  The primary goal of this project was to use the given data of four emission
lines from two ultra-luminous infrared galaxies to calculate the molecular gas
mass and dynamical mass of each galaxy. These quantities can provide valuable
information about a galaxy's age, star formation properties, and molecular
make-up. Ultra-luminous infrared galaxies are formed from the merger or
interaction of gas-rich galaxies, and are classified by having a luminosity of
greater than 1012 L?. The presence of molecular gas clouds and dust encourages
formation of young, bright stars in these galaxies, but also makes it difficult
to measure the total gravitational and molecular masses, since molecular
hydrogen is virtually undetectable within gas clouds. Our data instead observed
emissions of carbon monoxide (CO) from the two ULIRGs at transitions of J= 1 ->
0 orJ= 2 -> 1. The software Difmap was used to map the interferometer data
obtained from the Plateau de Bure Interferometer (PdBI). Our data was cleaned,
filtered, and subsequently used to generate UV-plots of the emissions, along
with other values needed for calculations. Some of the key results include that
iras 15250 is much younger as it has not used up a majority of its molecular
gas while iras 17208 is older because it has used it up, the gas mass fraction
can be used to estimate the amount of dark matter present in the galaxy, and
that the gas content and the central surface brightness of the disk are
directly correlated.
