Simulations of the broad line region of NGC 5548 with CLOUDY code: Temperature determination

Abstract

In this paper an analysis of the physical properties of the Broad Line Region (BLR) of the active galaxy NGC 5548 is presented. Using the photoionization code CLOUDY and the measurements of Peterson et al. (2002), the physical conditions of the BLR are simulated and the BLR temperature is obtained. This temperature was compared to the temperature estimated with the Boltzmann-Plot (BP) method (Popovic et al. 2007). It was shown that the measured variability in the BLR temperature could be due to the change in the hydrogen density.