Selection of dust particles in the self-organized dust structures V.Yu. Karasev St. Petersburg State University

The task Parameters of initial particles: Parameters of levitated particles?

Reasonable parameters Average size - d And form-factor - f d = (x + y)/2, f = x/y Scale 2.8 мкм

Discharge chamber: 1 – moveable diaphragm; 2 – structure in the trap above the tube wall; 3 - structures in the trap in striations; 4 container with powder; 5 device for collection of particle; 6 cathode; 7 anode; 8 tap; 9 magnet.

experiment

complex shape structures in strata vertical section of double structure

Head Te1 and body Te2 of strata

Sizes and form-factor distributions of particles ex- tracted from dust trap in striation in kripton ,

Sizes and form-factor distributions in neon

Interpretation of selection in strata in Ne d=6,5 mkm d=3 mkm f=2 f=1 q= 2 104 e q= 7 103 e E=10 V/сm E=3 V/сm m1g = E1q1, m2g = E2q2, q/m=const selection by f

New effect – selection by form-factor discharge plasma intense charging processes in head of strata Te1 (2-4 eV) plasma selected particles f=2 moderate charging processes in body of strata Te2 (1-2 eV) plasma selected particles f=1

from Big size to nano particles

Thank you for attention

New dusty trap, dust structure formed over the bottom wall of the discharge chamber near the current turn

30000 particles, Р = 0.3 Тоr, i = 1.6 мА. Ne, Kr

Selection in "dead volume“ of chamber Kr, i = 1.6 мА, Р = 0.3 Тоr. d = 2.17 mkm

dependence of selection parameters on the dimensional factor (volume of dust structure) d = 2.17 мкм. f 1 – 1.25. small dust structure d = 2.35 мкм. f 1.5 – 2. big dust structure