Hydrogen column density obtained by integrating the pseudo-distance distribution at the four main peaks in Fig. 2 (highlighted with blue arrows), centered at 406.3 pc (leftmost panel), 475.2 pc (center-left panel), 553.6 pc (center-right panel), and ∼700 pc (rightmost panel). The inset of the last panel shows the two clouds around 700 pc as separate values: the circles refer to the peak at 695.4 pc (Swift-XRT in blue, XMM-Newton in brown for Obs1, and pink for Obs2), and the squares to the peak centered at 728.6 pc (Swift-XRT in green, XMM-Newton in black for Obs1, and red for Obs2). In all the other panels the values from Swift-XRT observations are shown in green, and from XMM-Newton observations in black (Obs1) and red (Obs2).