PCU 2 count rate (2–18 keV), after subtraction of its background, is reported as a function of time in the period from 2 October 2009 and 22 October 2009. During the first few days, the last phase of the IGR J17511-3057 outburst is visible. The flux re-brightening is caused by the onset of the XTE J1751-305 outburst, which lasted less than two days. The remaining days show the constant flux due to the Galactic ridge. The superimposed model is the best-fit using a piecewise linear function. Since we are interested in determine the background due to IGR J17511-3057 and the Galactic ridge, we excluded from the fit the XTE J1751-305 outburst. See the text for more details.