The light curves and duration of MXB 221120. Panel a: Light curve in 10 ms resolution and duration (T₉₀). The dashed red line in the top panel represents the background level. The blue shadow region in lower panel represents the background range. Panel b: Light curves in different energy bands observed by GECAM-B. Panel c: Light curve fitting with the FRED function. The light curve and FRED profile is plotted in the top panel, and the residuals are plotted in the lower panel.