Session 7 - Radiation Environments: From Solar Origin to Effects on Space Missions
Eamonn Daly (ESA), Rositsa Miteva (Space Climate Group - Space Research and Technology Institute - Bulgarian Academy of Sciences), Larisa Kashapova (ISTP SB RAS, Russia), Richard Horne (British Antarctic Survey)
Wednesday 7/11, 09:00-10:30 & 11:15-12:45
MTC 00.15, Small lecture room
With the rapid growth in the exploitation of space for applications serving society, and ambitious plans for scientific missions, proper evaluation of the effects of the space environment on future space infrastructures is crucial for all aspects of this evolution. Evaluations of space weather and space environmental climate for these missions face numerous difficult challenges. Effects that have to be coped with include solar array degradation, dose effects on electronics and humans, electrostatic charging and discharging, and single event effects.
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Solar Energetic Particle (SEP) events are an important transient component of the space weather. It remains very difficult to predict the occurrence, magnitude and timing of SEP events at Earth based on observations of different types of solar precursors and eruptive events (solar flares, coronal mass ejections, etc.), and current understanding of physical solar processes, particle acceleration and transport. Similarly, the ability to predict time variations of the Earth’s Radiation Belts (RBs) is lacking. The belts respond to solar events via geomagnetic storms, but also reflect changes to the source and loss processes at low altitude via the atmosphere.
This session will focus on SEP and RB phenomena as sources of space environment hazards. For both SEP and RB environments, contributions discussing the following are solicited: end user experiences of effects and consequent needs; data processing and statistical analysis/modelling; and physics based modelling serving end user needs. These contributions can address both space weather and climatological (long-term statistical) aspects. The organisers encourage discussion of the needs of mega-constellations, missions with “electric orbit raising” and future human exploration such as the “deep space gateway”.
Talks : Time scheduleWednesday November 7, 09:00 - 10:30, MTC 00.15, Small lecture room
Wednesday November 7, 11:15 - 12:45, MTC 00.15, Small lecture room
|09:00||Recent results from the space radiation environment measurements aboard ExoMars Trace Gas Orbiter and comparison with the dose rate and flux estimations based on galactic cosmic ray models||Benghin, V et al.||Invited Oral|
| ||Victor Benghin, Jordanka Semkova, Rositza Koleva, Krasimir Krastev, Tsvetan Dachev, Yuri Matviichuk, Borislav Tomov, Stephan Maltchev, Plamen Dimitrov, Igor Mitrofanov, Alexey Malakhov, Dmitry Golovin, Maxim Mokrousov, Anton Sanin, Maxim Litvak, Alexander Kozyrev, Vladislav Tretyakov, Sergey Nikiforov, Andrey Vostrukhin, Natalia Grebennikova, Lev Zelenyi, Vyacheslav Shurshakov, Sergey Drobyshev|
| ||Space Research and Technology Institute, Bulgarian Academy of Sciences, Sofia, Bulgaria;Space Research Institute, Russian Academy of Sciences, Moscow, Russia; Institute of Biomedical Problems of the Russian Academy of Sciences, Moscow, Russia|
| ||ExoMars is a joint ESA - Rosscosmos program for investigating Mars. Two missions are foreseen within this program: one consisting of the Trace Gas Orbiter (TGO), that carries scientific instruments for the detection of trace gases in the Martian atmosphere and for the location of their source regions, launched on March 14, 2016; and the other, featuring a rover and a surface platform, with a launch date of 2020. On October 19, 2016 TGO was inserted into high elliptic Mars’ orbit and on April 16, 2018 has begun the science phase of TGO at circular Mars’s orbit at about 400 km distance from Mars.
The dosimetric telescope Liulin-MO for measuring the radiation environment onboard the ExoMars TGO is a module of the Fine Resolution Epithermal Neutron Detector (FREND).
We present recent results from measurements of the charged particle fluxes, dose rates, linear energy transfer spectra and estimation of dose equivalent rates in the interplanetary space, in high elliptic Mars’s orbit and first data in TGO science orbit, provided by Liulin-MO dosimeter aboard TGO.
The obtained data show that during the cruise to Mars dose rate varied in the range 0.37 – 0.42 mGy d-1 for absorbed dose rate and 2.0 – 2.3 mSv d-1 for equivalent dose rate.
The comparison of flux and dose rate measurements curried out by Liulin-MO dosimeter during the cruise of TGO to Mars with calculation based on galactic cosmic ray models show surplus of measured flux and dose rate on calculated.
The dosimetric measurements in high elliptic Mars’ orbit were used to estimate the flux shadow by Mars effect. Results of 23 TGO pericenter crossing were investigated. The “shadow effect” amounted to 30%, but as a rule was less than calculated one.
The very first results provided by Liulin-MO during the beginning of TGO science phase (16.04-13.05.2018) show that the dose equivalent rate at circular Mars’s orbit at about 400 km distance from Mars, obtained close to the solar activity minimum is about 1.5 - 1.6 mSv d-1 . This is approximately 80% of the dose rate during the cruise to Mars.
The results are important for future manned mission to Mars radiation risk estimations.
A similar module, called Liulin-ML for investigation of the radiation environment on Mars’ surface as a part of the active detector of neutrons and gamma rays ADRON-EM on the Surface Platform is under preparation for ExoMars 2020 mission.|
|09:15||SEP Acceleration by Coronal Shocks with Realistic Seed Spectra in the Low and Middle Corona||Kozarev, K et al.||Oral|
| ||Kamen Kozarev, Maher A. Dayeh, Pietro Zucca, Ashraf Farahat|
| ||Institute of Astronomy - Bulgarian Academy of Sciences - Bulgaria, Southwest Research Institute - USA, ASTRON - Netherlands, King Fahd University of Minerals and Petroleum - Saudi Arabia|
| ||Solar energetic particles (SEP) are accelerated in coronal mass ejections (CMEs) and flares, and propagate in the heliosphere, where they may pose a space radiation hazard to satellite electronics and astronauts. Over the last decade, it has been realized that CME-driven shocks may produce significant SEP fluxes during the early stages of eruptions, below 5 solar radii. Shocks are observed even lower in the corona, within 1.5 solar radii. Our aim is to study the capability of such large-scale coronal shocks to produce sizable fluxes of SEPs, in order to develop techniques for early forecasting of heliospheric space radiation. In recent work (Kozarev et al. 2018) we have modeled the acceleration of SEPs in the first 15-20 minutes of nine CMEs with dome-like shock waves, within the field of view of the SDO/AIA telescope (1.3-1.4 solar radii). Here, we extend this work, by modeling the shock SEP acceleration out to ~6 solar radii. We use realistic quiet-time, pre-event suprathermal particle spectra from 1 AU observations, and scale them back to the low corona to serve as seed spectra. For each event, SDO/AIA and SOHO/LASCO observations are combined with data-driven models, to characterize the compressive/shock wave kinematics and its interaction with the corona. The proton acceleration is then modeled using a time-dependent analytic diffusive shock acceleration model. We compare the resulting fluxes among events, based on the different coronal conditions that the shocks experienced.|
|09:30||Evaluating Solar Proton Constraints for Flight Operations||Minow, J et al.||Oral|
| ||Joseph I. Minow, Linda Neergaard Parker|
| ||NASA, Marshall Space Flight Center, Huntsville, Alabama USA, Universitites Space Research Association, Huntsville, Alabama USA|
| ||Space weather constraints are increasingly used by space system operators to avoid critical operations during extreme space weather events. One example is monitoring the flux of solar energetic particles (SEP) to protect a launch vehicle from exposure to extreme radiation environments. If the SEP ion flux exceeds an established threshold for a preselected energy, then launch operations may be deferred to a later time when the flux has dropped to safe levels. We will first introduce the concept of SEP launch constraints and provide examples of launch operations that have been delayed due to solar proton events to demonstrate the potential impact of using space weather launch constraints on launch operations. Next we describe an analysis tool we have developed to evaluate the efficacy of solar proton launch constraints. Historical records from the Space Environment Monitor (SEM) instrument suite on the GOES spacecraft are used as input to the tool to test the impact of launch decisions on launch operations including launch availability, potential exposure to SPE environments exceeding the constraint flux following launch, and false-alarms where launches were held but SPE flux would have been safe during flight. The historical SEM data are the same records available from NOAA Space Weather Prediction Center in real-time on day-of-launch to monitor the space radiation environment. Examples of SEP impacts on flight operations are then evaluated for a range of SEP energy and flux threshold parameters, pre-launch monitoring duration strategies, and post-launch critical flight operation periods to demonstrate the impacts of using space weather launch constraints on flight operations.|
|09:45||Towards a single framework for the modelling of Space Radiation Environment||Papadimitriou, C et al.||Oral|
| ||Constantinos Papadimitriou, Ingmar Sandberg, Sigiava Aminalragia-Giamini, Antonis Tsigkanos, Omiros Giannakis, Christos Katsavrias, Piers Jiggens, Ioannis A. Daglis|
| ||SPARC - Space Applications & Research Consultancy, Athens, Greece, IASSARS - National Observatory of Athens, Athens, Greece, National & Kapodistrian University of Athens, Athens. Greece, ESA ESTEC, Noordwijk, Netherlands|
| ||A new Space Radiation Environment Modelling system has been recently designed and implemented under ESA HERMES project. The architecture of the system is modular allowing the execution of multiple heterogeneous models and tools. The system modules are loosely coupled so that new modules can be easily added. The system integrates a series of space radiation environment models and applies a statistically robust and efficient methodology to combine the outputs of the modelled radiation effects attributed to various sources of particle radiation (Trapped Particles, Solar Protons and Galactic Cosmic Rays).
