11

Shape of Atomic Lines Emitted by positive corona discharge

N. Bonifaci, F. Aitken, H. Gharbi Tarchouna, G2Elab Grenoble, France V Atrazhev, Joint Institute for High Temperatures, Russia

V.A. Shakhatov, Topchiev of Petrochemical Synthesis Institute, RussiaJ. Eloranta Department of Chemistry,California State University, USA

K. von Haeften , Leicester University, Leicester, UK

G Vermeulen, Institut Néel Grenoble, France

22

Corona discharge in dense helium

Liquide

Light emission

Transport zone : E ~ kV/cm µe and µ+

Ionization zone : Ep~ MV/cm

Densities of the plasma particles (Ne and Np), Temperature, etc

2

Crucial importance for the modelling of plasmas produced by electric discharges

I ~ 0.1-50µA, DC V ~ kV

Applied power : 0.5-100mW

gap distance~mm

Rp ~ 0.1-0.2µm

Gas pressure ~ 1-100 bar

CCD Camera picture

Shape of atomic line 706 nm for different states of cryogenic Helium in a cell

0,0

0,2

0,4

0,6

0,8

1,0

1,2

"Red wings"

706.5nm

0.1MPa 0.6MPa 1MPaLiquid He

T=4,2KPositive

Inte

nsi

ty a

rb.u

nit

s

695 700 705 710 7150,0

0,2

0,4

0,6

0,8

1,0

"Blue wings"

706.6nm

Inte

nsity

, arb

.uni

ts.

Wavelength, nm.

NegativeT=5.1KGas

0.2MPaLiquid

0.7MPa 1.2MPa

POSITIVE NEGATIVE

Plane

e-e-

e-

- ---

e-e-

e-

+

Plane

+++

He+

He+

He+