Temperature-averaged and total free-free Gaunt factors for κ and Maxwellian distributions of electrons

Aims. Optically thin plasmas may deviate from thermal equilibrium and thus, electrons (and ions) are no longer described by the Maxwellian distribution. Instead they can be described by κ-distributions. The free-free spectrum and radiative losses depend on the temperature-averaged (over the electrons distribution) and total Gaunt factors, respectively. Thus, there is a need to calculate and make available these factors to be used by any software that deals with plasma emission. Methods. We recalculated the free-free Gaunt factor for a wide range of energies and frequencies using hypergeometric functions of complex arguments and the Clenshaw recurrence formula technique combined with approximations whenever the difference between the initial and final electron energies is smaller than 10−10 in units of z2Ry. We used double and quadruple precisions. The temperature- averaged and total Gaunt factors calculations make use of the Gauss-Laguerre integration with 128 nodes. Results. The temperature-averaged and total Gaunt factors depend on the κ parameter, which shows increasing deviations (with respect to the results obtained with the use of the Maxwellian distribution) with decreasing κ. Tables of these Gaunt factors are provided.

Validación del software educativo Poliestudio 1.0: informe de investigación

PoliEstudio 1.0 is a computational tool, with free license, created to work with polynomial expressions in one variable and it was created by a team in which the authors of this article are part of. This article documents the qualitative validation performed to this software which main objective was to bring to the Costa Rican Educational System a validated educational software that can solve, partially, the problems that nowadays exists in the mathematic education of secondary students, particularly in the topics related to polynomial expressions in one variable and specifically to those students who are in eighth grade.

LA MAPOTECA VIRTUAL: UN EJEMPLO DE COLABORACIÓN BAJO UNA PLATAFORMA DE SOFTWARE LIBRE

La Mapoteca Virtual es un sitio web construido sobre la plataforma Joomla, auspiciado por la Escuela de Ciencias Geográfica de la Universidad Nacional, en colaboración con UNA VIRTUAL.Este sitio pretende apoyar la labor docente al permitirle cargar y difundir cartografía digital para los estudiantes, y a los investigadores les facilita la localización de cartografía en línea, necesaria para la realización de sus trabajos en diferentes áreas del conocimiento. Adicionalmente, es un espacio para presentar documentos actuales en relación a la práctica de la cartografía y ciencias conexas, a la vez que fomenta la colaboración y el acceso libre a cartografía digital.Palabras clave: Cartografía, Joomla, Mapas digitales, Herramientas didácticas en líneaAbstractThe Virtual Map Library, www.mapoteca.geo.una.ac.cr, is a website constructed on the Joomla platform and supported by the School of Geographic Sciences at National University, Costa Rica, in collaboration with UNAVIRTUAL. The site intends to support the work of education by allowing the teacher to load and disseminate digital cartography for the students and helping geographic investigators locate cartography needed to accomplish their works in different areas of knowledge.In addition, Mapoteca offers a space to present current  documents relating to the practice of cartography and related sciences that at the same time promotes the contribution and free access to digital cartography.Key Words: Cartography, Mapoteca Virtual, Virtual Map Library, Joomla, digital maps, online teaching tools, School of Geographic Sciences, National University, Costa Rica.