The current version of the system integrates the AE9/AP9/SPM model , the Trapped Energetic Particle Environment Model (TREPEM) , the Virtual Enhancements – Solar Proton Event Radiation (VESPER)  model and the Matthiä DLR model  for the Galactic Cosmic Rays. In addition, the Magnetospheric Shielding Model (MSM)  accounts for the shielding on solar proton and galactic cosmic flux series. The environment model outputs are coupled with state-of-the-art radiation effects tools (e.g. MULASSIS , IRONSSIS  and MCICT ) to estimate internal charging, ionising and non-ionising dose and single event effects. The probability distributions of the radiation effects - resulted from different sources - are merged statistically assuming various degrees of inter-correlations and provide as an output the confidence levels for the effects along a given satellite orbit. As a result, the developed Space Radiation Environment Modeling System captures the net effect from all radiation sources providing a single framework for the design and evaluation of future missions.
 G. P. Ginet, et al., "AE9, AP9 and SPM: New models for specifying the trapped energetic particle and space plasma environment," Space Sci. Rev., 179, 579-615 (2013).
 The Trapped Energetic Particle Environment Model, (see Poster, Session 7, ESWW 15)
 S. Aminalragia-Giamini et al., The virtual enhancements - solar proton event radiation (VESPER) model, J. Space Weather Space Clim. 2018, 8, A06
 Daniel Matthiä et al., Thomas Berger, Alankrita I. Mrigakshi, Günther Reitz, A ready-to use galactic cosmic ray model, Advances in Space Research, Volume 51, Issue 3, 2013, Pages 329-338, ISSN 0273-1177, https://doi.org/10.1016/j.asr.2012.09.022.
 F. Lei (RadMod Research), ESHIEM Project (ESA Contract 4000107025/12/NL/GLC): Technical Note 2a "Magnetosphere Shielding Model (MSM)", v1.5, July 2017.
 F. Lei, P.R. Truscott, C.S. Dyer, B. Quaghebeur, D. Heynderickx, P. Nieminen, H. Evans, and E. Daly, "MULASSIS: A Geant4 Based Multi-Layered Shielding Simulation Tool", Proceedings of IEEE Nuclear and Space Radiation Effects (NSREC’02), Phoenix (USA), 20-24 July 2002.
 P.R. Truscott (Kallisto Consultancy), ESHIEM Project (ESA Contract 4000107025/12/NL/GLC): Technical Note 2b "Ion Rapid 1D Shielding Simulation Software (IRONSSIS)", v1.0, February 2015.
 F. Lei, D. Rodgers, P. Truscott, MCICT - Monte Carlo Internal Charging Tool, 14th Spacecraft Charging Technology Conference, ESA/ESTEC, Noordwijk, NL, 04-08 APRIL 2016 1
|10:00||Four years of space weathering effects observed on the Gaia spacecraft||Serpell, E et al.||Oral|
| ||Edmund Serpell|
| ||Telespazio VEGA at ESOC|
| ||Gaia is the ESA astrometry mission to precisely map over a billion stars in the Milky Way Galaxy that has been in orbit around the second sun-earth Lagrange point since early 2014. The orbit was chosen due to its very stable thermal environment which, in combination with the single operating mode of the spacecraft, means that it has been possible to measure long term changes due to space weathering with high precision monitoring of the spacecraft temperature evolution. For fine attitude control Gaia uses dry nitrogen cold gas thrusters to counteract the solar radiation pressure which is dependent on the surface properties of the spacecraft. Changes to the cold gas thrust levels have been measured due to changes in the properties of the multi-layer insulation covering the structure. The pixels of the instrument camera are susceptible to damage by the passage of high energy charged particles and this has been observed as an increase in the charge transfer inefficiency over the mission lifetime. In addition to the long term trends the effects due to shorter periods of increased solar activity such as solar panel aging and computer processor and memory bit errors have been observed on Gaia. Although it is not equipped with a dedicated radiation monitoring instrument the giga-pixel CCD focal plane is able to provide useful measurements of the local charged particle environment by implementation of an onboard algorithm designed to identify charged particle tracks. In this paper we report on the space weathering effects observed on Gaia over a four year period including the largest solar flare of cycle 24 from September 2017.|
|10:15||GOES-16 Solar Energetic Heavy Ion Observations from the SEP Events of July and September 2017: Comparison with ACE, SOHO and GOES 13-15||Rodriguez, J et al.||Oral|
| ||Juan V. Rodriguez[1,2], Athanasios Boudouridis[1,2], Brian Kress[1,2], James J. Connell, Clifford Lopate, Richard Mewaldt, Rami Vainio, Miikka Paassilta, Osku Raukunen, Daniel Heynderickx, Ingmar Sandberg, Piers Jiggens|
| || University of Colorado CIRES,  NOAA National Centers for Environmental Information,  University of New Hampshire,  California Institute of Technology,  University of Turku,  DH Consultancy,  Space Applications & Research Consultancy,  European Space Research and Technology Centre (ESTEC)|
| ||The Geostationary Operational Environmental Satellite (GOES)-R series of U.S. NOAA meteorological satellites includes a new instrument for measuring heavy ions of solar and galactic origin, the Energetic Heavy Ion Sensor (EHIS). While GOES satellites have observed protons and helium nuclei of solar origin since the 1970’s, EHIS enables NOAA to observe heavy ions from carbon to copper. These observations are of practical importance owing to the hazards that solar and galactic heavy ions pose to spacecraft and humans in space.
EHIS consists of a single solid-state telescope whose field-of-view is directed radially outward in the geographic equatorial plane. This telescope includes an Angle Detecting Inclined Sensor system (ADIS, Connell et al., Nucl. Instr. and Meth. 457 (2001) 220) to resolve heavy ions by atomic number (Z). Each species is reported in five energy bands over an energy range that varies with Z (e.g., helium: 10-194 MeV/n, iron: 37-825 MeV/n). EHIS represents the first flight of an ADIS system in space.
