Analysis of O1 spectrum of binary AGN 4C+37.11 using model M1. Left: Best-fitted O1 spectrum in the 0.7−7.5 keV energy range. Points and solid line in the top panel denote the data and model while the model fitted residual is shown in the bottom panel. The line width of the Fe Kα line is ∼0.19 ± 0.05 keV. Middle: Confidence contour between the line energy and line width. The red, green, and blue contours correspond 1σ, 2σ, and 3σ levels. Right: Δχ² confidence contour of the Fe Kα line energy. The dashed horizontal lines represent different confidence levels of the detection.