Analysis of a Sample of BL Lac Objects with the HAWC Observatory
Open Access
- Author:
- Heller, Erica
- Area of Honors:
- Physics
- Degree:
- Bachelor of Science
- Document Type:
- Thesis
- Thesis Supervisors:
- Miguel Alejandro Mostafa, Thesis Supervisor
Richard Wallace Robinett, Thesis Honors Advisor - Keywords:
- HAWC
Gamma-Ray Astronomy
Extragalactic Gamma-Ray Astronomy
AGNs
Blazars
High-Energy Astrophysics - Abstract:
- Only three sources of extragalactic TeV gamma-ray emission have been observed by the High-Altitude Water Cherenkov (HAWC) Gamma-Ray Observatory. Using a pre-selected candidate list of potential TeV-emitting BL Lac objects, we searched for TeV emission using the 2321-day dataset from the HAWC Observatory. Eleven BL Lac objects were investigated. For four of these BL Lac objects, lower energy gamma-ray data was available from the Fermi Large Area Telescope (Fermi-LAT). Using data from Fermi-LAT, we fit a simple power law model to the energy spectrum of each source and used this simple power law model to investigate the region using HAWC. We found no significant TeV gamma-ray emission from these four sources. We set upper limits on the flux from these sources at 1 TeV. For the remaining seven sources, we used three simple power law models due to the lack of lower-energy gamma-ray data. We found no significant TeV gamma-ray emission from these seven sources using all three simple power law models, and we set upper limits on the flux from these sources at 1 TeV for each model. Despite the lack of gamma-ray detection from these sources, we determine that the upper limits set using HAWC data can constrain the extrapolation of a simple power law model into the TeV energy range for three of the four sources with Fermi-LAT data. Through these investigations of BL Lac objects, we provide valuable information about the acceleration mechanisms occurring at these extreme extragalactic objects.