The first satellite in this series, GOES-16, was launched on November 19, 2016, and EHIS made its first measurements on January 8, 2017. This talk focuses on EHIS observations of the solar energetic particle (SEP) events whose onsets were on July 14, September 4, September 6, and September 10, 2017 (the latter associated with ground-level enhancement (GLE) 72). As far as the magnitudes of these events and the different measurement ranges (in energy and Z) of the instruments permit, we compare the EHIS observations with observations by the Solar Isotope Spectrometer (SIS) on ACE, the Energetic and Relativistic Nuclei and Electron (ERNE) instrument on SOHO, and the Energetic Proton, Electron and Alpha Detectors (EPEAD) on GOES 13-15. The EPEAD data are interpreted using the effective energies derived for the SEPEM Reference Data Set v2.1 via cross-calibration with the IMP-8 Goddard Medium Energy (GME) experiment.
|11:15||The AE9/AP9-IRENE Radiation and Plasma environment models||O'brien, P et al.||Oral|
| ||T.P. O’Brien, W.R. Johnston, S. L. Huston, T.B. Guild, Y.-J. Su, C. Roth, R. Quinn|
| ||The Aerospace Corporation, Air Force Research Lab, Confluence Analytics, Inc. Atmospheric and Environmental Research|
| ||The AE9/AP9-IRENE climatology models integrate the latest observations and science into a tool satellite designers can use to develop radiation specifications for missions traversing the Earth’s radiation belts. The model covers trapped radiation and plasma from keV to GeV energies. It provides mean and transient environments, with confidence levels to assess margin. The model is under active development, with major updates occurring every one to two years to further address community requirements. We will present an overview of the model as well as a look ahead at upcoming features and improvements as the US and European teams begin working together in earnest|
|11:30||Evaluation of Solar Cell Radiation Damage during Electric Orbit Raising||Lozinski, A et al.||Oral|
| ||Alexander R. Lozinski, Richard B. Horne, Sarah A. Glauert, Giulio Del Zanna, Hugh D. R. Evans, Daniel Heynderickx|
| ||British Antarctic Survey, DAMTP – University of Cambridge, ESA, DH Consultancy|
| ||Electric propulsion technology now enables satellite operators to achieve geostationary orbit without the use of chemical propellant via so-called electric orbit raising. Whilst this makes big savings off the cost of launch by reducing mass, it includes the compromise of a longer raising period, during which satellites pass through the hazardous radiation environment of the Van Allen belts.
Increased radiation exposure during electric orbit raising must be accounted for by mission planners through the use of radiation environment models such as NASA’s AP9/AE9. However, case studies such as the CRRES mission show that our predictive capability is limited by the drastic changes to the proton (inner) belt and slot region that can occur in a worst case scenario. Furthermore, the lack of consensus in industry as to which models provide suitable estimates raises the risk for shielding to be over or under-designed.
We show the accumulation of damage calculated by a range of models in terms of non-ionising dose for a variety of electric orbit raising scenarios that have been used to date, and discuss how varying key engineering parameters affects the result. We use the reduction in solar cell performance as a measure of degradation, with the highest contribution coming from MeV-order trapped protons.
In particular, we show that the trajectory, solar cell coverglass thickness and state of the proton belt can affect solar panel degradation accrued during electric orbit raising and before the beginning of service by up to ~10%. We conclude that more real-time information is required on the transient nature of the outer proton belt to help assess radiation damage.
|11:45||PreMevE: a New Predictive Model for Megaelectron-volt Electrons inside Earth’s Outer Radiation Belt||Chen, Y et al.||Oral|
| ||Yue Chen[1,2], XiangRong Fu, Geoffrey D. Reeves[1,2], and Michael Henderson|
| ||1Los Alamos National Laboratory, Los Alamos, New Mexico, USA; New Mexico Consortium, Los Alamos, New Mexico, USA|
| ||Relativistic electrons trapped in Earth’s outer radiation belt present a highly hazardous radiation environment for spaceborne electronics. These electrons, with kinetic energies up to multiple megaelectron-volt (MeV), manifest a highly dynamic and event-specific nature due to the delicate interplay of competing transport, acceleration and loss processes. Thus, developing the capability of forecasting outer belt MeV electrons has long been a critical and challenging task for space weather community. Recent studies have demonstrated the vital roles of electron resonance with waves (including such as chorus and electromagnetic ion cyclotron); however, it remains difficult for current diffusion radiation belt models to reproduce behaviors of MeV electrons during individual geomagnetic storms, mainly because of the large uncertainties existing in input parameters. This work designs a new model called PreMevE that is able to predict storm-time changes of MeV electrons within the outer belt. This model, taking advantage of the cross-energy, L-shell, and pitch-angle coherence caused by wave-electron resonant interactions, ingests observations from belt boundaries—mainly NOAA POES from low-Earth-orbits (LEOs)—to provide high-fidelity nowcast (multiple hour prediction) and forecast (> ~1 day) of MeV electron fluxes over L-shells between 2.8-7 through linear filters. As a first of its kind, PreMevE can not only accurately predict incoming enhancements of MeV electrons during storms with 1-day forewarning time, but also reliably specify the evolving electron spatial distributions afterwards. The high performance of PreMevE is assessed against long-term in situ data from one Van Allen Probe and a LANL geosynchronous satellite. This new model enhances our preparedness for severe MeV electron events during post-RBSP era, and further adds new science significance to existing and future LEO space infrastructure.|
|12:00||OHB's proposal of an in-orbit cross-calibration of space environment sensors||Ideström, J et al.||Oral|
| ||Johan Ideström|
| ||OHB System AG, Bremen, Germany|
| ||All satellite manufactures are currently going through a design change by replacing their chemical propulsion with electrical propulsion, and facing new challenges. All future satellites will use Electrical Propulsion Orbit Raising (EPOR), which will result in an electrical GTO of 142 to 387 days, instead of chemical GTO of 14 days. Those prolonged EPOR periods spend a considerable time in the radiation belts and will cause much more ionizing dose at the beginning of the mission, up to 50% additional total dose of what is expect during 15 years in GEO. There is not enough data of the EPOR-GTO-region in the space radiation models which causes even more high uncertainties in the planning of those missions. Additionally challenges are extreme space weather events like Carrington (1859), Quebec (1989) and Halloween (2003), and an old threat is resurfacing again, High-Altitude-Nuclear-Explosion (HANE), which can cause EMP and radiation belt pumping.
Due to those new challenges are more space environment sensors on satellites needed for housekeeping (e.g. actually measuring instead of guessing), anomaly investigation (analyze in-orbit behaviour), mission life extension (actually dose versus design dose), future designs (validation of the space radiation models).
Space radiation sensors are normally only calibrated on ground. Cross calibration is only applied after the mission when data sets of sensors on different satellites are compiled into one radiation model data set. Both methods have their disadvantages. Ground calibration can't reproduce space radiation (mix of particles and energy-spectrum) and provides only a partial calibration. Post-mission-calibration of data sets is difficult when sensors flew on different satellites at different locations under different conditions. Therefore the conclusion is that more in-orbit cross calibration and qualification is needed.
In-orbit cross calibration of two or more space environment sensors would have the following advantages, it would be on the same satellite, at the same location & time, under the same conditions, and therefore provide a full comparison. The in-flight cross calibration would enhance the scientific value of the data sets of all involved sensors. Cross calibration and qualification could happen at the same time, e.g. old and new sensors flying next to each other on the same satellite.
