Runaway electrons, accelerated in a tokamak discharge to high energies (tens of MeV), can cause serious damage to plasma facing components. Therefore, it is important to develop effective mitigation strategies to reduce the risk of tokamak damage. To study the effects of various mitigation strategies, a dedicated diagnostic, the calorimetry probe, was developed at the COMPASS tokamak. This probe successfully measured the heat loads caused by runaway electrons directly, using a set of temperature sensors embedded in a graphite body. Deposited energy measured by the probe ranged from a few hundred joules up to (15 ± 1) kJ, while the mean deposited energy was (4.5 ± 1.1) kJ. The design of the probe and the initial results from 250 discharges covering four experimental campaigns dedicated to runaway electron studies (2019–2021) are presented in this article.

1.
J.
Martin-Solis
,
A.
Loarte
,
E.
Hollmann
,
B.
Esposito
,
V.
Riccardo
,
FTU
,
DIII-D Teams
, and
JET EFDA Contributors
,
Nucl. Fusion
54
,
083027
(
2014
).
2.
E.
Hollmann
,
G.
Arnoux
,
N.
Commaux
,
N.
Eidietis
,
T.
Evans
,
R.
Granetz
,
A.
Huber
,
D.
Humphreys
,
V.
Izzo
,
A.
James
et al,
J. Nucl. Mater.
415
,
S27
(
2011
).
3.
V.
Weinzettl
,
J.
Adamek
,
M.
Berta
,
P.
Bilkova
,
O.
Bogar
,
P.
Bohm
,
J.
Cavalier
,
R.
Dejarnac
,
M.
Dimitrova
,
O.
Ficker
et al,
J. Instrum.
12
,
C12015
(
2017
).
4.
U.
Sheikh
,
J.
Decker
,
M.
Hoppe
,
M.
Pedrini
,
B.
Sieglin
,
L.
Simons
,
J.
Cazabonne
,
J.
Caloud
,
J.
Cerovsky
,
S.
Coda
et al,
Plasma Phys. Controlled Fusion
66
,
035003
(
2024
).
5.
G.
Matthews
,
B.
Bazylev
,
A.
Baron-Wiechec
,
J.
Coenen
,
K.
Heinola
,
V.
Kiptily
,
H.
Maier
,
C.
Reux
,
V.
Riccardo
,
F.
Rimini
et al,
Phys. Scr.
2016
,
014070
.
6.
M.
Forster
,
K.
Finken
,
M.
Lehnen
,
J.
Linke
,
B.
Schweer
,
C.
Thomser
,
O.
Willi
,
Y.
Xu
, and
TEXTOR Team
,
Nucl. Fusion
51
,
043003
(
2011
).
7.
T.
Kudyakov
,
K.
Finken
,
M.
Jakubowski
,
M.
Lehnen
,
Y.
Xu
,
B.
Schweer
,
T.
Toncian
,
G.
Van Wassenhove
,
O.
Willi
, and
TEXTOR Team
,
Nucl. Fusion
48
,
122002
(
2008
).
8.
M.
Forster
,
K.
Finken
,
M.
Lehnen
,
O.
Willi
,
Y.
Xu
, and
TEXTOR Team
,
Phys. Plasmas
19
,
052506
(
2012
).
9.
R.
Panek
,
J.
Adámek
,
M.
Aftanas
,
P.
Bílková
,
P.
Böhm
,
F.
Brochard
,
P.
Cahyna
,
J.
Cavalier
,
R.
Dejarnac
,
M.
Dimitrova
et al,
Plasma Phys. Controlled Fusion
58
,
014015
(
2016
).
10.
A.
Havranek
,
V.
Weinzettl
,
D.
Fridrich
,
J.
Cavalier
,
J.
Urban
, and
M.
Komm
,
Fusion Eng. Des.
123
,
857
(
2017
).
11.
J.
Cerovsky
,
O.
Ficker
,
V.
Svoboda
,
E.
Macusova
,
J.
Mlynar
,
J.
Caloud
,
V.
Weinzettl
,
M.
Hron
et al,
J. Instrum.
17
,
C01033
(
2022
).
12.
M.
Berger
,
J.
Coursey
,
M.
Zucker
, and
J.
Chang
, “
Stopping-power and range tables for electrons, protons, and helium ions
,” NIST Standard Reference Database 124,
2017
.
13.
