Processes, Tasks, and Procedures (Tatiana Criucova)

     My overall task for this internship is to create a catalog of the outflows of various young stars. This catalog consists of four different types of images: one that shows the outflow at blue (or low) velocities and red (or high) velocities, one that shows it in the near-infrared, one in the optical wavelength (what we would see if we looked at it with our eyes), and finally one from the Spitzer Space Telescope which takes images in the infrared. In order to begin this catalog, I need to first identify the outflows. To do this, I open a program called DS9 where I am able to open this file that resembles a video. It contains many images (going from low velocity to high velocity) that I can play through in order to find outflows. In order to make this easier, I can load a region file right onto the images which shows me where different stars are. These names are color coded according to where the star is in its process of formation, with red meaning that it is in its early stages and green meaning that the star is almost fully formed. The green stars are the least likely to have outflows. I zoom in on a star of my choice and I play through the images to see if I can see any sort of outflow coming from the star. If I am not sure that it is an outflow, I can open an image of that part of the sky and compare it side by side with what I think the shape of the outflow is. If that is still not enough to understand if it is outflow, noise, or part of the incoming cloud in the images, I can open a program called Glue which allows me to glue the images together on top of each other and zoom into the point of interest. This lets me truly see if the movement is that of an outflow. 

      Once I have identified what I think is a potential outflow, I open a program called CASA. Using this, I can create something called a moments map which is basically an intensity map of the outflows. In order to do this, I first need to define in code what file I would like to make this image for. Once I do this, I tell the computer that I want to integrate across only certain channels (usually around 5 channels where the outflow seems to be at its peak). The channels are the image at different velocities. After I create a large intensity map of the whole image, I need to create a sub-image of the region of the sky where the outflow is. To do this, I enter in the coordinates of the lower right corner of the region and then the upper left corner. Once this is done, I need to change the intensity map into a format that the program DS9 can read (a 'fits' image format). I create these images for both the low velocity outflow and the high velocity outflows of the stars.

     Once I create these two images, I can create them into a red and blue image in DS9. Again, the blue part of the image will be the outflow at a low velocity while the red image is the outflow at a high velocity. Finally, I open up all of the other image files. I match all of them to the location of the young star so they are all focused on the same object. Once I do this, I can crop the images to the same size and then create a graph out of them with the information of their location in the sky. Then, I screenshot all of these images and place them into the document that serves to catalog them.