pke-nefedov symposium - 2004

PKE-Nefedov Symposium - 2004

Institute for High Energy Densities of RAS

Optical Diagnostics of Discharge Plasma

in PK-4 Project

Alexander Usachev


1. Diagnostics of concentrations of excited neon atoms.

2. Developing of combined diagnostic probe-optic methods.

3. Control of plasma impurities.

Objectives:

Optical Diagnostics of Plasma in PK-4 Project

Spectral Diagnostics

Glow Image Diagnostics



Glow Image Diagnostics

Phantom-5 = 1


300 350 400 450

0

0.2

0.4

0.6

0.8

1

The spectral transmittance of the PK4-chamber glass.


0

0

000

)()(

~

eeeek

keek

df

NNZ

Emission Intensity of Ne

0

ik

ekNe NNI ~~

In the case of Te= const,

Intensity vs Electron Density in DC-mode

-10 0 10PK-4 Tube R adius, m m

0

200

400

600

800

Ima

ge

In

ten

sity

, a.

u.

0

1

2

3

4

5

Ele

ctro

n D

en

city

, 1

08

cm-3250 Pa

15 Pa

100 Pa


mm

Scale

Ne:50 Pa


Intensity vs Electron Density in DC/RF(i)-mode

-10 -5 0 5 10H , cm

0

4

8

12

16

n e, 1

08 cm

-3, T

e, e

V,

Iin

t, ar

b. u

.

n eTe

In tensity

Intensity Distribution in 2RF(i)-mode


Temporal Behavior of DC Discharge20000 fps 20 fps

10 Pa

50 Pa

300 Pa

Spectral Diagnostics:

1. Emission spectroscopy: measurements of concentration of highly excited neon atoms.

2. Absorption spectroscopy: measurements of concentration of metastable and resonance neon atoms.

3. Emission spectroscopy: control of plasma impurities.


Emission spectroscopy: measurements of concentration of highly excited neon atoms

by the method of absolute intensities



Emissive spectrum of Ne in DC discharge: 3 mA; 50 Pa.

500 550 600 650 700 750 800W avelength, nm

0

2

4

6

8

10

300 350 400 450 500W avelength, nm

0

2

4

6

8

10

2p 1s

3p 1s


22121 NhvAP

Emission spectroscopy: measurements of concentration of highly excited neon atoms

by the method of absolute intensities

Absolute concentrations of 2p and 3p levels of neonin RF(i) discharge at 10, 100 and 1000 Pa.


1 8 1 8 . 5 1 9 1 9 . 5 2 0 2 0 . 5 2 1

E , eV

1e+004

1e+005

1e+006

1e+007

1e+008

N/g

, c

m-3

2p-levels

3p-levels

1000 Pa

100 Pa

10 Pa


Local Thermal Equilibrium of 2p-levels of Neonin RF(i) discharge at 10, 100 and 1000 Pa

18.3 18.4 18.5 18.6 18.7 18.8 18.9

E, eV

1e+005

1e+006

1e+007

1e+008

N/g

, cm

-3

0.21 eV

0.42 eV

0.55 eV

Tn = 0.026 eV

Te = 3 eV

p=1000 Pa

p=100 Pa

p=10 Pa


Absorption spectroscopy: measurements of concentration of metastable and resonance

neon atoms by the method of one mirror.

Spectrometertranslation

High voltage CM SM

CM

PMT

C

Lens

PK4 chamber

Mirror

Chopper

PC


Measurements of concentration of metastable and resonance neon atoms by the method of one mirror.


Typical Spectrogram.

626 628 630 632 634

W avelength, nm

0

1

2

3

Inte

nsity

, a.

u.

U2

U1

RU

U

lk

eff

11ln

1

1

2

R=0.92

112

2

0

2ln2Nf

cm

ek

eD

For Doppler shape of line:


16.6 16.65 16.7 16.75 16.8 16.85

E 1, eV

2e+009

4e+009

6e+009

8e+009

1e+010

N1

/ g1

,

cm-3

1 m A , 50 Pa

16.6 16.65 16.7 16.75 16.8 16.85

E 1, eV

1e+008

1e+009

1e+010

N1 /

g 1 ,

cm

-3

5 m A, 50 Pa

16.6 16.65 16.7 16.75 16.8 16.85

E 1, eV

1e+008

1e+009

1e+010

N1

/ g1

,

cm-3

15 m A , 50 P a

IDC = 1 mA

IDC = 5 mA

IDC = 15 mA

Population of 1s-Levels vs Direct Current (at 50 Pa)


