The plasma-induced magnetic field in an electron cyclotron resonance plasma thruster is measured non-intrusively by means of a diamagnetic loop that encloses the plasma flow. The calibration process is described, and parasitic currents in the thruster walls and plasma oscillations are identified as the dominant sources of uncertainty. The integrated magnetic flux is seen to depend on the applied power and less significantly on the mass flow rate. The effect of the diamagnetic loop radius is also studied by testing two loops of different diameters. To estimate the perpendicular electron pressure in the plasma from the loop measurements, two plasma beam models, 1D and 2D, are used. While both models give similar results for the small loop, they differ significantly for the large loop, showing the relevance of 2D effects when a large diamagnetic loop is used.

1.
E. F.
Gibbons
and
D. B.
Miller
, “
Experiments with an electron cyclotron resonance plasma accelerator
,”
AIAA J.
2
(
1
),
35
41
(
1964
).
2.
M.
Nagatomo
, “
Plasma acceleration by high frequency electromagnetic wave in staticmagnetic field gradient
,” in
6th Electric Propulsion and Plasmadynamics Conference
(American Institute of Aeronautics and Astronautics, September
1967
), p.
660
.
3.
J.
Sercel
, “
Electron-cyclotron-resonance (ECR) plasma thruster research
,” in
24th Joint Propulsion Conference
(American Institute of Aeronautics and Astronautics, July
1988
), p.
2916
.
4.
E.
Bickford Hooper
,
B. W.
Stallard
, and
M. A.
Makowski
, “
Whistler wave driven plasma thruster
,”
AIP Conf. Proc.
271
,
1419
1424
(
1993
).
5.
J.
Jarrige
,
P.-Q.
Elias
,
D.
Packan
, and
F.
Cannat
, “
Characterization of a coaxial ECR plasma thruster
,” in
44th AIAA Plasmadynamics and Lasers Conference
(American Institute of Aeronautics and Astronautics, June
2013
), p.
2628
.
6.
C.
Charles
and
R.
Boswell
, “
Current-free double-layer formation in a high-density helicon discharge
,”
Appl. Phys. Lett.
82
(
9
),
1356
1358
(
2003
).
7.
D.
Pavarin
,
F.
Ferri
,
M.
Manente
,
D.
Curreli
,
Y.
Guclu
,
D.
Melazzi
,
D.
Rondini
,
S.
Suman
,
J.
Carlsson
,
C.
Bramanti
 et al, “
Design of 50 W helicon plasma thruster
,” in
31st International Electric Propulsion Conference
, Ann Arbor, MI,
2009
, pp.
2009
2205
.
8.
J.
Navarro-Cavallé
,
M.
Wijnen
,
P.
Fajardo
, and
E.
Ahedo
, “
Experimental characterization of a 1 kW Helicon plasma thruster
,”
Vacuum
149
,
69
73
(
2018
).
9.
E.
Ahedo
and
M.
Merino
, “
Two-dimensional supersonic plasma acceleration in a magnetic nozzle
,”
Phys. Plasmas
17
(
7
),
073501
(
2010
).
10.
M.
Merino
and
E.
Ahedo
, “
Magnetic nozzles for space plasma thrusters
,”
Encyclopedia of Plasma Technology
, edited by
J. L.
Shohet
(
Taylor and Francis
,
2016
), Vol.
2
, pp.
1329
1351
.
11.
M.
Merino
and
E.
Ahedo
, “
Plasma detachment in a propulsive magnetic nozzle via ion demagnetization
,”
Plasma Sources Sci. Technol.
23
(
3
),
032001
(
2014
).
12.
M.
Merino
and
E.
Ahedo
, “
Effect of the plasma-induced magnetic field on a magnetic nozzle
,”
Plasma Sources Sci. Technol.
25
(
4
),
045012
(
2016
).
13.
R.
Geller
,
Electron Cyclotron Resonance Ion Sources and ECR Plasmas
(
CRC Press
,
1996
).
14.
T.
Vialis
,
J.
Jarrige
, and
D.
Packan
, “
Separate measurements of magnetic and pressure thrust contributions in a magnetic nozzle electron cyclotron resonance plasma thruster
,” in
Space Propulsion Conference
, No. 499, Seville, Spain, May
2018
.
15.
I. H.
Hutchinson
, “
Principles of plasma diagnostics: Second edition
,”
Plasma Phys. Controlled Fusion
44
(
12
),
2603
2603
(
2002
).
16.
W. M.
Hooke
,
M. A.
Rothman
,
J.
Sinnis
, and
J.
Adam
, “
Temperature and power measurements in a plasma heated by absorption of ion cyclotron eaves
,”
Phys. Fluids
8
(
6
),
1146
(
1965
).
17.
K.
Uo
, “
Perpendicular temperature of the C-Stellarator plasma
,”
Phys. Fluids
8
(
2
),
384
(
1965
).
