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To understand basic principles of dusty plasmas, we define some of basic

features:

1.7.1 Debye Length

The Debye length provides the distance for which the influence of

electric field of individual charged particle is felt by the other charged
particles inside the plasma. These particles rearrange themselves to shield

all electrostatic fields within the Debye distance., Debye length in dusty

plasmas is given by [ 59]:

   
  =p 2 2  (1.12)
  +  

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where   =(    4   ) 12 is the Debye length of ions, and   and  

are the ion temperature and density, respectively.

1.7.2 Neutrality Condition

At equilibrium state, neutrality condition is

  +   +     =0 (1.13)

where   =   (−  ) is the charge on grain surface for positive (negative)

charged grains and   is the number of charge residing on grain surface.

1.7.3 Coupling Parameter (CP)

The strongly or weakly correlation depends on the Coulomb coupling
parameter
 2  )
Γ  =[  ] (−    (1.14)
 (    )

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