Department - Author 1
Physics Department
Degree Name - Author 1
BS in Physics
Date
2015
Primary Advisor
Jodi Christiansen
Abstract/Summary
The spectrum of two blazar objects, 1ES 1959+650 and 1ES 2344+514, are analyzed for evidence of interactions with the Extragalactic Background Light (EBL), using combined data from the Very Energetic Radiation Imaging Telescope Array System and the Fermi Gamma-ray Space Telescope, By analyzing the distinct curvature across the combined spectrum, we infer that the very-high energy (VHE) gamma-rays must be attenuated by interactions with the EBL. We also find that the measured 1ES 1959+650 spectrum is sensitive to the intrinsic blazar model, with a preference for a power-law with an exponential cutoff (EPWL). The measured curvature is a combination of the EBL attenuation and the exponential cut-off, as determined by statistical tests assuming that there is no EBL. Finally, a test of the optical depth due to the EBL indicates that the two blazars are consistent with the amount of EBL given by the Franceschini model of intergalactic optical depth.
URL: https://digitalcommons.calpoly.edu/physsp/132
Included in
Cosmology, Relativity, and Gravity Commons, External Galaxies Commons, Other Astrophysics and Astronomy Commons