OHB System started an initiative to promote more cross-calibration in space, with the aim to identify possible candidates of sensors, to research integration costs of those sensors, and to look for possible flight opportunities. The results of this initiative will be presented in this talk.|
|12:15||Non-diffusive processes leading to enhanced radiation belt fluxes: Global MHD/test particle simulations of extreme space weather events||Ravindra, D et al.||Oral|
| ||Ravindra T. Desai, Jonathan P. Eastwood, Lars Mejnertsen, Joe W. B. Eggington, Jeremy P. Chittenden|
| ||Imperial College London|
| ||The leading shock associated with interplanetary coronal mass ejections drives the sudden storm commencement phase associated with geomagnetic storms. The consequent compression and relaxation of the magnetosphere has been observed to accelerate protons and electrons up to MeV energies over timescales of a few minutes, and produce hazardous radiation belt populations which persist for years at a time (e.g. Blake et al., 1992). To study this non-diffusive acceleration process, we employ the three-dimensional MHD simulation code, Gorgon, to capture the global solar wind-magnetosphere interaction, and couple this to a test-particle simulation code where test-particle distribution are spawned and traced through the time-dependent MHD fields. We present results on the evolution of these simulated populations during scenarios representative of extreme Space Weather events, and examine the various source populations for the most intense radiation belt fluxes seen in the space age (Meredith et al., 2015). This simulation technique is evaluated with respect to the framework of physics-based models necessary for space weather forecasting. |
|12:30||Measurements and Effects of Energetic Charged Particles Aboard a CubeSat in Low Earth Orbit: Aalto-1 / RADMON||Vainio, R et al.||Oral|
| ||Rami Vainio, Arttu Punkkinen, Jan Gieseler, Heli Hietala, Philipp Oleynik, Juhani Peltonen, Thiago Brito, Hannu-Pekka Hedman, Edward Hæggström, Hannu Leppinen, Petri Niemelä, Samuli Nyman, Jaan Praks, Risto Punkkinen, Tero Säntti, and Eino Valtonen|
| || University of Turku, Finland,  University of Helsinki, Finland,  SSF, Finland,  Aalto University, Finland|
| ||Aalto-1  is a three-unit CubeSat launched to a Sun-synchronous Low Earth Orbit on 23 June 2017. It carries a radiation monitor (RADMON)  measuring charged particle radiation in orbit. RADMON is sensitive to >10 MeV protons and >2 MeV electrons.
We present an overview of the RADMON instrument and its first year of observations in space. As Aalto-1 is still in a tumbling mode, RADMON is scanning directions in the sky allowing one to generate an omnidirectional flux measurement from the counting rates of the detector. In addition to stably trapped electrons and protons in the Earth’s radiation belts, RADMON observes quasi-trapped electron populations, which have been scattered to the drift loss cone and are en route to be precipitated in the atmosphere. Occasionally RADMON also observes electrons in the bounce loss cone. In the first half of September 2017, RADMON made observations during the solar proton events, which were among the strongest ones in the present solar activity cycle and led to several space weather effects in orbit, including spontaneous reboots of the on-board computer of Aalto-1.
Acknowledgements. Aalto-1 and RADMON are an effort of a large number of students in Aalto University, University of Turku, and University of Helsinki. The work of Aalto-1 and RADMON student teams is gratefully acknowledged.
 A. Kestilä, T. Tikka, P. Peitso, J. Rantanen, A. Näsilä, K. Nordling, H. Saari, R. Vainio, P. Janhunen, J. Praks, and M. Hallikainen, Geoscientific Instrumenta-tion, Methods and Data Systems, 2 (2013) 121.
 J. Peltonen, H-P. Hedman, A. Ilmanen, M. Lindroos, M. Määttänen, J. Pesonen, R. Punkkinen, A. Punkkinen, R. Vainio, E. Valtonen, T. Säntti, J. Pentikäinen, and E. Hæggström, Proc. 10th European Workshop on Microelectronics Education (EWME), Tallinn, Estonia, 2014, p. 161. doi:10.1109/EWME.2014.6877418.|
|1||Detection in real-time and post-analysis of the GLE72 event||Tezari, A et al.||p-Poster|
| ||H. Mavromichalaki, M. Gerontidou, P. Paschalis, A. Tezari, C. Sgouropoulos, N. Crosby, M. Dierckxsens, V. Kurt, A. Belov, K. Kudela|
| || Athens Cosmic Ray Group, Faculty of Physics, National and Kapodistrian University of Athens, Athens, Greece  Royal Belgian Institute for Space Aeronomy (BIRA-IASB), Belgium  Institute of Nuclear Physics, Moscow State University, Moscow, Russia  Pushkov Institute of Terrestrial Magnetism, Ionosphere and Radio Wave Propagation RAS, Moscow, Russia  Institute of Experimental Physics, Slovak Academy of Sciences, Košice, Slovakia|
| ||The Ground Level Enhancement 72 (GLE72) was recorded on 10 September 2017 by several neutron monitors of the High-Resolution Neutron Monitor Database (NMDB, www.nmdb.eu). It is the second and probably the last GLE of Solar Cycle 24, one of the quietest Solar Cycles. GOES satellites registered a solar proton event coming from the solar active region AR2673 with energies above 10, 50 and 100 MeV, while particles of higher energies were recorded by the ground-based neutron monitor network. GLE72 was successfully detected in real-time by the GLE Alert Plus System of Athens Neutron Monitor Station (A.Ne.Mo.S., http://cosray.phys.uoa.gr), which is available to the European Space Agency under the Space Situational Awareness Program (ESA - SSA) in the Space Radiation Expert Centre (http://swe.ssa.esa.int/web/guest/space-radiation). The understanding of the origin and the mechanisms of severe Space Weather events, such as GLEs, as well as their accurate prediction in real-time are of great importance for the minimization of their consequences on technological and biological systems.
|2||Estimation of the particle radiation environment at L1 point and near-Earth space||Laurenza, M et al.||p-Poster|
| ||M. Laurenza, T. Alberti, M. F. Marcucci, G. Consolini, C. Jacquey, S. Molendi, C. Macculi, S. Lotti|
| || INAF – Istituto di Astrofisica e Planetologia Spaziali, via del Fosso del Cavaliere 100, 00133 Roma, Italy,  Institut de Recherche en Astrophysique et Planétologie Centre de Données de Physique des Plasmas CNRS, UPS, CNES, Université de Toulouse 9, avenue du Colonel Roche BP 44346 - 31028 Toulouse Cedex 4,  INAF – Istituto di Astrofisica Spaziale e Fisica Cosmica di Milano, Via Bassini 15, 20133 Milano|
| ||To properly characterize the particle radiation environment at L1 point and in the near-Earth space we performed a detailed analysis of the proton flux data obtained from different spacecraft and covering different observing periods. We focused on proton data in the poorly explored energy range 0.05—5 MeV, including energies of the so-called “soft protons”, which are critical for the ATHENA mission. Specifically, we used the ACE/EPAM measurements, covering the period between 1997 – 2015 (solar cycles No. 23 and part of No 24), the IMP-8 observations from 1973 to 2001 (solar cycles No. 21, 22, and part of No 23), and the Geotail ones from 1995 to 2001 (part of solar cycle No. 23). We estimated the energetic proton environment by computing the cumulative distribution functions (CDFs) for all the differential energy channels of each instrument. Then, we compared those obtained over equivalent energy channels of the different instruments. An overall good agreement was found over a common acquisition period, from 1997 to 2001. On the other hand, proton fluxes were observed to be higher of about a factor 3 during solar cycle No 21 and 22 with respect to those in solar cycle No 23. Finally, we obtained and fit the energetic proton spectra observed for 50% and 90% of the time coverage, as well as the worst case scenario, which can be used for operational purposes of the ATHENA mission and more generally for Space Weather related hazards.|
|3||Global atmosphere phenomenon||Balabin, Y et al.||p-Poster|
| ||Yury Balabin, Aleksey Germanenko, Boris Gvozdevsky, Eugenia Mikhalko|
| ||Polar Geophysical Institute, Apatity, Russia|
| ||At the present moment Cosmic Ray Laboratory of Polar Geophysical Institute has a row of gamma-ray detectors. There are six points of gamma-ray monitoring: Barentsburg (arch. Spitsbergen, 78º N), Tixie (arctic shore of Laptev sea, 71º N), Apatity (68º N), Yakutsk (62º N), Houlougay peak (Sayan mountains, 3000 m, 52º N), Rostov-on-Don (47º N). The employed detectors are the same and tested by the known characteristic lines of some elements. Also the detectors are in lead shield opened from top. A new phenomenon was carried out on each station. This is an increase event of gamma-rays coming from the atmosphere. The events are accompanied by precipitations, they occurred in any season. The increase amplitude is up to 60 %. Extended experiments on Apatity and Barentsburg stations proved an absence of radionuclide contamination in the precipitations. Also at these stations the gamma-ray detectors are incorporated with charged particle detectors. There is no increasing on charged particle detectors during precipitations. Especially increase events on Barentsburg and Houlougay peak are important. These stations are in uninhabited areas and far from industrial zones. In this work common features of the events and common conclusions concerning the events are present.|
|4||Characterization of the L2 radiation environment using ESA SREM measurements||Aminalragia-giamini, S et al.||p-Poster|
| ||S. Aminalragia-Giamini[1,2], S. Raptis, I. Sandberg, A. Anastasiadis, C. Papadimitriou, I. A. Daglis, P. Nieminen|
| ||Space Applications & Research Consultancy (SPARC), Greece; National Observatory of Athens, Greece; National & Kapodistrian University of Athens, Greece;ESA/ESTEC, The Netherlands|
| ||The radiation environment of the second Sun-Earth Lagrange point (L2) is of high interest for missions that aim to place spacecrafts there such as the upcoming X-ray Athena telescope, the James Webb Space Telescope and others. Solar Proton Events are a main source of radiation which can have serious and adverse effects on spacecrafts and their onboard equipment. However, little work has been done on the investigation of how such Events affect the radiation environment in L2. In this work we analyze data from the ESA Standard Radiation Environment monitor (SREM) on board the two L2 missions Herschel and Planck, as well as from the HEO INTEGRAL mission. A comparison of the SREM count-rates and the derived solar proton fluxes is performed, as well as an investigation of the error in the translation of INTEGRAL measurements to Herschel and Planck L2 environment. The flux analysis is based on the calculation of proton fluxes using both Singular Value Decomposition (SVD) and Artificial Neural Networks (ANN). Finally we present an estimation of the experimental cumulative distribution functions of solar proton fluxes for the Herschel and Planck missions.
