中文摘要：

该文介绍了一种用Monte Carlo法模拟Lyα谱线轮廓的代码．该代码以Verhamme的思想与方法为基础，结合了其它的模拟方法，通过几种模型，模拟出了多种情况下的Lyα谱线轮廓．文中详细说明了该代码的模拟方法并讨论了模拟出的结果．

英文摘要：

In this paper, a code of simulations of Lyα line profiles via Monte Carlo methods is introduced. This code is developed based on the ideas of Anne Verhamme, Daniel Schaefer and Antonella Maselli, combining with the methods of Matthew Hansen and S. Peng Oh. The simulation of one Lyα photon starts when the photon is created and ends when the photon escapes from the medium or is absorbed by the dust. The Lyα photon is created at the isotropic source, which can be monochromatic or non-monochromatic. After being created, the photon walks in the medium. It moves from one position, where it interacts with the medium, to the next, until it moves out of the medium or absorbed by the dust. The direction and the frequency of the photon will be changed after it interacts with the H atom. The photon has probability to interact with the dust, which may absorb or scatter the photon. When a simulation of one photon is completed, the photon will be recorded and the simulation of another photon begins. After all of the photons are simulated, the line profile will be calculated. In 2006, Verhamme, Schaerer and Maselli developed a general code for 3D Lyα radiation transfer in galaxies. As they did, in this paper, three kinds of model are used. The first one is slab, which is made by three infinite parallel planes. The middle one of the three planes is the source, and the other two are the edges, between which is the medium. Although this model is simple, many kinds of line profiles, such as symmetric double peaks, redshifted/blueshifted single peak and damped profile, can be obtained by changing the conditions of the source and the medium. The profile of the static dust free slab is similar with the analytic solutions of Neufeld （1990）. The second model is halo, which is a ball of medium. The source can be in the center of the ball or be spread in the medium. Symmetric double peaks, redshifted/blueshifted single peak and P-Cygni profile can be obtained by changing the conditions. The third one is the expanding shell, a she