0 4 8 12 16

IDC , m A

0

1e+010

2e+010

3e+010

N3S

, cm

-3

Total Density of Ne-3S Atoms vs Direct Current

4

13

iiiS NgN


Population of 1s Levels vs Ne Pressure

16.6 16.65 16.7 16.75 16.8 16.85E 1, eV

1e+008

1e+009

1e+010N

1/ g

1, c

m-3

12 Pa, 15 m A

16.6 16.65 16.7 16.75 16.8 16.85E 1, eV

1e+008

1e+009

1e+010

N1/

g1,

cm

-3

25 Pa, 15 m A

16.6 16.65 16.7 16.75 16.8 16.85E 1, eV

1e+008

1e+009

1e+010

N1/ g

1, c

m-3

50 P a, 15 m A

16.6 16.65 16.7 16.75 16.8 16.85E 1, eV

1e+008

1e+009

1e+010

N1/

g1,

cm

-3

100 Pa, 15 m A

p = 12 Pa

p = 25 Pa p = 100 Pa

p = 50 Pa

m m rm m rr

m m rrm m rr


Emission spectroscopy -Diagnostics of Gas Mixtures:

1. Ne + 2%Xe.

2. Ne + O2.

3. Ne + Air Leakage.


300 400 500 600 700

W avelength, nm

0

2

4

6

8

10

Intensity, a.u.

300 400 500 600 700

W avelength, nm

0

2

4

6

8

10

Intensity, a.u.

Emission Spectra of pure Ne and Ne+2%Xe-mixture

50 Pa of Ne, 3 mA_433V

50 Pa of Ne+2%Xe, 3 mA_400V

Ne(2p 1s)

Xe(2p 1s)


Reference Spectra of Pollutants: O2 and N2

200 300 400 500 600 700 800

nm

0

2

4

6

8

10

200 300 400 500 600 700 800

nm

0

0.4

0.8

1.2

1.6

2

H

O2

N2


UV Reference Spectra of Pollutants: O2 and N2

O2

N2

300 320 340 360 380 400

nm

0

0.4

0.8

1.2

1.6

2

300 320 340 360 380 400

nm

0

2

4

6

8

10

Used O2-band


OH Spectra of Pollutant H2O

OH

300 310 320 330

0

0.1

0.2

0.3

0.4

0.5

N e (10atm )

300 310 320 330

W avelength, nm

0

0.1

0.2

0.3

0.4

0.5

Intensity, a.u.

N e: N ew _ Ballon 150atm2200V , 50/50m km

Old Ne balloon

New Ne balloon

N2

N2

Emission Spectra of pure Ne and Ne+0.05%O2, Ne+0.15%O2 -mixtures

300 320 340 360 380 400

W avelength, nm

0

1

2

3

4

Inte

nsity

, a.

u.


320 324 328 332 336 340

W avelength, nm

0

0.05

0.1

0.15

0.2

0.25

Inte

nsity

, a.

u.


300 320 340 360 380 400

W avelength, nm

0

1

2

3

4

Inte

nsity

, a.

u.

N e + 0.15O 22200V , 50/50m km

320 324 328 332 336 340

W avelength, nm

0

0.05

0.1

0.15

0.2

0.25

Inte

nsity

, a.

u.

N e + 0.15O 22200V , 50/50m km

300 320 340 360 380 400

W avelength, nm

0

1

2

3

4

Inte

nsity

, a

.u.

N e + 0.05O 22200V , 50/50m km

320 324 328 332 336 340

W avelength, nm

0

0.05

0.1

0.15

0.2

0.25

Inte

nsity

, a.

u.

N e + 0.05O 22200V , 50/50m km

Ne Ne+0.05%O2 Ne+0.15%O2


O2-bandO2-band

N2-band N2-bandN2-band


Comparison of Spectroscopic and Probe Datafor Ne, Ne+0.05%O2 and Ne+0.15%O2 -mixtures

0 0.05 0.1 0.15

0

1

2

3

4

5

Spe

ctra

l Int

ensi

ty,

a.u.

0

4

8

12

Ele

ctro

n de

ncity

, 10

7 cm

-3

E

INe

ne

IO2


320 330 340 350

0

1

2

3

4

5

nn0

320 330 340 350

0

1

2

3

4

5

nn1

320 330 340 350

0

1

2

3

4

5

nn2

320 330 340 350

0

1

2

3

4

5

nn3

320 330 340 350

0

1

2

3

4

5

nn4

320 330 340 350

0

1

2

3

4

5

nn5

Spectral Intensities of Ne, N2 and O2 vs Air Addition

NeNe

Ne

NeNe

NeO2 O2

N2

N2N2

N2

N2

N2


0 0.01 0.02 0.03

Volum e part o f A ir

0

40

80

120

Spe

ctra

l Int

ensi

ty,

a. u

.Comparison of Spectral and Probe Data Drifts at Air Leakage

0 0.005 0.01 0.015 0.02 0.025

Partia l A ir P ressure in N e

0

2

4

6

8

10

E,

ne,

T

e

E

n e, 1m A

n e, 3m A

T e

O210

Ne

N2


1..

2..

3..

Conclusion:

Thank you for your attention

pke-nefedov symposium - 2004

Documents

high energy densities

high energy densities

high energy densities

excited neon atoms

resonance neon atoms

ne o2

measurements of concentration

433v50 pa of ne