Undergraduate Honors Theses

Thesis Defended

Fall 2015

Document Type


Type of Thesis

Departmental Honors



First Advisor

Jeremy Darling

Second Advisor

Ryan O'Leary

Third Advisor

Erica Ellingson

Fourth Advisor

Jason Glenn

Fifth Advisor

Adam Norris


Since black holes inhabit galactic centers, when galaxies merge, so must their central black holes. If the two coalescing black holes emit anisotropic gravitational waves, one of the black holes can be ejected from the galactic center, bringing a core of stars with it. Based on the merger history of the Milky Way, it is estimated there are ~300 recoiled black holes in the halo. We present a preliminary spectroscopic search, using the search criteria and list of candidates in O'Leary & Loeb (2012). Although we did not find candidate recoiled black holes, we further optimized the search criteria, using Sloan Digital Sky Survey (SDSS) and Wide-field Infrared Survey Explorer (WISE) magnitudes and colors. More specifically, the SDSS colors (g - r), and (r - i) allow us to constrain the search criteria. Our results contribute to making the search for recoiled black holes more efficient, reducing the amount of false positives that are observed. In the event that a recoiled black hole is found, it would be the first discovery of an elusive intermediate-mass black hole and, as a result, would contribute to our understanding of black hole evolution.