5 research outputs found
Enhanced Joule Heating in Umbral Dots
We present a study of magnetic profiles of umbral dots (UDs) and its
consequences on the Joule heating mechanisms. Hamedivafa (2003) studied Joule
heating using vertical component of magnetic field. In this paper UDs magnetic
profile has been investigated including the new azimuthal component of magnetic
field which might explain the relatively larger enhancement of Joule heating
causing more brightness near circumference of UD.Comment: 8 pages, 1 figure, accepted in Solar Physic
A ‘VISUAL’ APPROACH TO MENANDER - (A.K.) Petrides Menander, New Comedy and the Visual. Pp. xii + 322, ills. Cambridge: Cambridge University Press, 2014. Cased, £65, US$99. ISBN: 978-1-107-06843-8.
High-energy X-rays and gamma-rays from solar flares were discovered just over
fifty years ago. Since that time, the standard for the interpretation of
spatially integrated flare X-ray spectra at energies above several tens of keV
has been the collisional thick-target model. After the launch of the Reuven
Ramaty High Energy Solar Spectroscopic Imager (RHESSI) in early 2002, X-ray
spectra and images have been of sufficient quality to allow a greater focus on
the energetic electrons responsible for the X-ray emission, including their
origin and their interactions with the flare plasma and magnetic field. The
result has been new insights into the flaring process, as well as more
quantitative models for both electron acceleration and propagation, and for the
flare environment with which the electrons interact. In this article we review
our current understanding of electron acceleration, energy loss, and
propagation in flares. Implications of these new results for the collisional
thick-target model, for general flare models, and for future flare studies are
discussed.Comment: This is an article from a monograph on the physics of solar flares,
inspired by RHESSI observations. The individual articles are to appear in
Space Science Reviews (2011
Institutional adaptation: Demands for management reform and university administration
Higher education organizations around the world have always faced environmental changes. However, in the past decade altered societal expectations, new public policies, and technological innovations have created an unprecedented set of challenges for universities. Although the borders of universities have opened in new ways for thei