PPPL-4145 is available in <a href="PPPL-4145.pdf">pdf</a> format (462 KB).

<p>
<b>Physical Origin of the Quadrupole Out-of-plane Magnetic Field in Hall-MHD Reconnection</b>
</p>

<p>
<b>Authors:</b> Dmitri A. Uzdensky and Russell M. Kulsrud
</p>

<p>
<b>Date of PPPL Report:</b> January 2006
</p>

<p>
<b>Submitted to:</b> Physics of Plasmas</p>


<p>

A quadrupole pattern of the out-of-plane component of the magnetic field inside a reconnection region is seen as an important signature of the Hall-magnetohydrodynamic (Hall-MHD) regime of reconnection. It has been first observed in numerical simulations and just recently confirmed in the MRX experiment. In this study, we analyze the physical origin of the quadrupole field and trace it to a current of electrons that flows along the lines in and out of the inner reconnection region to maintain charge neutrality. We further discuss the role the quadrupole field plays in the overall dynamics of the reconnection process.







</p>