PoS(HEASA2018)049 Fits to the spectra of broad-line region of active galactic nuclei and opacities for two-photon pair production M. Ntshatsha * Centre for Astro-Particle Physics (CAPP) and Department of Physics, University of Johannesburg, Auckland Park 2006, South Africa E-mail: mfuphin95@gmail.com S. Razzaque Centre for Astro-Particle Physics (CAPP) and Department of Physics, University of Johannesburg, Auckland Park 2006, South Africa E-mail: srazzque@uj.ac.za R.J. Britto University of the Free State, PO Box 339, Bloemfontein 9300, South Africa E-mail: dr.richard.britto@gmail.com Based on the spectral analysis of a composite Hubble Space Telescope (HST) spectrum made of 184 quasar data, we model the emission lines of the broad-line region (BLR) using analytic functions. For simplicity of this paper we neglect effects of the continuum emission, which may be resulting from emission by the accretion disk, and assume the emission of the BLR to be com- posed of the most prominent emission lines that form as a result of ionization and recombination processes within regions of the BLR. We also calculate opacities for gamma-rays propagating in the BLR and interacting with the modeled emission to produce electron-positron (e ± ) pairs. High Energy Astrophysics in Southern Africa - HEASA2018 1-3 August, 2018 Parys, Free State, South Africa * Speaker. c  Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND 4.0). https://pos.sissa.it/