Precise nondivergent analytic formulas for the radiative corrections to the beta energy spectrum in hyperon semileptonic decays over the entire Dalitz plot

Very accurate analytical expressions for the radiative corrections of unpolarized hyperons semileptonic decays of charged and neutral baryons have been obtained in the recent past. Some of these formulas contain logarithmic singularities at the edges of the Dalitz plot for the three- and four-body decays. These singularities are analyzed and integrated analytically to obtain new divergentless formulas for the energy spectrum of the produced beta particle. The new equations contain terms of the order alpha times the momentum transfer, are applicable to any beta decay process and are suitable for a model-independent experimental analysis.Comment: 22 pages, 4 figure

Precise bounds on the Higgs boson mass

We study the renormalization group evolution of the Higgs quartic coupling $\lambda_{H}$ and the Higgs mass $m_{H}$ in the Standard Model. The one loop equation for $\lambda_{H}$ is non linear and it is of the Riccati type which we numerically and analytically solve in the energy range $[m_{t},E_{GU}]$ where $m_{t}$ is the mass of the top quark and $E_{GU}=10^{14}$ GeV. We find that depending on the value of $\lambda_{H}(m_{t})$ the solution for $\lambda_{H}(E)$ may have singularities or zeros and become negative in the former energy range so the ultra violet cut off of the standard model should be below the energy where the zero or singularity of $\lambda_{H}$ occurs. We find that for $0.369\leq\lambda_{H}(m_{t})\leq0.613$ the Standard Model is valid in the whole range $[m_{t},E_{GU}]$. We consider two cases of the Higgs mass relation to the parameters of the standard model: (a) the effective potential method and (b) the tree level mass relations. The limits for $\lambda_{H}(m_{t})$ correspond to the following Higgs mass relation $150\leq m_{H}\lessapprox 193$ GeV. We also plot the dependence of the ultra violet cut off on the value of the Higgs mass. We analyze the evolution of the vacuum expectation value of the Higgs field and show that it depends on the value of the Higgs mass. The pattern of the energy behavior of the VEV is different for the cases (a) and (b). The behavior of $\lambda_{H}(E)$, $m_{H}(E)$ and $v(E)$ indicates the existence of a phase transition in the standard model. For the effective potential this phase transition occurs at the mass range $m_{H}\approx 180$ GeV and for the tree level mass relations at $m_{H}\approx 168$ GeV.Comment: 14 pages, 7 figures. Expanded the discussion of the Higgs mass relation between the parameters of the Standard Model. Included the method of the Higgs effective potentia

La formación del clero diocesano durante la persecución religiosa en México 1910-1940. [Reseña]

Reseña de: Carlos Francisco VERA SOTO, La formación del clero diocesano durante la persecución religiosa en México 1910-1940, Departamento de publicaciones de la Universidad Pontificia de México («Biblioteca mexicana» 18), México 2005, 1446 pp

Evaluación del crecimiento de langostino blanco Litopenaeus vannamei cultivado en jaulas flotantes en la laguna Ñapique, distrito de San Cristo, Sechura-Piura

Se ha identificado en la zonas aledañas a la laguna Ñapique,la escasez de oportunidades de desarrollo de actividades económicas y rentables para los pobladores de Cerritos, Cristo NosValga, Onza de Oro, Santa Clara, Alto Huaraz, Chutuque, Laguna de San Ramón, Valverde, y MalaVida, quienes se dedican a actividades agropecuarias primarias la que absorbe una gran masas de la población económicamente activa, con un rendimiento promedio por debajo del promedio departamental de Piura cuenta con dos grandes reservorios e innumerables cuerpos de agua como lagunas y reservorios pequeños que utilizan los agricultores para sus actividades agrícolas, los mismo que presentan condiciones ecológicas favorables para la explotación acuícola de los recursos hidrobiológicos. La Dirección Regional de Pesquería considera potencialmente valido el desarrollo de la acuicultura en estos ambientes y dentro de los lineamientos de la política actual promueven el desarrollo de la acuicultura para lograr uno de los principales objetivos: vencer la pobreza y la desnutrición (ley No 27460 y reglamento, 2001). Una oportunidad para incrementar y desarrollar la economía de la zona es la actividad acuícola aprovechando la laguna Ñapique mediante el cultivo de langostino blanco Litopenaeus vananmei,en jaulas flotantes, integrado a actividades como la pesca artesanal y turismo. El impacto de dicha actividad generaría un efecto multiplicador a nivel regional sobre todo en los diferentes reservorios de agua del valle de San Lorenzo que se aproximan a las 200 ha y directamente beneficiaría a los 14.455 pobladores del distrito de Cristo Nos Valga, con la creación de puestos de trabajo, incremento de la producción pesquera, disminuir el índice de desnutrición y el índice de extrema pobreza. El objetivo principal fue evaluar el crecimiento durante todo el cultivo del langostino blanco Litopenaeus vananmei en jaulas flotantes, aprovechando el cuerpo de agua laguna Ñapique de manera ecológicamente sostenible, evaluando la densidad optima en la fase de precría y engorde, las tasa de crecimiento, rendimiento en biomasa, supervivencia y factor de conversión alimenticia

Radiative corrections to the Dalitz plot of K_{l3}^\pm decays

We calculate the model-independent radiative corrections to the Dalitz plot of K_{l3}^\pm decays to order (\alpha/\pi)(q/M_1), where q is the momentum transfer and M_1 is the mass of the kaon. The final results are presented, first, with the triple integration over the variables of the bremsstrahlung photon ready to be performed numerically and, second, in an analytical form. These two forms are useful to crosscheck on one another and with other calculations. This paper is organized to make it accessible and reliable in the analysis of the Dalitz plot of precision experiments and is not compromised to fixing the form factors at predetermined values. It is assumed that the real photons are kinematically discriminated. Otherwise, our results have a general model-independent applicability.Comment: RevTex4, 38 pages, 5 figures, 5 tables; some typos corrected; discussion extended to compare with other result

Synthesis, structure and reactivity of Pd and Ir complexes based on new lutidine-derived NHC/phosphine mixed pincer ligands

Coordination studies of new lutidine-derived hybrid NHC/phosphine ligands (CNP) to Pd and Ir have been performed. Treatment of the square-planar [Pd(CNP)Cl](AgCl2) complex 2a with KHMDS produces the selective deprotonation at the CH2P arm of the pincer to yield the pyridine-dearomatised complex 3a. A series of cationic [Ir(CNP)(cod)]+ complexes 4 has been prepared by reaction of the imidazolium salts 1 with Ir(acac)(cod). These derivatives exhibit in the solid state, and in solution, a distorted trigonal bipyramidal structure in which the CNP ligands adopt an unusual C(axial)–N(equatorial)–P(equatorial) coordination mode. Reactions of complexes 4 with CO and H2 yield the carbonyl species 5a(Cl) and 6a(Cl), and the dihydrido derivatives 7, respectively. Furthermore, upon reaction of complex 4b(Br) with base, selective deprotonation at the methylene CH2P arms is observed. The, thus formed, deprotonated Ir complex 8b reacts with H2 in a ligand-assisted process leading to the trihydrido complex 9b, which can also be obtained by reaction of 7b(Cl) with H2 in the presence of KOtBu. Finally, the catalytic activity of Ir–CNP complexes in the hydrogenation of ketones has been briefly assessed.CTQ2013-45011-P, CTQ2016-80814-R and CTQ2014 -51912-RE