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essential aim for new dusty plasmas studies is the control of contamination

in plasmas-processing reactors and preventing dusty particles to contact

with surfaces.

Dust Acoustic Waves

Dusty plasmas support new types of waves and instabilities which do

not exist in electron-ion plasma. The first theoretical work was made by
Rao et al. [67] and is called "dust-acoustic waves". It is an electrostatic

acoustic-like mode where electron-ion thermal pressures causing restoring

force while inertia is caused by heavier dusty component, with resulting

phase velocity in the form

s
          
  = = +  (1.15)
     1+( )(1 −   )
 
 

where  =     is density of the dust grains relative to the ions. The
dispersion relation (1.15) was obtained from a fluid analysis by Rao et al.

[67] and D’Angelo [68], and is valid in the limit (  )  1 [69].
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Dust Ion Acoustic Waves

Dusty plasmas without external magnetic field support low fre-

quency electrostatic DAWs [67] and dust-ion acoustic waves (DIAWs) [70].

The DIAWs is a fast wave with phase velocity lying between electron and

ion thermal velocities with frequency much larger than dusty plasma fre-
quency. In DIAWs, restoring force comes from inertialess electrons pres-

sure and ion mass provides the inertia. Due to electrons-ions numbers,

DIAWs phase velocity is larger than the IAWs [70].
Many investigations have been done in DIAW features [70, 73]. Ma-

mun and Shukla [73] examined cylindrical and spherical DIAWs proper-

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