1. Branch of JSC URSC – ISDE, Russian Federation
12th GEANT4 Space Users Workshop
10-12 April, 2017
University of Surrey, Guildford, Surrey, UK
GEANT4 implementation at Roscosmos SEE test facilities based on ion sources and at material’s shielding properties determination
Grigory Protopopov
Branch of JSC URSC – ISDE, Russian Federation

2. The Branch of URSC – ISDE and The Test Laboratory for Hardness to Radiation Effects
The Branch of URSC – ISDE is a coordinator of Roscosmos activities which cover the creation and introduction of manufacturing methods for radiation hardness control, including:
Function implementations as a head company of the Russian Inter-agency Component Radiation Testing Center from the Roscosmos side
Creation and operation covering of testing aids:
•  Test facilities (heavy ion, proton and neutron (SEE, DD), gamma, laser)
•  Standards and guidelines
•  Software
Creation and operation covering of the Database for Components and Systems
Creation and operation covering of the Space Radiation exposure on electronic components Monitoring System
Scientific and technical conferences co-organization
The official websites are

3. Technical Features of the SEE Test Facilities based on ion sources [1, 2]
IS OI (400)/ IS KOE
BIS OI-A (400М)/ IS OE PP
IS OE VE
IS OU 400-N
Ion source
Cyclotron U-400/ U-400М FLNR JINR
Cyclotron U-400М FLNR JINR
Cyclotron U-400 FLNR JINR
Energy, MeV/nucleon
3 .. 6/ 9
3 .. 6
(60 for light ions)
Flux density, particle/(cm2 × s)
Nonuniformity, %
± 15
± 10
Suit of ions
C, Ne, Ar, Fe, Kr, Xe, Bi
C, O, Ne, Ar, Fe, Kr, Xe, Bi
Ne, Ar, Kr, Xe (O, Fe, Bi)
Ne, Ar, Kr, Xe
LET (Si), MeV × cm2/mg
(with using degraders)
Range in Si, μm
>30
> 30
Irradiation area, mm
100 х 100
100 х 100/ 200 х 200
Ø 50
150 х 200
Operational pressure, Pa
2,2 х 10-3
Forvacuum/atmosphere
Chargeover time for gaseous ion, hour 8
8/ 6 6
Chargeover time for metal ion, hour 24
24/ 18 18
Vacuum pumping time, min
8/ 10
10/ 6 5
Temperature range, °С
+25/

4. Ion’s parameters determination
Ion’s parameters determination methods
Technical features
Low energy facility
High energy facility
Ion’s energy in vacuum channel
Measurements by time-of-flight method
Ion’s energy at DUT
Calculation *
Ion’s LET
Ion’s range
* Calculations using different software, including GEANT4

5. Inputs for calculation’s results comparing
Goal: Determination of ion’s energetic characteristics at DUT behind degraders using different software (including GEANT4, SRIM and other similar software)
Inputs:
Ion (energy, MeV/n)
Degraders (material, thickness)
1st layer*  
2nd layer**
3rd layer***
Ar (34)
Stainless steel
Ni, 100 um
Forevacuum
Air
Kr (30)
Al, 40 um
Xe (25)
Al, 180 um
Bi (15)
Al, 35 um
* Stainless steel: Fe - 74%, Cr - 8%, 58.69Ni - 18%, density 8.0 g/cm3
** 58.69Ni (8.9 g/cm3) or 27Al (2.7 g/cm3)
*** 1 atm ( *10-3 g/cm3) or 10 torr (forevacuum, 1/76 atm, *10-5 g/cm3)

6. Variation of calculation results
Variation of calculation results (average ion’s energy, LET and range) using different software (and physics)
Energy
LET
Range
Ion (energy, MeV/n)
Maximal variation
Average variation, %
Ar (34)
1.05
1.7
1.03
1.2
1.07
2.7
1.09
1.06
1.9
1.14
4.2
Kr (30)
1.11
3.8
2.3
1.16
5.0
Xe (25)
3.03 41
1.15
5.3
2.50 35
Bi (15)
1.34
9.7
1.04
1.5
1.28
7.3
Maximal variation is observed for Xe (great drop of energy) for SRIM and GEANT4 calculations (depending on physics)
Calculation results for different GEANT4 physics can vary in several times
Experimental verification is needed (it is planned in future work)