G.
Battistoni
,
T.
Boehlen
,
F.
Cerutti
,
P. W.
Chin
,
L. S.
Esposito
,
A.
Fassò
,
A.
Ferrari
,
A.
Lechner
,
A.
Empl
,
A.
Mairani
et al,
Ann. Nucl. Energy
82
,
10
(
2015
).
14.
CERN
, Fluka 4-4.1, https://fluka.cern,
2024
.
15.
V.
Sizyuk
and
A.
Hassanein
,
Nucl. Fusion
49
,
095003
(
2009
).
16.
COMSOL AB
, Comsol Multiphysics® v. 5.6,
Stockholm, Sweden
, www.comsol.com.
17.
P.
Vondrácek
,
J.
Horácek
,
R.
Pánek
, and
E.
Gauthier
, in
WDS (Matfyzpress
,
2014
), Vol.
14
, pp.
227
232
.
18.
J.
Horacek
,
R.
Pitts
,
J.
Adamek
,
G.
Arnoux
,
J.
Bak
,
S.
Brezinsek
,
M.
Dimitrova
,
R. J.
Goldston
,
J.
Gunn
,
J.
Havlicek
et al,
Plasma Phys. Controlled Fusion
58
,
074005
(
2016
).
19.
B.
Bazylev
,
G.
Arnoux
,
S.
Brezinsek
,
Y.
Igitkhanov
,
M.
Lehnen
,
V.
Riccardo
,
V.
Kiptily
et al,
J. Nucl. Mater.
438
,
S237
(
2013
).
20.
O.
Ficker
,
J.
Mlynar
,
M.
Vlainic
,
J.
Cerovsky
,
J.
Urban
,
P.
Vondracek
,
V.
Weinzettl
,
E.
Macusova
,
J.
Decker
,
M.
Gospodarczyk
et al,
Nucl. Fusion
57
,
076002
(
2017
).
21.
J.
Adamek
,
J.
Seidl
,
J.
Horacek
,
M.
Komm
,
T.
Eich
,
R.
Panek
,
J.
Cavalier
,
A.
Devitre
,
M.
Peterka
,
P.
Vondracek
et al,
Nucl. Fusion
57
,
116017
(
2017
).
22.
J.
Mlynar
,
O.
Ficker
,
E.
Macusova
,
T.
Markovic
,
D.
Naydenkova
,
G.
Papp
,
J.
Urban
,
M.
Vlainic
,
P.
Vondracek
,
V.
Weinzettl
et al,
Plasma Phys. Controlled Fusion
61
,
014010
(
2018
).
23.
O.
Ficker
,
E.
Macusova
,
J.
Mlynar
,
D.
Bren
,
A.
Casolari
,
J.
Cerovsky
,
M.
Farnik
,
O.
Grover
,
J.
Havlicek
,
A.
Havranek
et al,
Nucl. Fusion
59
,
096036
(
2019
).
24.
M.
De Angeli
,
P.
Tolias
,
S.
Ratynskaia
,
D.
Ripamonti
,
L.
Vignitchouk
,
F.
Causa
,
G.
Daminelli
,
B.
Esposito
,
E.
Fortuna-Zalesna
,
F.
Ghezzi
et al,
Nucl. Fusion
63
,
014001
(
2022
).
25.
P.
Vondracek
,
R.
Pánek
,
M.
Hron
,
J.
Havlicek
,
V.
Weinzettl
,
T.
Todd
,
D.
Tskhakaya
,
G.
Cunningham
,
P.
Hacek
,
J.
Hromádka
et al,
Fusion Eng. Des.
169
,
112490
(
2021
).
26.
Y.
Corre
,
G.
Laffont
,
C.
Pocheau
,
R.
Cotillard
,
J.
Gaspar
,
N.
Roussel
,
M.
Firdaouss
,
J.-L.
Gardarein
,
D.
Guilhem
, and
M.
Missirlian
,
Rev. Sci. Instrum.
89
,
063508
(
2018
).
27.
J.
Caloud
,
E.
Tomesova
,
V.
Balner
,
O.
Bogár
,
Y.
Corre
,
R.
Dejarnac
,
M.
Dimitrova
,
J.
Gerardin
,
M.
Hron
,
R.
Pánek
et al,
Fusion Eng. Des.
193
,
113608
(
2023
).
You do not currently have access to this content.