This work received funding through the “AREMBES: ATHENA Radiation Environment Models and X-Ray Background Effects Simulators”, ESA Contract No. 4000116655/16/NL/BW
|5||SEP models coming to the Community Coordinated Modeling Center||Mays, M et al.||p-Poster|
| ||M. L. Mays, J. G. Luhmann, D. Odstrcil, N. A. Schwadron, M. J. Gorby, M. Dierckxsens, M. Marsh, I. Richardson[7,1]|
| || NASA Goddard Space Flight Center,  Space Sciences Laboratory, University of California, Berkeley  George Mason University,  University of New Hampshire,  Royal Belgian Institute for Space Aeronomy  UK Met Office,  University of Maryland College Park|
| ||Many solar energetic particle (SEP) models will soon be available via the Community Coordinated Modeling Center's (CCMC) Runs-on-Request system and the SEP Scoreboard. Several models have already been delivered and are currently being tested and incorporated into CCMC infrastructure. These include the Solar Energetic Particle Model (SEPMOD) (Luhmann et al. 2007, 2010, 2017), the Energetic Particle Radiation Environment Module (EPREM) (Schwadron et al., 2010), and the improved Particle Acceleration and Transport in the Inner Heliosphere (iPATH) model (Li et al, 2012; Hu et al. 2017). The Space Weather Modeling Framework's (SWMF) Field Line Advection Model for Particle Acceleration FLAMPA model will soon be delivered (Sokolov et al., 2004). In addition to complex models, CCMC will also host or gather real-time output from many empirical models for the SEP Scoreboard project. In this presentation we will briefly introduce these models and demonstrate the various options/modes available for users to setup their simulation requests at CCMC, and how users will be able to view real-time model output on the SEP Scoreboard. |
|6||Exploring the energetic proton flux variability by using the Empirical Mode Decomposition||Alberti, T et al.||p-Poster|
| ||T. Alberti, M. Laurenza, G. Consolini, M. F. Marcucci|
| ||INAF – Istituto di Astrofisica e Planetologia Spaziali, via del Fosso del Cavaliere 100, 00133 Roma, Italy|
| ||The interplanetary space is permeated by ’thermal’ solar wind plasma and by a higher energy particle component, which increases of several orders of magnitude during Solar Energetic Particle (SEP) events. The estimation of this high energy particle background variability is essential for both scientific and technological purposes, particularly for space mission profiles.
Here, the proton flux data in the energy range 0.047-4.75 MeV obtained from ACE spacecraft, covering the 1997 – 2017 interval (solar cycles No. 23 and 24) have been investigated by using the Hilbert-Huang Transform (HHT) approach, based on both Empirical Mode Decomposition (EMD) and Hilbert Spectral Analysis (HSA), to characterize their timescale variations and their relations with solar activity.
The analysis has shown that proton flux timescale variability spans from few days up to years. Specifically, variations at timescales <1 year have been found to be important even during the solar minimum phase and have been associated with the interplanetary recurrent structures (e.g., high speed streams and corotating interaction regions). On the other hand, longer-term (>1 year) variations in the energetic proton flux, e.g., to the quasi-biennal oscillations (QBOs), have been detected mainly in the maximum phase and linked to the variability of solar activity phenomena (e.g., those associated with SEP occurrence).|
|7||An Empirical Modification of the Force Field Approach to Describe the Modulation of Galactic Cosmic Rays Close to Earth in a Broad Range of Rigidities ||Heber, B et al.||p-Poster|
| ||J. Gieseler, B. Heber, C. Herbst |
| || Institute of Experimental and Applied Physics, University of Kiel, Kiel, Germany|
| ||On their way through the heliosphere, galactic cosmic rays (GCRs) are modulated by various effects before they can be detected at Earth. This process can be described by the Parker equation, which calculates the phase space distribution of GCRs depending on the main modulation processes: convection, drifts, diffusion, and adiabatic energy changes. A first-order approximation of this equation is the force field approach, reducing it to a one-parameter dependency, the solar modulation potential ϕ. Utilizing this approach, it is possible to reconstruct ϕ from ground-based and spacecraft measurements. However, it has been shown previously that ϕ depends not only on the local interstellar spectrum (LIS) but also on the energy range of interest. We have investigated this energy dependence further, using published proton intensity spectra obtained by PAMELA and heavier nuclei measurements from IMP-8 and ACE/CRIS. Our results show severe limitations at lower energies including a strong dependence on the solar magnetic epoch. Based on these findings, we will outline a new tool to describe GCR proton spectra in the energy range from a few hundred MeV to tens of GeV over the last solar cycles. In order to show the importance of our modification, we calculate the global production rates of the cosmogenic radionuclide 10Be which is a proxy for the solar activity ranging back thousands of years. |
|8||Solar and interplanetary sources of Solar Energetic Particle (SEP) Events during 1988-2013. Implications for SEP forecasting||Papaioannou, A et al.||p-Poster|
| ||A. Papaioannou, E. Paouris, A. Anastasiadis, A. Aran, R. Vainio, M. Paassilta, P. Jiggens|
| || Institute for Astronomy, Astrophysics, Space Applications and Remote Sensing (IAASARS), National Observatory of Athens, Greece,  Department of Quantum Physics and Astrophysics, Institut de Ciències del Cosmos, Universitat de Barcelona, Spain,  Department of Physics and Astronomy, University of Turku, Finland,  European Space Research and Technology Centre (ESTEC), Space Environment and Effects Section, Noordwijk, The Netherlands|
| ||The main sources of solar energetic particle (SEP) events are solar flares (SFs) and shock waves associated with coronal mass ejections (CMEs). SEP events are typically divided into two basic classes, the so-called “gradual” and the “impulsive” ones. Impulsive SEP events are associated with short timescales and are attributed to solar flares (SFs) and/or coronal shocks. Gradual events show timescales of days and are associated with coronal and interplanetary shocks; the main source of particles are assumed to be the CMEs, not disregarding the possible direct or indirect contribution by concomitant SFs.. We examined the properties and associations of 172 SEP events that occurred in the years 1988 to 2013. The associated solar events were parameterized by solar flare (SF) and coronal mass ejection (CME) characteristics. In particular, for SFs: the maximum flare flux, the flare fluence, the heliographic location, the rise time and the duration were exploited; for CMEs the plane-of-sky velocity as well as the size (as expressed by the width) were utilized. Furthermore, we also include data on the interplanetary counterparts of CMEs (ICMEs) as well as the presence (or not) of interplanetary shocks. We present comparative distributions of SF, CME and ICME characteristics in order to pinpoint the conditions that lead to SEP events. Moreover, we compare the productivity of SEP events within different solar cycles, aiming to shed light on the mechanisms that influence the rate of SEP occurrence and the number of SEP associated CMEs and SFs. Finally, significantly correlations that arise from our statistics are discussed.
