No abstract

The paper is almost entirely mathematical, and calculates the effect on the visibility of an object, illuminated by a projector, of the scattering and absorption of the light by the atmosphere. The discussion is divided into three parts dealing separately with the light reflected from the object from the incident beam, with the brightness of the atmospheric background due to scattered light, and of the conditions of visibility as functions of the two previous quantities. Numerical solutions of the equations are given and range curves are drawn for objects of different sizes and different reflecting powers and for sources of varying intensity.

No abstract

No abstract

Phase transitions manifest themselves as strong softening in the equation of state. That influence on the collapse dynamics of neutron stars and stellar cores is considered. The transition of a neutron star to a pion-condensed star can be accompanied by an ejection of a small mass fraction for certain ultradense equations of state. The collapse outcome of stellar cores is not influenced by a phase transition in nuclear matter below nuclear density.