Title page for 91229011


[Back to Results | New Search]

Student Number 91229011
Author Wen-Hao Yeh(廨)
Author's Email Address s1229011@cc.ncu.edu.tw
Statistics This thesis had been viewed 1705 times. Download 218 times.
Department Graduate Institute of Astronomy
Year 2004
Semester 2
Degree Master
Type of Document Master's Thesis
Language English
Title Numerical Simulations of Binary Accretion Disks
Date of Defense 2005-07-06
Page Count 64
Keyword
  • accretion disk
  • Abstract After 1980s, the instabilities of accretion discs in dwarf novae interest both theoreticians and observers very much.
    The evolutin of stars in binary systems would affect the light curves. In cataclysmic variables (CVs), especially SU UMa type stars, the change of its luminosity is completely determined by the accretion disc around the primary star, i.e. the white dwarf.
    The secondary star leaves the main sequence and expands its photosphere to touch the Roche-lobe. Its mass transfers through the Lagrange point and goes into the primary's Roche-lobe. Due to the conservation of angular momentum, the mass goes around primary and form and accretion disc.
    We follow the parameters of ER UMa stars to study the formation, precession, and hot spot of accretion discs and produce the possible light curves for two different models.
    Table of Content 1 Introduction.........................................................1
    1.1 Characteristic of Dwarf Novae lightcurve.............................1
    1.2 Structure of Dwarf Novae.............................................2
    2 Numerical Methods....................................................4
    2.1 The Gravitational Force..............................................4
    2.2 Hydrodynamics........................................................6
    2.3 SPH..................................................................7
    2.4 Runge-Kutta Method..................................................9
    3 Numerical Tests.....................................................10
    3.1 The Test of Gravity.................................................10
    3.2 The Test of Viscosity...............................................10
    3.2.1Initial Particle Distribution.......................................12
    3.2.2The Results.........................................................14
    3.3 The Test of Periodicity Analysis....................................16
    4 Simulations of ER UMa stars.........................................19
    4.1 Initial Condition...................................................19
    4.1.1Initial Condition...................................................19
    4.1.2Mass Transfer.......................................................19
    4.1.3The Live Particles..................................................21
    4.1.4Simulations of Outburst.............................................22
    4.2 Simulation Result...................................................23
    4.2.1The Disc Formation..................................................25
    4.2.2The Disc Precession.................................................28
    4.2.3The Hot Spot........................................................28
    4.2.4Lightcurves.........................................................28
    5 Data Analysis.......................................................42
    5.1 Periodicity Analysis of Whole Data..................................42
    5.1.1ER UMa..............................................................42
    5.1.2RZ LMi..............................................................43
    5.2 Periodicity Analysis of Detail Data.................................43
    5.2.1ER UMa..............................................................47
    5.2.2RZ LMi..............................................................47
    6 Conclusion and Futer Work...........................................62
    6.1 Conclusion..........................................................62
    6.2 Future Work.........................................................62
    Bibliography.................................................64
    Reference Bath, G. T. 1973, Nature phys. Sci., 246, 84
    Osaki, Y. 1974, PASJ, 26, 429
    Pringle, J. E. 1981, ARAA, 19, 137
    Monaghan, J. J. 1985, Com. Phy. Rep., 3, 71
    Whitehurst, R. 1988a, MNRS, 232, 35
    Whitehurst, R. 1988b, MNRS, 233, 529
    Riffert, H., Herold, H., Flebbe, O., Ruder, H. 1995, Com. Phy. Com., 81, 1
    Press, W. H. et al, 1992, ``{sl Numerical Recipes in Fortran}' 2nd (Cambridge University Press)
    Kato, T., Kunjaya, C. 1995, PASJ, 47, 163
    Osaki, Y. 1996, PASJ, 108, 39
    Murray, C. D., Dermott, S. F. 1999, ``{it Solar System Dynamics}' (Cambridge University Press)
    Gao, W., Li, Z., Wu, X., Zhang, Z., Li, Y. 1999, ApJ, 527, L55
    Frank, J., King, A., Raine, D., 2002, ``{it Accretion Power in Astrophysics}' 3rd (Cambridge University Press)
    Advisor
  • Ing-Guey Jiang(Q)
  • Files
  • 91229011.pdf
  • approve in 2 years
    Date of Submission 2005-07-21

    [Back to Results | New Search]


    Browse | Search All Available ETDs

    If you have dissertation-related questions, please contact with the NCU library extension service section.
    Our service phone is (03)422-7151 Ext. 57407,E-mail is also welcomed.