Solar Cycle Electron Radiation Environment at GNSS Like Altitude

In April 2001 Mars Odyssey spacecraft with High Energy Neutron Detector (HEND) onboard was launched to Mars. HEND/Odyssey was switched on measurement mode most of transit to Mars to monitor variations of spacecraft background and solar activity. Although HEND/Odyssey was originally designed to measure martian neutron albedo and to search for martian subsurface water/water ice, its measurements during cruise phase to Mars are applicable to evaluate spacecraft ambient radiation background. The biological impact of neutron component of this radiation background should be understood to take it into account in planning future manned missions to Mars. &#160;We modeled spacecraft neutron spectral density and compare it with HEND measurements to estimate equivalent neutron dose rates during Odyssey cruise phase, which corresponds to the solar maxim period (23th solar cycle). It was found that Odyssey ambient neutron environment during May &#8211; September 2001 produces 6.3&#177;1.0 mSv per day in energy range 0-15 MeV or about 23 mSv per day if extrapolated to 0-1000 MeV energy range for sun quiet intervals without Solar Particle Events (SPEs). The occurrence of SPEs may additionally increase the total neutron radiation dose accumulated for 6 months of Odyssey cruise phase up to 10%. We have also extrapolated HEND/Odyssey measurements to the different periods of solar cycle and found that during solar minimum (maximum of GCR flux) neutron equivalent rate during cruise to Mars could be as high as 40 mSv per day.&#160; These values are in good agreement with results reported for a similar measurement made with an instrument aboard the Mars Science Laboratory during its cruise to Mars in 2011-2012.

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Solar cycle variations of MIR radiation environment as observed by the LIULIN dosimeter

Radiation Measurements ◽

10.1016/s1350-4487(99)00061-x ◽

1999 ◽

Vol 30 (3) ◽

pp. 269-274 ◽

Cited By ~ 18

Author(s):

Ts P Dachev ◽

B.T Tomov ◽

Yu N Matviichuk ◽

R.T Koleva ◽

J.V Semkova ◽

...

Keyword(s):

Solar Cycle ◽

Radiation Environment

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Review of charge deposition characteristics and trap parameters of dielectric in space electron radiation environment

Acta Physica Sinica ◽

10.7498/aps.68.20191252 ◽

2019 ◽

Vol 68 (23) ◽

pp. 239401

Author(s):

Guo-Chang Li ◽

Sheng-Tao Li

Keyword(s):

Radiation Environment ◽

Electron Radiation ◽

Charge Deposition

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Radiation environment in the interplanetary space and Mars orbit during the declining phase of 24th solar cycle and transition to 25th cycle according measurements aboard ExoMars TGO

10.5194/egusphere-egu21-2925 ◽

2021 ◽

Author(s):

Jordanka Semkova ◽

Keyword(s):

