HR plot derived from a grid of simulated spectra, assuming an absorbed power law model, with the HR of XMMU J053348.2−720233 shown in black. See text for a description of the HR simulation and chosen energy bands. The blue lines indicate models on the grid of equal Γ, whereas the red lines mark the models on the grid of equal equivalent hydrogen column N_H,tot = N_H,Gal + N_H,LMC. The dashed red line gives the total N_H measured value through the Galaxy and the LMC (Kalberla et al. 2005) of 2 × 10²¹ cm^-2. The dotted red line gives the combined N_H measured through the Galaxy and the LMC determined by Dickey & Lockman (1990) and Kim et al. (2003), respectively, of 2.5 × 10²¹ cm^-2.