Kumar, Santhosh T. A.Blackwell, Boyd D.Howard, JohnHarris, Jeffrey H.2015-12-082015-12-081070-664Xhttp://hdl.handle.net/1885/38437Plasma confinement in the vicinity of vacuum magnetic islands near the magnetic axis in the H-1NF heliac [S. M. Hamberger et al., Fusion Technol.17, 123 (1990)] has been experimentally studied in a low temperature argon plasma. Experimental results indicate that, under favorable conditions, these low order (m=2)islands near the core of the plasma serve as “pockets” of higher electron density. This results in significant profile modifications including enhancement of the core radial electric field to a large positive value, possibly through an electron-root ambipolar condition. The characteristics of islands are found to be dependent on the plasma collisionality and island width.This research was supported in part by the Australian Research Council Grant No. DP0344361 and the U.S. Department of Energy under Contract No. DE-AC05- 00OR22725 with UT-Battelle, LLC.http://www.sherpa.ac.uk/romeo/issn/1070-664X..."Publishers version/PDF may be used on author's personal website, institutional website or institutional repository" from SHERPA/RoMEO site (as at 9/12/15). Copyright 2010 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Physics of Plasmas and may be found at https://doi.org/10.1063/1.3474946Keywords: Ambipolar; Argon plasmas; Electron densities; Favorable conditions; Low order; Low temperatures; Magnetic axis; Magnetic island; Plasma collisionality; Positive value; Profile modification; Radial electric field; Argon; Electric fields; Plasma confinement201010.1063/1.34749462016-02-24