7. Consideration of secondary ions during radiation test
Primary ions (passing through the degrader) produce secondary ions which can influence on radiation test results
LETprim < LETsec
No influence
Lth < Lprim < Lsec
Influence
Lprim < Lth < Lsec

8. Calculation results for secondary ions characteristics
GEANT4 calculation of secondary ions which are produced by 106 primary ions (Ar, 1380 MeV) passing through Ni plate 0.1 mm
Average energy of primary Ar - ~1020 MeV (average LET - ~5.3 MeV*cm2/mg)
Average energy of secondary Ni - ~280 MeV (average LET - ~27 MeV*cm2/mg)
Recommendation: if possible, to use “light” material as a degrader (Al, not Ni)

9. Material’s radiation-shielding properties determination. Experiment [3]
Thermal control coating with high-Z components (2 types)
Experiments at electrons accelerators (2 energies)
Energy of electrons was determined using a criterion of the best match of experimental and calculated (GEANT4) absorbed dose profile data
Electron beam
TLD
Experiment geometry

10. Material’s radiation-shielding properties determination
Material’s radiation-shielding properties determination. Experimental and calculation results of electron dose attenuation by TCC [3]
Discrepancy.:
<15% (1.86 MeV)
Discrepancy.:
<30% (3.7 MeV)
TCC is more effectively (in ~30%) in real conditions than an equivalent aluminum (GEANT4 calculations)

11. Experimental and calculation (GEANT4) results show a good agreement
Conclusions …
GEANT4 is widely used to determine ion’s energetic characteristics at Roscosmos SEE test facilities and material’s shielding properties
Experimental and calculation (GEANT4) results show a good agreement

12. ion’s energy behind the shield (E<10 GeV)
… and questions
What is the reason of variation of calculation results (average ion’s energy behind degraders) using different physics?
What are recommendations for physics implementation for following calculations:
ion’s energy behind the shield (E<10 GeV)
In-orbit absorbed dose (including secondary gamma)
Secondary ions (produced by primary protons and ions)
Radiation-Induced charge (including methods)

13. References
Compendium of international irradiation test facilities th European Conference on Radiation and Its Effects on Components and Systems (RADECS)
V. S. Anashin, A. E. Koziukov, L. R. Bakirov, T. A. Maksimenko, A. I. Ozerov, G. A. Protopopov, and P. A. Chubunov, “Typical Facilities and Procedure for Single Event Effects Testing in Roscosmos,” th European Conference on Radiation and Its Effects on Components and Systems (RADECS) Radiation Effects Data Workshop (REDW), Sep
V. S. Anashin, G. A. Protopopov, O. S. Kozyukova, I. A. Lyakhov, V. F. Zinchenko, A. V. Grigorevskiy, R. H. Khasanshin, and A. V. Sogoyan, “The Experimental and Simulation Study of Specialized Thermal Control Coating Application for Radiation Shielding of Electronic Components,” th European Conference on Radiation and Its Effects on Components and Systems (RADECS), Sep

14. Acknowledgment
I thank my colleagues: Lyakhov I., Rukavichnikov S. et al.

15. 14-15 of June in S.Peterburg, AZIMUT Hotel e-mail: info@radtest.ru.com
RAD-TEST 2017 Workshop, which is organized by the Branch of “URSC”-”ISDE” under the authority of RADECS Association
14-15 of June in S.Peterburg, AZIMUT Hotel
Workshop subjects:
methodology of components and systems radiation hardness assurance, procedural guidelines,
practical aspects of component and system radiation tests, which help to increase its reliability and reduce costs,
features of component hardness assurance in modern technologies,
technological features of component radiation hardness assurance tests, usage pattern of simulation test facilities,
feature-based inspection for objects and effects during tests,
field transformation calculation problems (and during tests) when they interact with components, systems and materials; software, radiation measurement characteristics, types of detectors, etc.
direction for the development of hardness assurance methods and facilities

16. Thank you for your attention!

17. ion’s energy behind the shield (E<10 GeV)
… and questions
What is the reason of variation of calculation results (average ion’s energy behind degraders) using different physics?
What are recommendations for physics implementation for following calculations:
ion’s energy behind the shield (E<10 GeV)
In-orbit absorbed dose (including secondary gamma)
Secondary ions (produced by primary protons and ions)
Radiation-Induced charge (including methods)