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

H. Q. Feng^1,2, D. J. Wu³, J. M. Wang¹ and J. W. Chao⁴

¹ College of Physics and Electronic Information, Luoyang Normal University, Luoyang 471022, PR China
e-mail: fenghq9921@163.com
² State Key Laboratory of Space Weather, Center for Space Science and Applied Research, Chinese Academy of Sciences, Beijing 100190, PR China
³ Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008, PR China
⁴ Institute of Space Science, National Central University, Chungli 32001, Taiwan

Received: 21 March 2010
Accepted: 15 December 2010

Abstract

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.