### Abstract

The nonlinear Landau damping and growth of longitudinal waves in a magnetic field is studied experimentally. It is observed that a finite-amplitude cyclotron harmonic wave may decay nonresonantly into a similar, small-amplitude wave. This perturbed wave dan be amplified exponentially by increasing the amplitude of the finite-amplitude wave. Similarly, an externally launched small-amplitude test wave, having the same frequency as the perturbed wave, can be amplified at a comparable rate. The spatial growth of the test wave is in agreement with the predictions of a third-order mode-coupling equation. Using a calibrated interferometer system, the nonlinear Landau damping coupling coefficients (matrix elements) are measured quantitatively, and are found to be in good agreement with theory.

Original language | English |
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Pages (from-to) | 297-303 |

Number of pages | 7 |

Journal | Physics of Fluids |

Volume | 15 |

Issue number | 2 |

Publication status | Published - 1972 |

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### ASJC Scopus subject areas

- Condensed Matter Physics
- Physics and Astronomy(all)
- Mechanics of Materials
- Computational Mechanics
- Fluid Flow and Transfer Processes

### Cite this

*Physics of Fluids*,

*15*(2), 297-303.

**Experimental studies of nonlinear Landau damping and growth of plasma waves in a magnetic field.** / Chang, Robert P. H.; Porkolab, M.

Research output: Contribution to journal › Article

*Physics of Fluids*, vol. 15, no. 2, pp. 297-303.

}

TY - JOUR

T1 - Experimental studies of nonlinear Landau damping and growth of plasma waves in a magnetic field

AU - Chang, Robert P. H.

AU - Porkolab, M.

PY - 1972

Y1 - 1972

N2 - The nonlinear Landau damping and growth of longitudinal waves in a magnetic field is studied experimentally. It is observed that a finite-amplitude cyclotron harmonic wave may decay nonresonantly into a similar, small-amplitude wave. This perturbed wave dan be amplified exponentially by increasing the amplitude of the finite-amplitude wave. Similarly, an externally launched small-amplitude test wave, having the same frequency as the perturbed wave, can be amplified at a comparable rate. The spatial growth of the test wave is in agreement with the predictions of a third-order mode-coupling equation. Using a calibrated interferometer system, the nonlinear Landau damping coupling coefficients (matrix elements) are measured quantitatively, and are found to be in good agreement with theory.

AB - The nonlinear Landau damping and growth of longitudinal waves in a magnetic field is studied experimentally. It is observed that a finite-amplitude cyclotron harmonic wave may decay nonresonantly into a similar, small-amplitude wave. This perturbed wave dan be amplified exponentially by increasing the amplitude of the finite-amplitude wave. Similarly, an externally launched small-amplitude test wave, having the same frequency as the perturbed wave, can be amplified at a comparable rate. The spatial growth of the test wave is in agreement with the predictions of a third-order mode-coupling equation. Using a calibrated interferometer system, the nonlinear Landau damping coupling coefficients (matrix elements) are measured quantitatively, and are found to be in good agreement with theory.

UR - http://www.scopus.com/inward/record.url?scp=0347810581&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0347810581&partnerID=8YFLogxK

M3 - Article

VL - 15

SP - 297

EP - 303

JO - Physics of Fluids

JF - Physics of Fluids

SN - 0031-9171

IS - 2

ER -