Color-Color Analysis of GLIMPSE Point Sources

Daniel Capellupo, University of Rochester
Adviser: Ed Churchwell, University of Wisconsin - Madison

3. Mystery Objects

Using an IDL program created by Prof Bob Benjamin, I was able to select all the objects within a circle around each of the two peaks. There are 8941 objects within the lower peak circle and 6472 objects within the upper peak circle. The following plot shows the same plot as before, but with the two circles drawn over it:

I used this program to output a list of the coordinates (galactic longitude and latitude) for the objects from the two peaks. I then plotted each on a distribution of the sky. The first plot below is just a plot of all the [K]-[8.0]>3 objects. In the second plot, all the upper peak objects are superimposed on the first plot, and in the third plot, all the lower peak objects are superimposed on the first plot:

As you can see just by looking at the two plots, the lower peak objects tend to cluster in dense, star-forming regions, while the upper peak objects are fairly evenly distributed throughout the survey. In order to quantify this observation, I chose two dense regions in the survey and two sparse regions, and I counted how many objects from each peak were located in these regions. The two dense regions are longitude l=14-15 and l=34-35, and the two sparser regions are l=20-21 and l=40-41. The latitude range is equal to the GLIMPSE survey latitude range. I then created an excel chart to show the results, which can be seen here.