Reflectance measurements are used t o calculate the ordinary and extraordinary optical constants of an anisotropic MgFz crystal in the energy range 11 to 28 eV. Partially linearly polarized light is used and a method of least squares is employed to compute the results.An excitonic splitting of 0.5 eV is observed at the r point. The anisotropy of the forbidden gap is 0.2 eV while that of plasmon is 0.3 eV. A tentative interpretation is given based upon a symmetry group analysis a t the r point.Reflexionsmessungen werden zur Berechnung der ordentlichen und auBerordentlichen optischen Konstanten eines anisotropen MgF,-Kristalls im Energiebereich von 11 bis 28 eV benutet. Es wird tcilweise linear-polarisiertes Licht verwendet und eine Methode der kleinsten Quadrate zur Berechnung der Ergebnisse herangezogen. Am r -P u n k t wird eine exzitonische Aufspaltung von 0,5 eV beobachtet. Die Anisotropie der verbotenen Zone betragt 0,2 eV wahrend die des Plasmons 0,3 eV betragt. Es wird eine mogliche Erklarung angegeben, die auf einer Symmetriegruppenanalyqe am I'-Punkt beruht.

Neutron emission from a 3 KJ Mather-type plasma focus is studied. Specifically, the behavior of system with the change in anode length is investigated. Anode lengths of high and low fluence anisotropy as well as for high neutron yield are identified. Experiment also suggests the possibility of ion beam generation leading to neutron production via beam-plasma interaction.

There are many factors of methodological origin that influence the measurement of optical properties of the entire circulatory system which consists of blood as the basic component. The basic idea of this review article is to provide the optical properties of the circulatory system with all those factors of influence that have been employed in biomedical optics for different applications. We begin with the available optical properties, i.e., absorption, scattering and, reduced scattering coefficient, in general for any tissue inside the human body and prominent scattering theories (e.g., light, X-rays, neutrons) that are helpful in this regard. We have reviewed and compiled already available formulas and their respective available data for different human tissues for these optical properties. Then we have descended to the blood composition and to different scattering techniques available in the literature to study scattering and light propagation inside blood. We have reviewed both computational and theoretical scattering techniques.

We studied a Spherically Radially Anisotropic (SRA) multilayer sphere with an arbitrary number of layers. Within each layer permittivity components are different from each other in radial and tangential directions. Under the quasi-static approximation, we developed a more generalized mathematical model that can be used to calculate polarizability of the SRA multilayer sphere with any arbitrary number of layers. Moreover, the functionality of the SRA multilayer sphere as a cloak has been investigated. It has been shown that by choosing a suitable contrast between components of the permittivity, the SRA multilayer sphere can achieve threshold required for invisibility cloaking.

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