Left: samples of magnetic field lines from the optimized PFSS magnetic field model with the source surface at 2.1 R⊙, in the plane cut through 18° longitude. PSP certainly crossed magnetic field lines connected to field lines A (state 1) and B (state 2). Middle: plasma density (top), speed (middle), and temperature profiles computed by an MHD code along five flux tubes around field-line A (in red) and around field-line B (in blue). Right: expansion factor (top), heating profile (middle), and magnetic field intensity profiles computed by the MHD code along five flux tubes around field-line A (in red) and around field-line B (in blue).