This work was supported through the ESA Contract No 4000120480/17/NL/LF/hh "Solar Energetic Particle (SEP) Advanced Warning System (SAWS)"
|9||The solar particle event on 10-13 September 2017 – Spectral reconstruction and calculation of the radiation exposure in aviation and space||Matthiä, D et al.||p-Poster|
| ||Daniel Matthiä, Matthias M. Meier and Thomas Berger|
| ||German Aerospace Center (DLR), Institute of Aerospace Medicine, Cologne, Germany|
| ||The solar energetic particle event on 10 September 2017 and on the following days was the strongest event in recent years. It was recorded as Ground Level Enhancement 72 by Neutron Monitors Stations on the Earth and measured by a number of instruments in space. One aspect of such a space weather event is the potentially increased radiation exposure in aviation and space. Numerical simulations can help estimate the elevated dose rates during the event; a critical aspect in these simulations is the description of the primary particle spectrum. In this work, we present 1 hour averaged proton spectra during the event derived from GOES measurements and described by two different analytic functions. The derived proton spectra are used to calculate the radiation exposure in aviation and different space scenarios: low-Earth orbit, interplanetary space, and Mars surface and the results are discussed in the context of available experimental data. While the results indicate that in most of these scenarios in aviation and space the event was of little relevance compared to the total exposure from galactic cosmic radiation, the skin dose in a lightly shielded environment in interplanetary space may have reached about 30% to 60% of the NASA 30-day dose limit.|
|10||Radiation belts shape fluctuation due to geomagnetic disturbances||Protopopov, G et al.||p-Poster|
| ||Vasily S. Anashin, Grigory A. Protopopov, Nataliya V. Balykina, Andrey Y. Repin, Valentina I. Denisova, Alexey V. Tsurgaev|
| ||Branch of JSC URSC – ISDE, FSBI “Fedorov Institute of Applied Geophysics”|
| ||It is well-known fact that the Earth’s magnetosphere and the shape of radiation belt is strongly depends on solar activity characteristics such as solar wind speed. We tried to estimate quantitatively the connection between these characteristic with using of on-board measurements of particle fluxes at Meteor-M satellite for several years..
We determined space weather characteristics such as Dst index, solar wind speed and so on using open data sources, and shift of radiation belt during geomagnetic storms. The latter we determines as a shift of electron flux maximum, which are calculated using LB-map of electron flux during and before storms. Calculation results and results of correlation analysis will be presented in the full paper.|
|11||Monitoring and Interpretation of EPT proton and electron fluxes during 5 years of data||Botek, E et al.||p-Poster|
| ||Edith Botek, Graciela Lopez Rosson, Fabiana Da Pieve and Viviane Pierrard|
| ||Royal Belgian Institute for Space Aeronomy|
| ||The monitoring of energetic particles trapped at the Earth magnetic shielding as well as the understanding of their interactions into the belts are of capital importance for space design and operation engineering.
Temporal and spatial variations of proton and electron fluxes measured by the Energetic Particle Telescope (EPT) on board the ESA PROBA-V satellite are analyzed near the poles and at the South Atlantic Anomaly. The EPT retrievals are also compared with GOES satellite and Disturbance Storm Time Index (DST) data to investigate the impact of big and medium solar storms occurred since the beginning of data reception from EPT in 2013 through the correlation between data available from different sources.
These comparisons allow understanding particle composition and dynamics of the radiation belts to better identify source and loss mechanisms and also aim at extending previous analysis of Lopez Rosson (1) and Pierrard (2) with storms occurred during 2017.
(1) Pierrard, Viviane, and G. Lopez Rosson. "The effects of the big storm events in the first half of 2015 on the radiation belts observed by EPT/PROBA-V." Annales Geophysicae (09927689) 34.1 (2016).
(2) Lopez Rosson, G., and V. Pierrard. "Analysis of proton and electron spectra observed by EPT/PROBA-V in the South Atlantic Anomaly." Advances in Space Research 60.4 (2017): 796-805.
|12||Global model of plasmaspheric hiss from multiple satellite observations||Meredith, N et al.||p-Poster|
| ||Nigel Meredith, Richard Horne, Tobias Kersten, Wen Li, Jacob Bortnik, Angelica Sicard, Keith Yearby|
| ||British Antarctic Survey, UK, Boston University, USA, UCLA, USA, ONERA, France, University of Sheffield, UK|
| ||We present a global model of plasmaspheric hiss, using data from eight satellites, extending the coverage and improving the statistics of existing models. We use geomagnetic activity dependent templates to separate plasmaspheric hiss from chorus. In the region 22-14 MLT the boundary between plasmaspheric hiss and chorus moves to lower L* values with increasing geomagnetic activity. The average wave intensity of plasmaspheric hiss is largest on the dayside and increases with increasing geomagnetic activity from midnight through dawn to dusk. Plasmaspheric hiss is most intense and spatially extended in the 200-500 Hz frequency band during active conditions, 400 < AE < 750 nT, with an average intensity of 1128 pT^2 in the region 05-17 MLT from 1.5 < L* < 3.5. In the pre-noon sector, waves in the 100-200 Hz frequency band peak near the magnetic equator and decrease in intensity with increasing magnetic latitude, inconsistent with a source from chorus outside the plasmapause, but more consistent with local amplification by substorm-injected electrons. At higher frequencies the average wave intensities in this sector exhibit two peaks, one near the magnetic equator and one at high latitudes, 45^o < |MLAT| < 60^o, with a minimum at intermediate latitudes, 30^o < |MLAT| < 40^o, consistent with a source from chorus outside the plasmapause. In the pre-midnight sector, the intensity of plasmaspheric hiss in the frequency range 50-1000 Hz decreases with increasing geomagnetic activity. The source of this weak pre-midnight plasmaspheric hiss is likely to be chorus at larger L* in the post-noon sector that enters that plasmasphere in the post-noon sector and subsequently propagates eastward in MLT.|
|13||The Trapped Energetic Particle Environment Model||Papadimitriou, C et al.||p-Poster|
| ||Constantinos Papadimitriou,Ingmar Sandberg,Christos Katsavrias,Antonis Tsigkanos,Sigiava Aminalragia-Giamini,Piers Jiggens,Ioannis A. Daglis|
| ||SPARC - Space Applications & Research Consultancy, Athens, Greece, National & Kapodistrian University of Athens, Athens, Greece, Institute of Accelerating Systems and Applications, Athens, Greece, ESA ESTEC, Noordwijk, Netherlands |
| ||The ever-increasing number of launched satellites in the last decade, as well as possible future changes in their propulsion (from chemical thrusters to the much slower but more economic electric or electromagnetic propulsion systems) creates the need for a better understanding and modelling of the radiation environment that these satellites will encounter. The Trapped Energetic Particle Environment Model (TREPEM) is the latest incarnation in a long series of statistical, data driven models that attempt to describe the trapped energetic particle populations of the Earth’s radiation belts. Based on previous European efforts, that culminated in the production of the Slot Region Radiation Environment Models (SRREM), as well as on the widely used American AE9 & AP9 (IRENE) models, TREPEM aggregates data from a multitude of magnetospheric missions and converts them into “flux maps”, i.e. three-dimensional grids in a generalized “phase space” of Energy, equatorial pitch angle and L*, which hold the statistical distribution of omnidirectional fluxes for each grid point. By making use of carefully selected percentiles as a proxy for the probability distributions, we have devised a statistical description which is free from assumptions on the functional form of the flux distributions and thus can provide a purely data driven portrayal of the particle populations. Running a fly-in module on these flux maps allows the model to produce both time-series of the expected particle fluxes (average or any percentile) that a future mission will encounter, as well as a synoptic histogram with the probabilities of all possible fluxes that the satellite will have to fly through for the entirety of its planned mission.|
|14||In-depth validation of the IRENE models||Heynderickx, D et al.||p-Poster|
| ||D. Heynderickx, I. Sandberg, C. Papadimitriou, S. Aminalragia-Giamini, P. Truscott, F. Lei, I.A. Daglis, H. Evans, P. Jiggens|
| ||DH Consultancy, Leuven, Belgium, SPARC, Athens, Greece, Kallisto Consultancy, Farnborough, UK, RadMod Research, Camberley, UK, IASA & National and Kapodistrian University of Athens, Athens, Greece, ESA/ESTEC, Noordwijk, The Netherlands|
| ||VALIRENE is a two year project (ESA Contract No 4000117974/16/NL/LF) to perform a detailed evaluation of the IRENE models against in situ datasets and other radiation environment models.
