A non-force-free approach to the topology of magnetic clouds in the solar wind

Details A non-force-free approach to the topology of magnetic clouds in the solar wind A non-force-free approach to the topology of magnetic clouds in the solar wind

Jan 2002

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2002jgra..107.1002h&link_type=abstract

Journal of Geophysical Research (Space Physics), Volume 107, Issue A1, pp. SSH 1-1, CiteID 1002, DOI 10.1029/2001JA900100

Astronomy and Astrophysics

Astrophysics

29

Solar Physics, Astrophysics, And Astronomy: Magnetic Fields

Scientific paper

We present a new model for the topology of magnetic clouds at 1 AU that relates the magnetic field vector with the current density of the cloud without assuming the force-free condition. In addition, the model is formulated in such a way that it can be fitted directly to the data without the need of initially determining the flux rope axis by minimum variance. The model provides both the magnetic field strength and the direction in just one fitting procedure. In addition to the orientation of its axis and the relative closest-approach distance between the spacecraft and the cloud axis, the fit of the model to the experimental data allows an estimation of the current density of plasma inside the magnetic cloud. From our study on several clouds we conclude that this has values of the order of 10-12 C m-2 s-1. Compared with the force-free model, although the improvement gained in the χ2 values is not very great, the fitting procedure is shorter and easier, and the number of parameters involved has been reduced from seven to five. Our model also lets us check the validity of force-free approximation by the calculation of the value of the current density perpendicular to the flux rope, j⊥ = j × B/|B|. This component is assumed to be zero in the force-free model, but for all analyzed cases we obtain a nonzero value. This finite value implies the existence of pressure gradients inside the cloud that cannot be explained with a force-free approximation. In this paper, four cases are presented that have already been analyzed in the literature. We show that our model can explain the profiles of the magnetic field as a magnetic cloud passes a spacecraft.

Affiliated with

Also associated with

No associations

Rating

A non-force-free approach to the topology of magnetic clouds in the solar wind does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with A non-force-free approach to the topology of magnetic clouds in the solar wind, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A non-force-free approach to the topology of magnetic clouds in the solar wind will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1335729