Fig. 39.

Upper panels ACE measurements of the magnetic power versus time in three different frequency ranges. Lower panels PSDs at four time intervals identified by the vertical bars in the upper panels. The local proton cyclotron frequency ${\mathit{\nu }}_{pc}$ is shown in each of the four lower panels. The two shocks arrived at ACE at $\sim$0644 UT on August 6, 1998, and $\sim$0211 UT on February 18, 1999, i.e., $<40$ min earlier than at Wind. ACE was located at the L1 point and separated from Wind by $\sim 135R_E$ and $\sim 164R_E$, respectively. Image reproduced with permission from Desai et al. (2012), copyright by AIP