Physics Letters A 329 (2004) 162–164 www.elsevier.com/locate/pla Comment Comment on: “Theory of vortex flows in partially ionized magnetoplasmas” [Phys. Lett. A 326 (2004) 267] J. Vranješ a,b,∗ , M.Y. Tanaka b , M. Kono c , S. Poedts a a Center for Plasma Astrophysics, Celestijnenlaan 200B, 3001 Leuven, Belgium b National Institute for Fusion Science, 322-6 Oroshi-cho, Toki City 509-5292, Japan c Faculty ofPolicy Studies, Chuo University, Hachioji, Tokyo 192-0393, Japan Received 24 May 2004; accepted 24 June 2004 Available online 6 July 2004 Communicated by F. Porcelli In a recent publication, viz. [Phys. Lett. A 326 (2004) 267], Jovanovi´ c and Shukla (J. and S. in the rest of the text) have criticized some of our work [1,2] in which we have described our experiment and presented a corresponding theoretical model of an observed static tripolar structure. J. and S. have tried to give a common theory for the tripolar vortex [1,2] and the Burgers vortex [3,4], which we have observed in an another experiment. We shall comment on this criticism of our work and we will show that this criticism is either wrong or not related to our experiment and theoretical model. 1. We remark that J. and S. mix the physics of the two independent experiments we carried out. In the first page of their criticism they speak about “plasma typhoones” (Burgers vortex) with the statement of an “anti-  E ×  B rotation” caused by the neutral drag. In fact, the Burgers vortex we observed in our experiment rotated in the  E ×  B direction (helium plasma), as is clearly described in Ref. [4]. The mentioned anti-  E ×  B rotation was observed only in the other experiment (argon plasma) with a tripolar vortex. We stress that in no case the Burgers vortex and the tripole were observed in the same plasma. This is simply because the physical background of both experiments was drastically different. For example, we used an helium plasma in the case of the Burgers vortex, and an argon plasma in the case of the tripole vortex. Moreover, the electron temperature and pressure in the experiment with the helium plasma (Burgers vortex) were 20–25 eV and ≈ 8 × 10 −4 Torr, while in the other experiment (argon plasma) they were 3 eV and 10 −2 Torr. Also, the corresponding temperature ratios were T i /T e = 1/20 and T i /T e = 1/3, respectively, etc. DOI of original article: 10.1016/j.physleta.2004.04.040. * Corresponding author. E-mail address: jvranjes@yahoo.com (J. Vranješ). 0375-9601/$ – see front matter  2004 Elsevier B.V. All rights reserved. doi:10.1016/j.physleta.2004.06.075