Statistical Distribution Of Molecular Clouds For Star Formation In Galaxies

Abstract

In the struggle toward an understanding of the process of star formation it is one of the most important tasks to study the initial properties of the cold and dense interstellar medium. Stars are known to form in dense molecular clouds, but it is not yet fully understood how they from the neutral gas that permeates the Galaxies. Therefore, it is crucial to fully understand the creation process of molecular clouds. Colliding ows are a possible explanation for this process.For the Jeans mass and spiral structure we use virial theorem is used and this tell as the gravity must stronger than the kinetic energy ( the energy due to thermal pressure.)in order to the clouds collapse and forms prostar 3 2 GM R 2 3 2 M m KT .For a spherically symmetric system with a mass pro le M(r), neglecting pressure forces, we can calculate the time a freely falling mass shell at a radius R needs to fall to the center. By considering the conservation total energy the free time is derived (tff = ( 32 3G ) 1 2) By numerical models equations are governed considering initial and boundary condition of conservation laws for the mass, momentum, magnetic ux, and energy is solved in a cubic domain of linear size L with triply periodic boundary conditions , the log normal distribution of column densities, the mass-weighted distribution of thermal pressure, and relationship for molecular clouds.Finally,by considering Gaussian probability function of nding a particle in a given position spherical boundary condition can be solved the distribution of molecular clouds in the galaxies.