In preparation of the actual validation, an extensive evaluation of available radiation belt datasets was performed, including re-calibration and cross-calibration of in situ datasets. The consolidated datasets are
one of the two sources to perform the model validation, by direct comparison of fluence spectra from the datasets to model runs over the spacecraft locations, and by statistical evaluation using scatter and whisker plots.
The second part of the evaluation consists of running the models on nominal spacecraft trajectories (including electric orbit raising orbits),comparing fluence spectra obtained with different models, and in addition comparing radiation effects calculated by running the particle spectra through well established radiation effects tools.
In order to facilitate and automate as much as possible the validation runs, a toolkit was developed to extract spacecraft locations and flux or count data from the various datasets (stored in an ODI database), to
perform model runs over the spacecraft locations and produce the required plots and statistical quantities. Folding of particle spectra with radiation effects tools and response functions is also handled by the
European space industry was briefed and consulted throughout the activity, providing valuable feedback. The project formulated recommendations for updates of the ECCS-E-ST-10-04 space environment standard.|
|15||Non-stationary properties of quasi-periodic pulsations in flare emission||Kupriyanova, E et al.||p-Poster|
| ||Elena Kupriyanova, Anne-Marie Broomhall, Dmitrii Kolotkov, Alexandra Lysenko, Kudryavtseva Anastasiya|
| ||Pulkovo Observatory RAS, Saint Petersburg, Russia, University of Warwick, Warwick,UK,  Ioffe PTI,Saint Petersburg, Russia,  ISTP SO RAS, Irkutsk,Russia|
| ||One of the principal questions in solar physics is related to the energy release and energy transport in solar flares. Quasi-periodic pulsations (QPPs) are the key property of the flares. They are observed in various frequency ranges of electromagnetic spectrum, from gamma rays to radio waves, during all phases of solar flares. Development of diagnostics of mechanisms of the QPPs allows understanding the processes both qualitatively and quantitatively. Up to date, methods of diagnostics are developed basing on the events with the QPPs having stationary parameters, and these pulsations are a particular case of the QPPs in general. However, non-stationarity of the parameters (deviation from a sine curve) of the QPPs is predicted from theoretical models of QPPs based on either on MHD oscillations of plasma structures or on auto-oscillations or on a combination of the previous two. Recently, the evidences were found on the presence of the QPPs with the time dependent parameters (hereinafter, non-stationary QPPs) in solar and stellar flares. Therefore, we are aiming to develop the method for detection and analysis of the statistically significant non-stationary QPPs. In this talk we present first results of testing the method on the simulated time profiles with following application of the method to solar flare events. |
|16||Middle atmospheric ionization during solar proton events in WACCM-D and riometer observations||Heino, E et al.||p-Poster|
| ||Erkka Heino[1,2], Pekka T. Verronen, Antti Kero, Niilo Kalakoski, Noora Partamies|
| ||Department of Arctic Geophysics, The University Centre in Svalbard, Department of Physics and Technology, University of Tromsø, Space and Earth Observation Centre, Finnish Meteorological Institute, Sodankylä Geophysical Observatory, University of Oulu|
| ||Energetic particle precipitation (EPP) --- solar proton events (SPEs), precipitating RB electrons, and auroral electrons --- causes increased ionization down to stratospheric altitudes, affecting the neutral composition and dynamics of the atmosphere in the geomagnetic polar regions. The EPP effect on ozone is of particular interest, as changes in ozone concentrations in the stratosphere have been shown to affect ground-level climate variability in the polar regions. The implementation of EPP ionization in climate models is necessary to understand the role of EPP in climate variability on longer time scales.
The extent and magnitude of atmospheric ionization caused by 63 SPEs during 2000 to 2005 were studied using the Whole Atmosphere Community Climate model with added D-region ion chemistry (WACCM-D), and observations of cosmic noise absorption (CNA) from 16 different riometer stations, covering a large geomagnetic latitude range in two longitude sectors.
The time behavior, zenith angle dependence, and magnitude of the modeled and observed CNA agree well in the polar cap, while the stations in the auroral zone are heavily affected by the gradual proton cutoff latitudes. As no cutoff latitude model is implemented in the WACCM-D model, the modeled CNA is overestimated at latitudes where the access of protons into the atmosphere is limited by their cutoff rigidity. The ability of the model to reconstruct CNA during SPEs, future improvements to the model inputs, and the applicability of the model will be discussed.|
|17||Forecast of relativistic electron fluxes in the Outer Radiation Belt at geosynchronous orbit with Machine Learning Methods||Myagkova, I et al.||p-Poster|
| ||Irina Myagkova, Aleksandr Efitorov, Yuliya Shugay, Sergey Dolenko|
| ||M.V.Lomonosov Moscow State University, D.V.Skobeltsyn Institute of Nuclear Physics, Moscow, Russia |
| ||The forecast of relativistic electron flux in the outer radiation belt (ORB) of the Earth is an important problem in the solar-terrestrial physics, since the flux of the relativistic electrons at geosynchronous orbit can enhance by several orders of magnitude during one day and less. Such changes can be observed as during geomagnetic disturbances, as when the solar wind velocity at the orbit of the Earth increases sharply not leading to geomagnetic storm.
Due to the increasing number of spacecraft in the near-Earth orbit and to the miniaturization of satellite electronics, the number of failures caused by the impact of relativistic electrons of outer radiation belt will raise further in future. Today there are sufficiently large space data arrays available that were accumulated over the years of observation. For this reason, it becomes possible to use machine learning methods trained on the available data array.
This paper presents a system for predicting the values of daily average fluxes of ORB relativistic electron at geosynchronous orbit based on the information about solar wind parameters and interplanetary magnetic fields measured by ACE spacecraft, Dst and Kp geomagnetic indexes from Kyoto World Data Center, and relativistic electron fluxes from GOES series spacecrafts. To increase prediction horizon and to improve the quality of prediction for larger horizon values, in this study we extend the set of input features for ORB relativistic electron flux forecast with the estimation of solar wind velocity several days ahead based on the coronal holes area measured by the images of the Sun obtained from Solar Dynamics observatory.