Solar Cycle ◽

Interplanetary Space ◽

Basic Research ◽

Radiation Environment ◽

Neutron Detectors ◽

Dose Rates ◽

24Th Cycle ◽

National Science ◽

Academy Of Sciences ◽

National Science Fund

Radiation environment in the interplanetary space and Mars orbit during the declining phase of 24th solar cycle and transition to 25th cycle according measurements aboard ExoMars TGOJordanka Semkova1, Rositza Koleva1, Victor Benghin3, Krasimir Krastev1, Tsvetan Dachev1, Yuri Matviichuk1, Borislav Tomov1, Stephan Maltchev1, Plamen Dimitrov1, Nikolay Bankov1, Igor Mitrofanov2, Alexey Malakhov2, Dmitry Golovin2, Maxim Mokrousov2, Anton Sanin2, Maxim Litvak2, Maya Djachkova2, Sergey Nikiforov2, Denis Lisov2, Artem Anikin2, Vyacheslav Shurshakov3, Sergey Drobyshev3&#160;1Space Research and Technology Institute, Bulgarian Academy of Sciences, Sofia, Bulgaria, [email protected]2Space Research Institute, Russian Academy of Sciences, Moscow, Russia,&#160;[email protected]3State Scientific Center of Russian Federation, Institute of Biomedical Problems, Russian Academy of Sciences, Moscow,&#160;Russia,&#160;[email protected]&#160;The dosimetric telescope Liulin-MO for measuring the radiation environment is a module of the Fine Resolution Epithermal Neutron Detector (FREND) onboard the ExoMars TGO.Here we present results from measurements of the charged particle fluxes, dose rates and estimation of radiation quality factors and dose equivalent rates at ExoMars TGO science orbit (circular orbit with 400 km altitude, 740 inclination, 2 hours orbit period), provided by Liulin-MO from May 01, 2018 to January 10, 2021.The obtained data show that: an increase of the dose rates and fluxes is observed from May 2018 to February 2020 which corresponds to the increase of galactic cosmic rays (GCR) intensity during the declining of the solar activity in 24th solar cycle; From March to August 2020 the measured radiation values are practically equal, corresponding to the minimum of 24th cycle and transition to 25th cycle. The highest values of the dose rate (15.5/16.2 &#181;Gy h-1 at two perpendicular directions) and particle flux (3.24/3.33 cm-2s-1 at two perpendicular directions) are registered in this period; Since September 2020 a decrease of the dose rates and fluxes is observed, corresponding to the decrease of GCR intensity during the inclination phase of the 25th cycle.The cosmic ray fluxes and doses measured in Mars orbit are recalculated into values meaningful for the deep interplanetary space at about 1.5 AU. The flux in the free space is at least 3.68 cm-2s-1 and the dose rate is 18.9 &#181;Gy h-1 in August 2020. The results demonstrate that the radiation conditions in the interplanetary space worsen in the minimum of the solar activity in 24th cycle compared to the previous solar minimum.Liulin-MO charged particles measurements are compared for completeness to similar measurements performed by FREND neutron detectors: the instrument&#8217;s 3He neutron detectors are also a source of charged particles flux signal that can be used for correlation.The results are of importance for benchmarking of the space radiation environment models and for assessment of the radiation risk to future manned missions to Mars.AcknowledgementsThe work in Bulgaria is supported by Project No 129 (KP-06 Russia 24) for bilateral projects of the National Science Fund of Bulgaria and Russian Foundation for Basic Research. The work in Russia is supported by Grant 19-52-18009 for bilateral projects of the National Science Fund of Bulgaria and Russian Foundation for Basic Research.

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A solar cycle statistical model for the projection of space radiation environment

Advances in Space Research ◽

10.1016/j.asr.2004.11.036 ◽

2006 ◽

Vol 37 (9) ◽

pp. 1741-1748 ◽

Cited By ~ 17

Author(s):

M.Y. Kim ◽

J.W. Wilson ◽

F.A. Cucinotta

Keyword(s):

Solar Cycle ◽

Statistical Model ◽

Space Radiation ◽

Radiation Environment ◽

Space Radiation Environment

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Induced electron radiation effect on the performance of inter-satellite optical wireless communication

PLoS ONE ◽

10.1371/journal.pone.0259649 ◽

2021 ◽

Vol 16 (12) ◽

pp. e0259649

Author(s):

Abdouraouf Said Youssouf ◽

Nurul Fadzlin Hasbullah ◽

Norazlina Saidin ◽

Mohamed Hadi Habaebi ◽

Rajendran Parthiban ◽

...

Keyword(s):

Wireless Communication ◽

System Level ◽

Radiation Environment ◽

Electron Radiation ◽

Optical Wireless Communication ◽

Optical Wireless ◽

Future Space ◽

Performance Effects ◽

And Performance ◽

The Cost

This paper provides the details of a study on the effects of electron radiation on the Performance of Inters-satellite Optical Wireless Communication (IsOWC). Academia and industry focus on solutions that can improve performance and reduce the cost of IsWOC systems. Spacecraft, space stations, satellites, and astronauts are exposed to an increased level of radiation when in space, so it is essential to evaluate the risks and performance effects associated with extended radiation exposures in missions and space travel in general. This investigation focuses on LEO, especially in the near-equatorial radiation environment. Radiation experiments supported with simulations have made it possible to obtain and evaluate the electron radiation impact on optoelectronics at the device level and system level performances. The electron radiation has induced a system degradation of 70%. This result demonstrates the importance of such an investigation to predict and take necessary and suitable reliable quality service for future space missions.

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