AT Cnc contour plots for the spectral model parameters at 68%, 90%, and 99% confidence levels. From top left to bottom right: Absorbing hydrogen column (in units of 10²²cm⁻²) vs blackbody (kT); blackbody normalization ( L₃₉/D₁₀², where L₃₉ is luminosity in units of 10³⁹erg/s and D₁₀ is the distance in units of 10 kpc) vs blackbody (kT); and cooling flow normalization (mass accretion rate in units of M_⊙yr⁻¹) vs the lowest and highest plasma temperature of the cooling flow.