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Colliding Galaxies Documents

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Main Document

Colliding Galaxies 

written by Wolfgang Christian and Kyung Taek Lim

The Colliding Galaxies Model is an implementation of Alar and Juri Toomres' 1972 super computer model showing the formation of galactic bridges and tails under the assumption that galactic cores are point masses and that one galactic core is surrounded by 2D concentric rings of orbiting stars.  The model assumes is that the stars (test particles) orbiting the galactic cores are non-interacting.  When the two galaxies pass one another, tidal forces deform the star distribution into classic tidal features.  Our EJS model reproduces this result showing that there is a long curving tail and that only the outermost ring of stars is affected by its companion galaxy. A thin bridge is also formed and some of the stars are captured by the companion galactic core.

The Colliding Galaxies Model Model was developed as a final project in a sophomore-level Computational Physics course (Phy 200) using the Easy Java Simulations (EJS) modeling tool.  It is distributed as a ready-to-run (compiled) Java archive.  Double clicking the ejs_mech_orbits_CollidingGalaxies.jar file will run the program if Java is installed.

Published May 16, 2009
Last Modified June 3, 2014

This file has previous versions.

Supplemental Documents

Poster Presentation 

Physics 200 poster presented during the 2009 Davidson College student research symposium.

Last Modified January 11, 2010

Source Code Documents

Colliding Galaxies source code 

The source code zip archive contains an XML representation of the Colliding Galaxies Model.  Unzip this archive in your EJS workspace to compile and run this model using EJS.

Published May 16, 2009
Last Modified June 3, 2014

This file has previous versions.

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