Solar activities associated with interplanetary magnetic flux ropes Original Research Article

A smoothly rotating interplanetary magnetic field with duration on the order of a day has been detected in solar wind observations. This structure is called an “interplanetary magnetic flux rope.” Here, we studied the relationship between interplanetary magnetic flux ropes observed by Ulysses when it was near the solar limb and coronal mass ejections (CMEs) observed by the Large Angle and Spectrometric Coronagraph (LASCO) on board the Solar and Heliospheric Observatory (SOHO) spacecraft. We found that interplanetary flux ropes with large inclination to the equatorial plane of the Sun were associated with CMEs with large angular widths. The angular widths were measured using the SOHO/LASCO observations. The flux ropes with small inclination were associated with CMEs with small angular widths. These observations suggest that the projection of the erupted flux ropes are observed as CMEs. Interplanetary flux ropes have the same orientation as their solar sources, CMEs.