415, p. 150Wada, H., Tanabe, Y., (2001) Appl. Phys. Lett., 79, p. 20(2001) Appl. Phys. Lett., 79, p. 3302Wada, H., Morikawa, T., Taniguchi, K., Shibata, T., Yamada, Y., Akishige, Y., (2003) Physica B, 328, p. 114Von Ranke, P.J., De Oliveira, N.A., Gama, S., (2004) J. Magn. Magn. Mater., 277, p. 78Von Ranke, P.J., De Campos, A., Caron, L., Coelho, A.A., Gama, S., De Oliveira, N.A., unpublishedVon Ranke, P.J., De Oliveira, N.A., Gama, S., (2004) Phys. Lett. A, 320, p. 302Von Ranke, P.J., Lima, A.L., Nóbrega, E.P., Da Silva, X., Guimarães, A.P., Oliveira, I.S., (2001) Phys. Rev. B, 63, p. 024422Von Ranke, P.J., Pecharsky, V.K., Gschneidner, K.A., Korte, B.J., (1998) Phys. Rev. B, 58, p. 14436Buschow, K.H.J., Van Der Goot, A.S., (1971) Acta Crystallogr., Sect. B: Struct. Crystallogr. Cryst. Chem., 27, p. 1085Stevens, K.W.H., (1952) Proc. Phys. Soc., London, Sect. A, 65, p. 209Radwanski, R.J., Kim-Ngan, N.H., Kayzel, F.E., Franse, J.J.M., Gignoux, D., Schmitt, D., Zhang, F.Y., (1992) J. Phys.: Condens. Matter, 4, p. 8853Tishin, A.M., Magnetocaloric effect in the vicinity of phase transitions (1999) Handbook of Magnetic Materials, 12, pp. 395-524. , edited by K. H. J. Buschow (North-Holland Elsevier, Amsterdam, the Netherlands), Chap. 4Marzouk, N., Graig, R.S., Wallace, W.E., (1973) J. Phys. Chem. Solids, 34, p. 15Barthem, V.M.T.S., Gignoux, D., Schmitt, D., (1989) J. Magn. Magn. Mater., 78, p. 56Zhang, F.Y., Gignoux, D., Schmitt, D., Franse, J.J.M., Kayzel, F.E., Kim-Ngan, N.H., Radwanski, R.J., (1994) J. Magn. Magn. Mater., 130, p. 108Morellon, L., Algarabel, P.A., Ibarra, M.R., Del Moral, A., Gignoux, D., Schmitt, D., (1996) J. Magn. Magn. Mater., 153, p. 17Barthem, V.M.T.S., Gignoux, D., Nait-Saada, A., Schmitt, D., Takeuchi, A.Y., (1989) J. Magn. Magn. Mater., 80, p. 142Gignoux, D., Givord, D., Del Moral, A., (1976) Solid State Commun., 19, p. 891Andreeff, A., Valter, V., Grissmann, H., Kaun, L.P., Lipold, B., Mats, V., Franzkhaim, T., (1978) JINR Rapid Commun., 1978, pp. 14-11324Marzouk, N., Graig, R.S., Wallace, W.E., (1973) J. Phys. Chem. Solids, 34, p. 1

Probing neutrino properties with charged scalar lepton decays

Supersymmetry with bilinear R-parity violation provides a predictive framework for neutrino masses and mixings in agreement with current neutrino oscillation data. The model leads to striking signals at future colliders through the R-parity violating decays of the lightest supersymmetric particle. Here we study charged scalar lepton decays and demonstrate that if the scalar tau is the LSP (i) it will decay within the detector, despite the smallness of the neutrino masses, (ii) the relative ratio of branching ratios Br({tilde tau}_1 --> e sum nu_i)/ Br({tilde tau}_1 --> mu sum nu_i) is predicted from the measured solar neutrino angle, and (iii) scalar muon and scalar electron decays will allow to test the consistency of the model. Thus, bilinear R-parity breaking SUSY will be testable at future colliders also in the case where the LSP is not the neutralino.Comment: 24 pages, 8 ps figs Report-no.: IFIC/02-33 and ZU-TH 11/0

Economic analysis of an agrosilvipastoral system for a mountainous area in Zona da Mata Mineira, Brazil

The objective of this work was to evaluate the economic viability of an agrosilvipastoral system developed for Zona da Mata mountainous areas in Minas Gerais state, Brazil, as well as to compare different options for wood (Eucalyptus grandis and Acacia mangium) commercialization of the second thinning. The data were obtained from a 10 year-old agrosilvipastoral system established in four hectares at Embrapa Gado de Leite station in Coronel Pacheco, MG, Brazil. As evaluation criteria for the economic viability analysis, the adopted methods were the net present value (NPV) and the internal rate of return (IRR), both calculated at 6% interest rate. Despite the small difference, adding value to forest products increased the attractiveness of the proposed system. Considered separately, the agricultural activity was impracticable, whereas the forestry and livestock activities were independently viable. The studied system seems to be equally tolerant to price variations for forest and livestock products, as well as strongly tolerant to variations in production costs

Adaptabilidade e estabilidade fenotípica de cultivares de café arábica em Minas Gerais

O objetivo deste trabalho foi avaliar a adaptabilidade e a estabilidade fenotípicas para a produtividade de cultivares de cafeeiro do grupo Catuaí, pela metododologia de Annicchiarico. Foram instalados e conduzidos experimentos em Três Pontas, Campos Altos e Capelinha, em Minas Gerais. O delineamento foi o de blocos ao acaso, com quatro repetições e seis plantas por parcela. Os tratamentos foram constituídos por 15 cultivares do grupo Catuaí e cinco testemunhas. As avaliações da produtividade foram realizadas em seis colheitas nas safras de 2003/2004 a 2008/2009. Posteriormente, foi realizada a análise conjunta dos três locais e a avaliação da adaptabilidade e da estabilidade das cultivares. Na safra 2008/2009, foi avaliado o percentual de frutos chochos e a percentagem de grãos em peneira alta. As cultivares Catuaí Vermelho IAC 15, Catuaí Amarelo IAC 30, Catuaí Amarelo IAC 62 e Catuaí Vermelho IAC 72 são mais promissoras, pois aliam maiores estabilidade e adaptabilidade em ambientes favoráveis e desfavoráveis com alta média de produtividade. As cultivares Catuaí Vermelho IAC 100, Catuaí Amarelo IAC 86, Rubi MG 1192 e Catuaí Vermelho IAC 144 têm o mais alto percentual de peneira alta. Todas as progênies têm baixo percentual de grãos chocho

Soil cover plants on water erosion control in the South of Minas Gerais

Water erosion is responsible for soil, water, carbon and nutrient losses, turning into the most important type of degradation of Brazilian soils. This study aimed to evaluate the influence of three cover plants under two tillage systems on water erosion control in an Argisol at south of Minas Gerais state, Brazil. The cover plants utilized in the study were pigeon pea, jack bean and millet, under contour seeding and downslope tillage. Experimental plots of 4 x 12 m, with 9% slope, under natural rainfall were used for the quantification of losses of soil, water, nutrients, and organic matter. One experimental plot was kept without plant cover (reference). Higher erosivity was observed in December and January, although a great quantity of erosive rainfall was detected during the whole raining period. Contour seeding provided a greater reduction of water erosion than downslope tillage, as expected. The jack bean under contour seeding revealed the lowest values of soil, water, nutrients and organic matter losses