Geomagnetic conditions (Kp, Dst, and the AU and AL indices) and IMF z-component (in GSM coordinates) on 1–2 June 2008. In this period, the geomagnetic activity was quite low. Vertical dashed lines indicate our observation periods corresponding to each panel of Fig. 4. We used the IMF data measured by the MAG instrument onboard the ACE spacecraft. The IMF data are presented with a 44-min time delay.