Gyrokinetic study of impurity mode in reversed-field pinch S. F. Liu, C. L. Zhang, W. Kong, S. C. Guo, J. Q. Dong, L. M. Liu, Q. Liu and Z. Y. Liu EPL, 97 5 (2012) 55004 Published online: 05 March 2012 DOI: 10.1209/0295-5075/97/55004