Characterization of m=−1 helicons

Sheridan, T. E.; Chi, Kyeong-Koo

doi:10.1016/s0375-9601(00)00382-0

Cited by 8 publications

(7 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…E to H and H to W transitions occur vary with the helicon source geometry (the diameter in particular) and is typically 100-500 W and 500-800 W, respectively. More discrete jumps at higher rf powers corresponding to various wave modes and wave trapping mechanisms can be seen (Porteous and Boswell 1987, Perry et al 1991, 2002, Degeling et al 1996, Chi et al 1999, Sheridan and Chi 2000. Although not shown here, high β plasmas and very high densities n e 5 × 10 12 cm −3 can be achieved Boswell 2007, Denning et al 2008).…”

Section: Plasma Density and Ionizationmentioning

confidence: 66%

“…Here, for simplicity of comparison, a bulk to sheath density ratio of about (1/0.3) ∼ 3.3 similar to that obtained in a free fall model in a cylinder of length a few tens of centimetres is assumed (Lieberman and Lichtenberg 1994) as shown in figure 16. This ratio varies greatly (from 1 to 10) with operating conditions and with position along the axis especially in the wave mode (Boswell 1974, 1984b, Degeling et al 1996, Degeling 1999, Sheridan and Chi 2000. For the bi-modal inductive mode, the depth of the central dip has also been arbitrarily chosen to be close to 20%.…”

Section: Radial Density Profile and Thrust Reductionmentioning

confidence: 99%

See 1 more Smart Citation

Plasmas for spacecraft propulsion

Charles

2009

J. Phys. D: Appl. Phys.

330

263

View full text Add to dashboard Cite

This review presents the basics of plasma discharges applied to electric spacecraft propulsion. It briefly reports on the mature and flown technologies of gridded ion thrusters and Hall thrusters before exploring the recent yet immature technology of plasma thrusters based on expansion from low pressure high density inductively coupled and wave-excited plasma sources, e.g. the radiofrequency helicon source. Prototype development of plasma engines for future space travel is discussed using the example of the helicon double layer thruster. A summary of highlights in electric propulsion based space missions gives some insight into the challenges of future high power missions in more remote regions of space.

show abstract

Section: Plasma Density and Ionizationmentioning

confidence: 66%

Section: Radial Density Profile and Thrust Reductionmentioning

confidence: 99%

Plasmas for spacecraft propulsion

Charles

2009

J. Phys. D: Appl. Phys.

330

263

View full text Add to dashboard Cite

show abstract

“…The m = −1 mode is heavily damped and has only been observed as part of a superposition with other modes. 9 The axial propagation of helicon waves has also been studied with results that agree well with the theory. 10 Helicon plasmas have been investigated in nonuniform magnetic field configurations.…”

Section: Wave Propagation Downstream Of a High Power Helicon In A Dipmentioning

confidence: 52%

Wave propagation downstream of a high power helicon in a dipolelike magnetic field

et al. 2010

View full text Add to dashboard Cite

The wave propagating downstream of a high power helicon source in a diverging magnetic field was investigated experimentally. The magnetic field of the wave has been measured both axially and radially. The three-dimensional structure of the propagating wave is observed and its wavelength and phase velocity are determined. The measurements are compared to predictions from helicon theory and that of a freely propagating whistler wave. The implications of this work on the helicon as a thruster are also discussed.

show abstract

“…It seems that the ratio is more than a specific value. This ratio is equal to 2 10 9 and 4 10 cm G , 9 3 1…”

Section: Volume Gradientmentioning

confidence: 94%

“…As a result, they used a helical antenna in their subsequent work [6]. The propagation and damping properties of the m 1 =  modes have been studied in many theoretical and experimental works [7][8][9][10][11][12][13][14]. The value of the density gradient is an important parameter in the propagation of the m 1 =mode [2,4,7,13].…”

Section: Introductionmentioning

confidence: 99%

Directional power absorption in helicon plasma sources excited by a half-helix antenna

Afsharmanesh

Habibi

2017

Plasma Sci. Technol.

View full text Add to dashboard Cite

This paper deals with the investigation of the power absorption in helicon plasma excited through a half-helix antenna driven at 13.56 MHz. The simulations were carried out by means of a code, HELIC. They were carried out by taking into account different inhomogeneous radial density profiles and for a wide range of plasma densities, from 10 cm 11 3 to 10 cm. 13 3-The magnetic field was 200, 400, 600 and 1000 G. A three-parameter function was used for generating various density profiles with different volume gradients, edge gradients and density widths. The density profile had a large effect on the efficient Trivelpiece-Gould (TG) and helicon mode excitation and antenna coupling to the plasma. The fraction of power deposition via the TG mode was extremely dependent on the plasma density near the plasma boundary. Interestingly, the obtained efficient parallel helicon wavelength was close to the anticipated value for Gaussian radial density profile. Power deposition was considerably asymmetric when the n B 0 ratio was more than a specific value for a determined density width. The longitudinal power absorption was symmetric at approximately n 10 cm , 0 11 3 = irrespective of the magnetic field supposed. The asymmetry became more pronounced when the plasma density was 10 cm. 12 3-The ratio of density width to the magnetic field was an important parameter in the power coupling. At high magnetic fields, the maximum of the power absorption was reached at higher plasma density widths. There was at least one combination of the plasma density, magnetic field and density width for which the RF power deposition at both side of the tube reached its maximum value.

show abstract

Characterization of m=−1 helicons

Cited by 8 publications

References 11 publications

Plasmas for spacecraft propulsion

Plasmas for spacecraft propulsion

Wave propagation downstream of a high power helicon in a dipolelike magnetic field

Directional power absorption in helicon plasma sources excited by a half-helix antenna

Contact Info

Product

Resources

About