18.
S.
Yoshikawa
,
M. A.
Rothman
, and
R. M.
Sinclair
, “
Absorption of ion cyclotron waves by one component of a two-ion plasma
,”
Phys. Rev. Lett.
14
(
7
),
214
216
(
1965
).
19.
J. C.
Sercel
, “
An experimental and theoretical study of the ECR plasma engine
,” Ph.D. thesis (California Institute of Technology,
1993
).
20.
A.
Ando
,
M.
Inutake
,
K.
Hattori
,
M.
Shibata
, and
Y.
Kasashima
, “
ICRF heating and plasma acceleration with an open magnetic field for the advanced space thruster
,”
Fusion Sci. Technol.
51
(
2T
),
72
74
(
2007
).
21.
C.
Thomas
,
N.
Gascon
, and
M.
Cappelli
, “
Nonintrusive characterization of the azimuthal drift current in a coaxial E cross B discharge plasma
,”
Phys. Rev. E
74
(
5
),
056402
(
2006
).
22.
M.
Prioul
,
A.
Bouchoule
,
S.
Roche
,
L.
Magne
,
D.
Pagnon
,
M.
Touzeau
, and
P.
Lasgorceix
, “
Insights on physics of Hall thrusters through fast current interruptions and discharge transients
,” in
27th International Electric Propulsion Conference
, IEPC-01-059,
2001
.
23.
K.
Takahashi
,
A.
Chiba
,
A.
Komuro
, and
A.
Ando
, “
Experimental identification of an azimuthal current in a magnetic nozzle of a radiofrequency plasma thruster
,”
Plasma Sources Sci. Technol.
25
(
5
),
055011
(
2016
).
24.
B. R.
Roberson
,
R.
Winglee
, and
J.
Prager
, “
Enhanced diamagnetic perturbations and electric currents observed downstream of the high power helicon
,”
Phys. Plasmas
18
(
5
),
053505
(
2011
).
25.
R. L.
Stenzel
and
J. M.
Urrutia
, “
Electron magnetohydrodynamic turbulence in a high-beta plasma. I. Plasma parameters and instability conditions
,”
Phys. Plasmas
7
(
11
),
4450
4456
(
2000
).
26.
C. S.
Corr
and
R. W.
Boswell
, “
High-beta plasma effects in a low-pressure helicon plasma
,”
Phys. Plasmas
14
(
12
),
122503
(
2007
).
27.
J.
Noland
,
O.
Tarvainen
,
J.
Benitez
,
D.
Leitner
,
C.
Lyneis
, and
J.
Verboncoeur
, “
Studies of electron heating on a 6.4 GHz ECR ion source through measurement of diamagnetic current and plasma bremsstrahlung
,”
Plasma Sources Sci. Technol.
20
(
3
),
035022
(
2011
).
28.
J.
Booske
,
M.
McCarrick
,
S.
Douglass
,
J.
Paquette
,
R.
Ellis
, and
W.
Getty
, “
Frequency compensation of a diamagnetic loop using a digital data acquisition system
,”
J. Phys. E: Sci. Instrum.
20
(
6
),
627
(
1987
).
29.
T.
Vialis
,
J.
Jarrige
,
A.
Aanesland
, and
D.
Packan
, “
Direct thrust measurement of an electron cyclotron resonance plasma thruster
,”
J. Propul. Power
34
(
5
),
1323
1333
(
2018
).
30.
T.
Lafleur
,
F.
Cannat
,
J.
Jarrige
,
P.
Elias
, and
D.
Packan
, “
Electron dynamics and ion acceleration in expanding-plasma thrusters
,”
Plasma Sources Sci. Technol.
24
(
6
),
065013
(
2015
).
31.
S.
Correyero Plaza
,
J.
Jarrige
,
D.
Packan
, and
E.
Ahedo Galilea
, “
Measurement of anisotropic plasma properties along the magnetic nozzle expansion of an electron cyclotron resonance thruster
,” in
35th International Electric Propulsion Conference
, No. IEPC-2017–437, Electric Rocket Propulsion Society, Fairview Park, OH, Atlanta, GA,
2017
.
32.
M.
Merino
and
E.
Ahedo
, “
Fully magnetized plasma flow in a magnetic nozzle
,”
Phys. Plasmas
23
(
2
),
023506
(
2016
).
33.
M.
Merino
and
E.
Ahedo
, “
Influence of electron and ion thermodynamics on the magnetic nozzle plasma expansion
,”
IEEE Trans. Plasma Sci.
43
,
244
251
(
2015
).
34.
M.
Abramowitz
and
I. A.
Stegun
,
Handbook of Mathematical Functions: With Formulas, Graphs, and Mathematical Tables
(
Courier Corporation
,
1965
), Vol.
55
.
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