This study has been performed at the expense of Russian Science Foundation, grant no.16-17-00098.
|18||Increases and decreases in radiation belt electron content with geomagnetic activity||Forsyth, C et al.||p-Poster|
| ||Colin Forsyth, C.E.J. Watt, M. P. Freeman, C.-L. Huang, A. J. Boyd, M. Lockwood, K. R. Murphy, I. J. Rae, H. E. Spence, R. Caro Carretero[1,7]|
| ||UCL Mullard Space Science Lab., Dorking, United Kingdom, University of Reading, Reading, United Kingdom, British Antarctic Survey, Cambridge, United Kingdom, University of New Hampshire, Durham, NH, United States, New Mexico Consortium, Los Alamos, NM, United States, NASA Goddard Space Flight Center, Greenbelt, MD, United States, Comillas Pontifical University of Madrid. ICAI- School of Engineering. Spain|
| ||Earth’s outer radiation belt is populated by near-relativistic trapped electrons between ~3-8 RE in the magnetic equatorial plane; a region also populated by spacecraft in geostationary, medium and low Earth orbits. The number of electrons varies by several orders of magnitude on the timescale of hours to days. These variations, particularly increases in the radiation belt populations, are often associated with geomagnetic storms and substorms. Under this premise, we examine the extent to which changes in the radiation belt content are separated by geomagnetic activity. Intervals of SYM-H < -16 nT for more than 42 min in 3 h or, SML < -251 nT once within 3 h, show moderate skill in identifying increases in the total radiation belt electron content (TRBEC), with the best skill achieved when SML activity is persistent for 4 out of 7 three-hour intervals. Classifying proportional changes in TRBEC into those from quiet, transiently active and persistently geomagnetically active times using SML, we find that the distribution of changes is well described by three overlapping Gaussians. Quiet times are dominated by a narrow Gaussian (= -1.8% per 3 h) characterizing a lossy radiation belt and persistently active times by a wide Gaussian (=3.5% per 3 h) encompassing both enhancements and losses. These results are interpreted as showing that net changes in TRBEC are stochastic and that this nature can account for the apparent discrepancy between geomagnetic storms producing increases, decreases and no changes in the radiation belts.|
|19||Nuclear hardening to protect satellites against high-altitude-nuclear-explosions (HANE)||Ideström, J et al.||p-Poster|
| ||Johan Ideström|
| ||OHB System AG, Bremen, Germany|
| ||Satellites in space face many threats: natural threats like space weather (Carrington event), meteoroids, atomic oxygen, natural radiation from the sun and the radiation belts; and man-made threats like space debris, jamming, cyber hacking, artificial radiation and electromagnetic pulse (EMP) from High-Altitude-Nuclear-Explosions (HANE).
The most famous example of HANE, is the 1962 Starfish Prime nuclear explosion (1.4Mt TNT equivalent) in the pacific at 400 km altitude. This caused the biggest known EMP, much bigger than expected, even in Hawaii (1445km from the explosion) were artificial polar lights observed and 300 street lights malfunctioned. The HANE damaged as well 8 satellites, of which 7 failed completely just in months after the explosion. In 1962 were only a total of 32 satellites orbiting the earth and with 8 damaged satellites by Starfish Prime, it corresponds to a knock-out quota of 25%. Nowadays are over 1000 satellites orbiting earth in LEO, therefore could a similar event to Starfish Prime result in over 250 damaged satellites.
The protection of satellites against the effect of a HANE is called nuclear hardening. During the cold war was HANE a serious concern which resulted in the nuclear hardening of military satellites, the most famous example being the GPS satellites. After the cold war the threat scenario changed and with it the need for nuclear hardening declined. But due to most recent geo-political developments in North-Korea, a new threat-scenario is surfacing, and nuclear hardening is considered again.
Until today only few nations build military satellites with nuclear hardening in mind. Commercial customers are not considering it, and even new GNSS systems like Galileo are not taking it in account. All satellite manufactures are currently going through a design change by replacing their chemical propulsion with electrical propulsion. They are facing new challenges with Electrical-Propulsion-Orbit-Raising (EPOR) periods of up to 387 days, therefore spending more time in radiation belts and accumulating up to 50% more total-dose then previous missions. This added radiation dose of EPOR requires anyway an update of the satellites radiation shielding design, and then it makes sense include hardening against extreme space weather (Carrington) and HANE as well, since synergies in hardening against EPOR/Carrington/HANE are to be expected.
This presentation will give an overview of the history of HANE, list direct and indirect emissions and effects (e.g. radiation belt pumping), and finally present strategies to harden satellites against those effects.|
|20||Space radiation dosimetry and radiation shielding in LEO orbit on board CubeSat VZLUSAT-1||Daniel, V et al.||p-Poster|
| ||Vladimir Daniel, Tomas Baca, Carlos Granja[1,3], Lenka Mikulickova, Veronika Stehlikova, Adolf Inneman, Richard Pavlica, Vojtech Zadrazil, Petr Svoboda, Michaela Martinkova, Martin Urban, Ondrej Nentvich, Michal Platkevic, Robert Filgas|
| ||Czech Aerospace Research Centre, VZLU, Prague, Czech Republic Czech Technical University, Prague, Czech Republic ADVACAM, Prague, Czech Republic TTS, Prague, Czech Republic Rigaku, Prague, Czech Republic 5M, Kunovice, Czech Republic|
| ||The results of space radiation dosimetry in LEO polar orbit 500 km on board the nanosatellite VZLUSAT-1 are presented. The CubeSat VZLUSAT-1, part of the QB50 mission, was launched by PSLV rocket on 23rd June 2017. The main payload is a miniaturized X-ray telescope equipped with a focal-plane Timepix detector which serves also as high-resolution radiation monitor and quantum imaging dosimeter of the space radiation environment. For this purpose, Timepix performs regular but sparse measurements, due to limited data downlink rate, sampling the mixed radiation field on average several times per orbit. From the beginning of the mission over 9 month observations were performed showing temporal and spatial changes in the radiation belt distribution and intensity. Also geomagnetic storms following solar flares were detected. Results are presented also from a dedicated radiation shielding experiment as the second payload of VZLUSAT-1. A set of XRB diodes measure the total ionizing dose of the radiation field in open space, behind radiation shielding composite material and behind tungsten shield. The composites are based on standard carbon fibers and special resin for enhanced radiation hardness. The TID comparison enables to evaluate the shielding effectiveness. From the results we can state the novel composite radiation shield material, providing lower mass and higher stiffness, has comparable radiation shielding parameters with the standard aluminum materials. The shielding performance is greater at low energies with respect to the tungsten shield.|
|21||Microwave emission of solar flares as indicator of the SEP origins||Kashapova, L et al.||p-Poster|
| ||Larisa Kashapova,Rositsa Miteva,Natalia Meshalkina, Dmitrii Zhdanov, Irina Myagkova, Andrey Bogomolov|
| || Institute of Solar-Terrestrial Physics, SB RAS, Irkutsk, Russia  Space Research and Technology Institute – BAS, Sofia, Bulgaria  Skobeltsyn Institute of Nuclear Physics, Moscow State University, Moscow, Russia|
| ||The solar energetic particle events( SEPs) are one of the Space Weather factors. The SEP particles could be accelerated in the solar atmosphere during the solar flares or on shock waves, driven by coronal mass ejections (CMEs). One way to identify the mechanism is based on correlation analysis between the parameters of the solar origins (flares and CMEs) and the SEP particle parameters measured in situ.
The microwave (MW) emission is a sensitive indicator of particle acceleration in solar flares, and it was already used in previous studies. But the results are still ambiguous because of MW emission sensitivity to several physical parameters simultaneously. However, separate analysis of the event groups with more homogeneous physical/topological properties could improve the importance of the relationships. We present the results of the analysis based on the comparison of spectral properties of MW emission in solar flares associated with strong SEP events observed during the previous solar cycle. The main results are p resented and discussed.||