Event Title
Modeling the Effect Black Holes Have on the Morphologies of Their Host Galaxies in the Early Universe
Location
Davis 301
Start Date
30-4-2015 9:00 AM
End Date
30-4-2015 10:55 AM
Project Type
Presentation
Description
The effect that Active Galactic Nuclei (AGN) have on the morphology of galaxies was studied by adding point sources of light to distant galaxies absent of an AGN. An active galactic nuclei is a black hole at the center of a galaxy that is radiating extreme amounts of light due to a high influx of matter into the black hole. The galaxies studied were imaged by the Hubble Space Telescope and selected to have a redshift value between z = 1.5 and z = 2.5. Galaxies with host AGN were ruled out based on X-ray imaging from the Chandra Space Telescope over the same region of space. Within these parameters, 13 galaxies were selected representing both elliptical and spiral galaxies. These galaxies were classified and modeled using the program GALFIT to gain measurements of both the sersic index of the light profile of the galaxy, n, and the effective radius of the galaxy, Re. A point source of light was added to the image of each galaxy at 10%, 20%, 30%, 40%, and 50% of the total light of the galaxy, in turn modeling the appearance of an AGN at different intensities. The images with added AGN were modeled again with the program GALFIT to gain measurements of the sersic index and effective radius. The presence of the modeled AGN were found to increase the sersic index while generally causing a decrease in the effective radius.
Faculty Sponsor
Duncan Tate
Sponsoring Department
Colby College. Physics and Astronomy Dept.
CLAS Field of Study
Natural Sciences
Event Website
http://www.colby.edu/clas
ID
1579
Modeling the Effect Black Holes Have on the Morphologies of Their Host Galaxies in the Early Universe
Davis 301
The effect that Active Galactic Nuclei (AGN) have on the morphology of galaxies was studied by adding point sources of light to distant galaxies absent of an AGN. An active galactic nuclei is a black hole at the center of a galaxy that is radiating extreme amounts of light due to a high influx of matter into the black hole. The galaxies studied were imaged by the Hubble Space Telescope and selected to have a redshift value between z = 1.5 and z = 2.5. Galaxies with host AGN were ruled out based on X-ray imaging from the Chandra Space Telescope over the same region of space. Within these parameters, 13 galaxies were selected representing both elliptical and spiral galaxies. These galaxies were classified and modeled using the program GALFIT to gain measurements of both the sersic index of the light profile of the galaxy, n, and the effective radius of the galaxy, Re. A point source of light was added to the image of each galaxy at 10%, 20%, 30%, 40%, and 50% of the total light of the galaxy, in turn modeling the appearance of an AGN at different intensities. The images with added AGN were modeled again with the program GALFIT to gain measurements of the sersic index and effective radius. The presence of the modeled AGN were found to increase the sersic index while generally causing a decrease in the effective radius.
https://digitalcommons.colby.edu/clas/2015/program/351