red magnitude
2.Accurate stellar trigonometric parallaxes may provide reliable data for studies on the physical properties and evolutional status of stars such as white dwarfs, red dwarfs, O and B stars, Herbig Ae and Be stars, and Ap and Am stars. Some fundamental parameters like absolute magnitude, effective temperature and radii of these stars and their positions in the HR diagram are of great importance in astronomical researches.
3.The investigation shows that appropriate magnitude of red-shifting should be put on the incident light in order to produce bistable properties for focusing nonlinear medium (χ(3)>0),and blue-shifting for defocusing nonlinear medium (χ(3)<0).
