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Publications

Refereed Publications

G.J.J. Botha, A.M. Rucklidge, N.E. Hurlburt, Formation of magnetic flux tubes in wedge geometry, Geophysical and Astrophysical Fluid Dynamics, 106, 701, (2012)

G.J.J. Botha, T.D. Arber, A.K. Srivastava, Observational signatures of the coronal kink instability with thermal conduction, ApJ, 745, 53, (2012)

G.J.J. Botha, A.M. Rucklidge, N.E. Hurlburt, Nonlinear nonaxisymmetric convection around magnetic flux tubes, ApJ, 731, 108, (2011)

G.J.J. Botha, T.D. Arber, V.M. Nakariakov, Y.D. Zhugzhda, Chromospheric resonances above sunspot umbrae, ApJ, 728, 84, (2011)

G.J.J. Botha, T.D. Arber, A.W. Hood, Thermal conduction effects on the kink instability in coronal loops, AA, 525, A26, (2011)

T.D. Arber, G.J.J. Botha, C.S. Brady, Effect of solar chromospheric neutrals on equilibrium field structures, ApJ, 705, 1183, (2009)

G.J.J. Botha, F.H. Busse, N.E. Hurlburt, A.M. Rucklidge, Numerical simulations of rotating axisymmetric sunspots, MNRAS, 387, 1445, (2008)

G.J.J. Botha, A.M. Rucklidge, N.E. Hurlburt, Nonaxisymmetric instabilities of convection around magnetic flux tubes, ApJ Letters, 662, L27, (2007)

G.J.J. Botha, E.A. Evangelidis, Reply to comment on "Relativistic Landau resonances", JGR, 112, A05206, (2007)

G.J.J. Botha, A.M. Rucklidge, N.E. Hurlburt, Converging and diverging convection around axisymmetric magnetic flux tubes, MNRAS, 369, 1611, (2006)

E.A. Evangelidis, G.J.J. Botha, Relativistic Landau resonances, JGR, 110(A2), A02216, (2005)

G.J.J. Botha, E.A. Evangelidis, Cylindrical linear force free fields with toroidal flux surfaces, MNRAS, 350, 375, (2004)

E.A. Evangelidis, G.J.J. Botha, A new family of solutions of the force free field equation, Solar Physics, 213(1), 69, (2003)

F.P. Keenan, G.J.J. Botha, A. Matthews, K.D. Lawson, K.L. Bell, C.A. Ramsbottom, I.H. Coffey, M. O'Mullane, A comparison of theoretical line intensity ratios for Ni XII with extreme ultraviolet observations from the JET tokamak, Journal of Physics B, 34(4), 639, (2001)

G.J.J. Botha, T.D. Arber, V.M. Nakariakov, F.P. Keenan, A developed stage of Alfvén wave phase mixing, AA, 363, 1186, (2000)

F.P. Keenan, G.J.J. Botha, A. Matthews, K.D. Lawson, I.H. Coffey, Extreme ultraviolet emission lines of Ni XII in laboratory and solar spectra, MNRAS, 318, 37, (2000)

E.A. Evangelidis, L.L. Vaughan, G.J.J. Botha, The structure of force free fields, Solar Physics, 193(1/2), 17, (2000)

G.J.J. Botha, M.G. Haines, R.J. Hastie, The effect of sheared diamagnetic flow on turbulent structures generated by the Charney-Hasegawa-Mima equation, Phys Plasmas, 6(10), 3838, (1999)

 

Examined Theses

G.J.J. Botha, A two dimensional simulations of electrostatic drift wave turbulence in plasmas, PhD Thesis, Imperial College, London, UK, (1997)

G.J.J. Botha, Magnetic helical fields in a tokamak, MSc Research Report, University of the Witwatersrand, Johannesburg, South Africa (1990)

 

Published Reports

G.J.J. Botha, The plasma focus: a literature survey, AEC of SA Ltd, PIN-1265(B/R), August 1991

G.J.J. Botha, Magnetic helical fields in a tokamak, AEC of SA Ltd, PIN-1206(B/R), September 1990

G.J.J. Botha, Plasma centrefuge: a literature survey, AEC of SA Ltd, PEL-90/03(B/R), April 1990

 

Conference Proceedings

E.A. Evangelidis, G.J.J. Botha, The equilibrium equation in skew configurations, 34th EPS Conference on Plasma Physics, Warwaw, Poland, 2-6 July 2007, P4.070

G.J.J. Botha, A.M. Rucklidge, N.E. Hurburt, Numerical simulations of sunspots, IAU Symposium 239: Convection in Astrophysics, Prague, Czech Republic, 21-25 August 2006, Proc. IAU, Vol. 2, p. 507, (CUP, Cambridge), F. Kupka, I.W. Roxbridge, K.L. Chan (eds.)

