Difference between revisions of "User:Tohline/Appendix/Ramblings/ForPaulFisher"
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==Overview of Dissertation== | |||
[https://digitalcommons.lsu.edu/gradschool_disstheses/6940/ Paul Fisher's (1999) doctoral dissertation] (accessible via the LSU Digital Commons) is titled, ''Nonaxisymmetric Equilibrium Models for Gaseous Galaxy Disks.'' Its abstract reads, in part: | [https://digitalcommons.lsu.edu/gradschool_disstheses/6940/ Paul Fisher's (1999) doctoral dissertation] (accessible via the LSU Digital Commons) is titled, ''Nonaxisymmetric Equilibrium Models for Gaseous Galaxy Disks.'' Its abstract reads, in part: | ||
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<font color="darkgreen">Three-dimensional hydrodynamic simulations show that, in the absence of self-gravity, an axisymmetric, gaseous galaxy disk whose angular momentum vector is initially tipped at an angle, <math>~i_0</math>, to the symmetry axis of a fixed spheroidal dark matter halo potential does not settle to the equatorial plane of the halo. Instead, the disk settles to a plane that is tipped at an angle, <math>~\alpha = \tan^{-1}[q^2 \tan i_0]</math>, to the equatorial plane of the halo, where <math>~q</math> is the axis ratio of the halo equipotential surfaces. The equilibrium configuration to which the disk settles appears to be flat but it exhibits distinct nonaxisymmetric features. .</font> | <font color="darkgreen">Three-dimensional hydrodynamic simulations show that, in the absence of self-gravity, an axisymmetric, gaseous galaxy disk whose angular momentum vector is initially tipped at an angle, <math>~i_0</math>, to the symmetry axis of a fixed spheroidal dark matter halo potential does not settle to the equatorial plane of the halo. Instead, the disk settles to a plane that is tipped at an angle, <math>~\alpha = \tan^{-1}[q^2 \tan i_0]</math>, to the equatorial plane of the halo, where <math>~q</math> is the axis ratio of the halo equipotential surfaces. The equilibrium configuration to which the disk settles appears to be flat but it exhibits distinct nonaxisymmetric features. .</font> | ||
</td></tr></table> | </td></tr></table> | ||
All three-dimensional hydrodynamic simulations employ Richstone's (1980) time-independent "axisymmetric logarithmic potential" that is prescribed by the expression, | |||
<table border="0" cellpadding="5" align="center"> | |||
<tr> | |||
<td align="right"> | |||
<math>~\Phi(x, y, z)</math> | |||
</td> | |||
<td align="center"> | |||
<math>~=</math> | |||
</td> | |||
<td align="left"> | |||
<math>~ | |||
\frac{v_0^2}{2}~ \ln\biggl[x^2 + y^2 + \frac{z^2}{q^2} \biggr] \, . | |||
</math> | |||
</td> | |||
</tr> | |||
</table> | |||
=See Also= | =See Also= |
Revision as of 22:31, 29 March 2021
For Paul Fisher
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Overview of Dissertation
Paul Fisher's (1999) doctoral dissertation (accessible via the LSU Digital Commons) is titled, Nonaxisymmetric Equilibrium Models for Gaseous Galaxy Disks. Its abstract reads, in part:
Three-dimensional hydrodynamic simulations show that, in the absence of self-gravity, an axisymmetric, gaseous galaxy disk whose angular momentum vector is initially tipped at an angle, <math>~i_0</math>, to the symmetry axis of a fixed spheroidal dark matter halo potential does not settle to the equatorial plane of the halo. Instead, the disk settles to a plane that is tipped at an angle, <math>~\alpha = \tan^{-1}[q^2 \tan i_0]</math>, to the equatorial plane of the halo, where <math>~q</math> is the axis ratio of the halo equipotential surfaces. The equilibrium configuration to which the disk settles appears to be flat but it exhibits distinct nonaxisymmetric features. . |
All three-dimensional hydrodynamic simulations employ Richstone's (1980) time-independent "axisymmetric logarithmic potential" that is prescribed by the expression,
<math>~\Phi(x, y, z)</math> |
<math>~=</math> |
<math>~ \frac{v_0^2}{2}~ \ln\biggl[x^2 + y^2 + \frac{z^2}{q^2} \biggr] \, . </math> |
See Also
- Type I Riemann Ellipsoids.
- Dimitris M. Christodoulou's (1989) doctoral dissertation (accessible via the LSU Digital Commons) titled, Using Tilted-Ring Models and Numerical Hydrodynamics to Study the Structure, Kinematics and Dynamics of HI Disks in Galaxies.
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