Magnetic reconnection exhausts at the boundaries of small interplanetary magnetic flux ropes

摘要

Context. Small interplanetary magnetic flux ropes (SIMFRs) are commonly observed by spacecraft at 1 AU. Aims. We provide a mechanism to decrease the dimensions of some SIMFRs as they propagate away from the Sun. Methods. We carefully examined the high-resolution magnetic field and plasma data from the Wind spacecraft during the period 1995-2005 to identify X-line magnetic reconnection exhausts at the boundaries of SIMFRs. Results. We identified nine X-line magnetic reconnection exhausts at the boundaries of SIMFRs, which were destroying the flux within the related SIMFRs. Conclusions. These observational facts indicate that the boundaries of some SIMFRs were still evolving through interaction with the background solar wind, and their spatial scales would diminish gradually.