Drift waves

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In plasma physics, a drift wave is a type of collective excitation that is driven by a pressure gradient within a magnetised plasma, which can be destabilised by differences between ion and electron motion (then known as drift-wave instability or drift instability). The equations which describe these waves possess a number of solutions, including ion-acoustic solitary waves, [1] and are roughly analogous to modons. [2]

The drift wave typically propagates across the pressure gradient and is perpendicular to the magnetic field. It can occur in relatively simple configurations such as in a column of plasma with a non-uniform density but a straight magnetic field. [3] Drift wave turbulence is responsible for the transport of particles, energy and momentum across magnetic field lines. [4]

The characteristic frequency associated with drift waves involving electron flow [5] is given by where is the wavenumber perpendicular to the pressure gradient of the plasma, is the Boltzmann constant, is the electron temperature, is the elementary charge, is the background magnetic field and is the number density gradient of the plasma.

References

  1. Meiss, J. D.; Horton, W. (1983-04-01). "Solitary drift waves in the presence of magnetic shear" . The Physics of Fluids. 26 (4): 990–997. doi:10.1063/1.864251. ISSN   0031-9171.
  2. Swaters, Gordon E. (1986-05-01). "Stability conditions andaprioriestimates for equivalent-barotropic modons" . The Physics of Fluids. 29 (5): 1419–1422. doi:10.1063/1.865658. ISSN   0031-9171.
  3. Goldston, Robert J.; Rutherford, Paul H. (1995). "21. Drift waves and instabilities". Introduction to plasma physics. Bristol, UK: Institute of Physics. ISBN   0-7503-0325-5. OCLC   33079555.
  4. Horton, W. (1999). "Drift waves and transport". Reviews of Modern Physics. 71 (3): 735–778. Bibcode:1999RvMP...71..735H. doi:10.1103/RevModPhys.71.735. hdl: 2152/61083 . ISSN   0034-6861. S2CID   122400874.
  5. Chen, Francis F. (2016). "6.8 Resistive Drift Waves". Introduction to plasma physics and controlled fusion (3rd ed.). Cham. ISBN   978-3-319-22309-4. OCLC   933392530.{{cite book}}: CS1 maint: location missing publisher (link)