Variation in the line energies of different cyclotron lines with 3–50 keV luminosity of the source. Circles correspond to the 2011 outburst (Iyer et al. 2015), triangles correspond to the 2015 outburst, and square points represent the results from the current work. The evolution of the 12, 16, 24, 34, and 48 keV are shown in different panels from top to bottom. The dotted lines in the top two panels show the predicted variation in the cyclotron line (E_cyc) and X-ray luminosity (L_X) according to a collisionless shock model.