Axial variation of electron number density in thermal plasma spray jets N. K. Joshi, S. N. Sahasrabudhe, K. P. Sreekumar and N. Venkatramani Eur. Phys. J. D, 26 2 (2003) 215-219 Published online: 22 July 2003 DOI: 10.1140/epjd/e2003-00211-9