G.J.J. Botha, E.A. Evangelidis, Differential rotation and angular momentum, IAU Symposium 239: Convection in Astrophysics, Prague, Czech Republic, 21-25 August 2006, Proc. IAU, Vol. 2, p. 451, (CUP, Cambridge), F. Kupka, I.W. Roxbridge, K.L. Chan (eds.)

G.J.J. Botha, E.A. Evangelidis, Particle orbits in an axisymmetric equilibrium plasma, 33rd EPS Conference on Plasma Physics, Rome, Italy, 19-23 June 2006, P5.065

E.A. Evangelidis, G.J.J. Botha, Dynamics on a surface of equilibrium, 33rd EPS Conference on Plasma Physics, Rome, Italy, 19-23 June 2006, P2.048

G.J.J. Botha, A.M. Rucklidge, F.H. Busse, N.E. Hurlburt, Numerical simulations of rotating sunspots, SOHO-17: 10 Years of SOHO and Beyond, Giardini Naxos, Sicily, Italy, 7-12 May 2006, ESA SP-617, July 2006, P29

E.A. Evangelidis, G.J.J. Botha, Angular momentum coupling in tokamaks,32nd EPS Conference on Plasma Physics, Tarragona, Spain, 27 June - 1 July 2005, P1.130

G.J.J. Botha, A.M. Rucklidge, N.E. Hurlburt, Dynamics of convection around axisymmetric magnetic flux tubes, 31st EPS Conference on Plasma Physics, London, UK, 28 June 2 July 2004, ECA 28G, P-2.062

G.J.J. Botha, R.J. Hastie, M.G. Haines, Alpha particles in inhomogeneous electrostatic fluctuations, 31st EPS Conference on Plasma Physics, London, UK, 28 June 2 July 2004, ECA 28G, P-4.199

E.A. Evangelidis, G.J.J. Botha, Landau resonances between charged particles and plasma waves, 31st EPS Conference on Plasma Physics, London, UK, 28 June 2 July 2004, ECA 28G, P-5.148

G.J.J. Botha, E.A. Evangelidis, Cylindrical solutions of force free magnetic fields, IAU Symposium 219: Starts as Suns: Activity, Evolution and Planets, Sydney, Astralia, 21-25 July 2003, ISBN: 1-58381-163-X

E.A. Evangelidis, G.J.J. Botha, Alfvén wave - particle interactions, IAU Symposium 219: Starts as Suns: Activity, Evolution and Planets, Sydney, Astralia, 21-25 July 2003, ISBN: 1-58381-163-X

E.A. Evangelidis, G.J.J. Botha, Alfvén wave - particle interactions,30th EPS Conference on Controlled Fusion and Plasma Physics, St. Petersburg, Russia, 7-11 July 2003, ECA 27A, P-3.214

E.A. Evangelidis, G.J.J. Botha, A new family of solutions of the force free field equation, SOLMAG: Magnetic Coupling of the Solar Atmosphere Euroconference and IAU Colloquium 188, Santorini, Greece, October 2002, ESA SP-505, p. 401, H. Sawaya-Lacoste (ed.)

M.E. Phillips, F.P Keenan, S.J. Rose, G.J.J. Botha, M.E. Foord, R.F. Heeter, G.J. Ferland, Photoionized Plasma Calculations using Laboratory and Astrophysical Models, Spectroscopic Challenges of Photoionized Plasmas, ASP Conference Series, Vol. 247, p. 123, (2001), G.J. Ferland, D.W. Savin (eds.)

E.A. Evangelidis, G.J.J. Botha, A cylindrical formulation of force free magnetic fields, IAU Symposium 203: Recent Insights into the Physics of the Sun and Heliosphere: Highlights from SOHO and Other Space Missions, p. 270, (2001), P. Brekke, B. Fleck, J.B. Gurman (eds.)

G.J.J. Botha, M.G. Haines, R.J. Hastie, A 2D simulation of electrostatic drift wave turbulence in plasmas, 24th EPS Conference on Controlled Fusion and Plasma Physics, Berchtesgaden, Germany, 9-13 June 1997

G.J.J. Botha, M.G. Haines, R.J. Hastie, Electrostatic drift wave turbulence simulation, International Workshop on Transport in Fusion Plasmas, Göteborg, Sweden, 13-16 June 1994