1. Multispacecraft observation of solar particle events contribution in the space radiation exposure on electronic equipment at different orbits
Vasily S. Anashin1, Grigory A. Protopopov1, Igor A. Lyakhov1,
Sergey O. Rukavichnikov1, Pavel V. Shatov2
1 Branch of JSC URSC ISDE
2 FSBI Fedorov Institute of Applied Geophysics

2. Content
Introduction
List of spacecrafts and onboard sensors’ parameters
SPE spectra in GSO, polar, MEO and LEO (experiment and calculation)
Absorbed doses in MEO and LEO (experiment and calculation)
SER in GSO, polar, MEO and LEO (calculation)
Conclusions

3. Influence of space radiation environment, include SCR, on electronic component
Space radiation environment is the main exposure factor which determines the active shelf life of spacecrafts: faults and failures due to space radiation exposure were observed in ~60% space missions*
Dose effects
Trapped electrons (only near-Earth missions)
Trapped protons (only near-Earth missions)
Solar protons
GCR (only for interplanetary missions)
Single event effects
Trapped protons
Solar protons and ions
Protons and ions of GCR
*Committee on the Societal and Economic Impacts of Severe Space Weather events: A Workshop Report, 2008

4. List of spacecrafts and onboard sensors’ parameters
GOES (GSO)*
Protons: >1, >10, >100 MeV
Electro-L (GSO)
Protons: , 23-42, MeV
Spacecrafts in MEO
Absorbed dose measurements
Meteor-M (polar)
Protons and electrons: >15 and >0.7 MeV, >25 and >1.5 MeV, >600 and >6 MeV
ISS (LEO) *

5. SPE spectra in GSO according GOES and Electro-L measurements. Event 1

6. SPE spectra in GSO according GOES and Electro-L measurements. Event 2

7. SPE spectra in GSO according GOES and Electro-L measurements. Event 3

8. Determination of SPE spectra in polar orbit
Meteor-M data
SEP contribution – in polar regions mainly (in the maximum L)

9. SPE spectra determination results for polar orbit. Events 1-3
1) ) )

10. Calculation of SPE spectra in MEO and LEO
Inputs: SPE spectrum in GSO
Consideration of geomagnetic cutoff rigidity
For average annual Kp (2-3)
More careful Rg consideration leads to shifting of low-energetic part of SPE spectrum (future work)
FMEO(E)=FGSO*coefficient

11. SPE spectra calculation results for MEO. Events 1-3
1) ) )

12. SPE spectra calculation results for LEO. Events 1-3
1) ) )

13. Calculation of absorbed doses in MEO and LEO
Inputs:
SPE spectrum in the given orbit
Shielding geometry
Calculation using OMERE software* *
Benghin V.V et al. Scientific Session MEPhI-2015

14. Absorbed dose. Experimental and calculation results. MEO
Event
Experimental*, a.u./day
Calculation**, a.u./day
8.5
3.9
8.7
1.5 90
3.6
* Total value (electron+protons)
** SPE dose
Annual dose: 143 a.u./day
Max dose: 1900 a.u/day
Discrepancy can be concerned with:
Electrons exposure influence on experimental absorbed dose value
Gap in data

15. Absorbed dose. Experimental and calculation results. LEO
Event
Experimental*, a.u./day
Calculation**, a.u./day
143
1840
769 (> 100 MeV)
202
269
56 (> 100 MeV)
154
125
117 (> 100 MeV)
* Differential of total values during events and a week before
** SPE dose
Annual dose: ~27 a.u./day
GCR dose: ~9 a.u./day
Max dose: 226 a.u/day
Discrepancy can be concerned with:
Inaccuracy of SPE absorbed dose determination
Inaccuracy of SPE spectra determination
Consideration average annual Kp
Inaccuracy of shielding determination
Gap in data

16. SPE contribution in the space radiation exposure on electronic equipment at different orbits
MEO:
The main contribution: trapped electrons (dose per day values during the events are comparable with mean value for a long time, but dose peak value is more in orders of magnitude)
SPE gives valuable dose in absence of high-energy electrons flux increasing
LEO:
The main contribution: trapped protons, SEP and GCR (dose per day values during the events are comparable (and sometimes more) with mean value for a long time and dose peak value)
SPE gives valuable dose (not all events)

17. Single event rates caused by SPE exposure in different orbits
SER*
GSO
MEO
polar
LEO
Event1
11.3
6.0
8.6
0.86
Event2
9.7
5.1
3.7
0.74
Event3 53 28
7.5
4.1
Number of SEU (SER) during event
E0=10 MeV
σsat=0.01 cm2
1 bit
SER from SCR is decreasing with decreasing of altitude (geomagnetic cut-off rigidity)
SER varies for event to event (several times)
SPE contribute decisively in SER in GSO and MEO (absence of trapped protons)
SPE gives valuable contribution in SER in polar orbit and LEO

18. Conclusions
SEP fluxes for different events in 2012 were determined using onboard measurements in different spacecrafts and calculated for MEO and LEO
Doses from SEP were calculated and compared with onboard measurements
SPE gives valuable dose in LEO and MEO, which is comparable with average dose value (during absence of high-energy electrons flux increasing in MEO)
SPE contribute decisively in SER in GSO and MEO and gives valuable contribution in polar orbit and LEO
It is necessary (for spacecraft and equipment manufacturers as well as for scientific community) to place space radiation characteristics and exposure sensors on spacecrafts in different orbits

19. Acknowledgement
Pavel Shatov (Fedorov Institute of Applied Geophysics)
Vyacheslav Shurshakov (Institute for Biomedical Problems)
Andrey Lishnevskii (Institute for Biomedical Problems)
Viktor Benghin (Institute for Biomedical Problems, Skobeltsyn Institute of Nuclear Physics of MSU)

20. Thank you for your attention. Grazie. NPK1@NIIKP
Thank you for your attention! Grazie! Grigory protopopov