中文摘要
行星和微粒子動態系統用來研究岩屑盤的分布密度。本文中，我們主要是探討beta參數對HR8799的岩屑盤動態系統的影響。假設內盤的粒子因運行過程中產生碰撞而爆炸變成許多更小的微粒子，並且受到地心引力與輻射的影響，使得粒子向外移動形成外盤。最後我們利用電腦使用不同的模型模擬各種結果。

Abstract
The planets and grains' dynamical models are employed to study the density distribution of debris disc. In this thesis, we investigate the effects of beta, where beta is the value of the ratio between the radiation pressure force and the gravitational, to simulate the HR8799's disc. We set the particles, in the inner disc, would be collided with each other and be broken into many dust grains when them move. Those dust grains would be blown out, over a long period of time, then they would form the starts disc. Finally, we use different models to simulate the results.

CONTENTS
1.Introduction------------------------------------1
2.Three Planets and A Dust Grain------------------4
3.Simulations for The Initial Circular Motion of Three Planets-------------------------------------------8
4.Simulation of Model-----------------------------25
5.Conclusion--------------------------------------41
6.Bibliography------------------------------------42
7.Appendix----------------------------------------43

Bibliography
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106, 1993, 102
[2] Fabrycky, D.C. and Murray-Clay, R.A., Multiplanet System HR8799, the Astrophysical Journal, 710:1408-1421, 2010 February 20
[3] Marois, C. et al, Direct Imaging of Multiple Planets Orbiting the Star HR8799, Science, 322, 2008
[4] Murray, C.D and Dermott, S.F., Solar System Dynamics, Cambridge University Press, 2001
[5] Su, K.Y.L. et al, The Debris Disk Around HR8799, the Astrophysical Journal, 705:314-327, 2009 November 1