VALIRENE WP5000 Toolkit and Validation Commercial-in-Confidence – not for public release VALIRENE WP5000 Toolkit and Validation Pete Truscott & Daniel Heynderickx Kallisto Consultancy & DH Consultancy ESTEC, 12th November 2018 12/11/2018

Purpose-Built Toolkit for Validation Comprehensive toolkit to generate spacecraft trajectories, calculate trapped environment fluxes and fluences, and shielded effects Python-based (v3.6), strongly OO’d toolkit Interfaces with: PyIRENE (CythonIRENE C++ subroutines/classes, v1.50.001) and can also read in IRENE-generated O/P files Access to established models: AP8, AE8, CRRES-PRO, CRRES-ELE IGE, MEOv1 and MEOv2 models implemented in Python SRREM API from DHC – not yet fully linked-in NAIF SPICE orbit generator Can input and process some SPENVIS files types (e.g. SAO, SPE, SPP, etc) Comparison and manipulation of: flux- and fluence-based quantities TID, TNID, DDEF Python API for ODI database interface Operates in Linux, but intended for Windows as well 12/11/2018

Validation performed against instrument datasets Data processed - protons: Integral/IREM, 60s (2003 - 2006, 2008 - 2014, 2016 – 2018) RBSP-A/RPS, 60s, (2013-2016) RBSP-A/REPT, 120s (2012-2018) PROBA-1/SREM, 60s (2002-2018) Azur/EI-88, 60s (1969 & 1970) XMM/ERMD, 60s (2000 – 2017) Data processed – electrons: Integral/IREM, 60s (2003-2018) RBSP-A/REPT, 120s (2013-2018) PROBA-1/SREM, 30s (2002-2018) CRRES/MEA, 60s (1990-1991) XMM/ERMD, 60s (2000 – 2018) Data processed – counts IREM and SREM 12/11/2018

IRENE Model Outputs Additional quantities used: Description Mean Conventional mean of the environment at each point Percentile Captures statistical behaviour of the data upon which the model is built Perturbed Mean Includes uncertainties in mean flux maps due to measurement and gap-filling errors Monte Carlo Includes “perturbed” mode uncertainties, and adds estimate of dynamic variations due to space weather Additional quantities used: Perturbed Mean Percentile (PMP) – based on 40 different Perturbed Mean calculations for the same trajectory, and determination of the 95th or 75th percentile of the environment overall or for LL+L Monte Carlo Percentile (MCP) – based on 40 different Monte Carlo calculations for the same trajectory, and determination of the 95th or 75th percentile of the environment overall or for LL+L 12/11/2018

INTEGRAL/IREM Proton comparisons 12/11/2018

INTEGRAL/IREM Proton comparisons (12.4 – 41.1 MeV) 12/11/2018

INTEGRAL/IREM Proton comparisons (52.2 – 173.0 MeV) 12/11/2018

RBSP-A/REPT and RBSP-A/RPS Proton comparisons 12/11/2018

RBSP-A/RPS Proton comparisons (58.1 – 143.0 MeV) 12/11/2018

Proton Energy Spectra 12/11/2018

Summary for Level of Agreement for AP9 versus AP8 12/11/2018

INTEGRAL/IREM Electron comparisons 12/11/2018

INTEGRAL/IREM Electron comparisons (0.7 – 1.8 MeV) 12/11/2018

CRRES/MEA Electron comparisons (0.14 – 0.51 MeV) 12/11/2018

CRRES/MEA Electron comparisons (0.6 –1.09 MeV) 12/11/2018

Electron Energy Spectra 12/11/2018

Electron Mean Annual Flux * * * IRENE 95th MC percentile * * 12/11/2018

Summary for Level of Agreement for AE9 versus AE8 12/11/2018

Model results for standard orbits Four standard orbits considered: GEO 75E, but also some results for 180E and 285 MEO: 20,500km, 55 (GPS orbit) SSO: 800km, 98.6 ISS: 450km , 51.6 Electric propulsion orbit raising trajectories (courtesy of OHB): GTO to GEO, <0.25 142 days LEO to MEO, 56, 349 days LEO to GEO, 1, 387 days 12/11/2018

Electron Spectra for GEO and MEO IRENE Mean and PMP within a factor of 1.7 over 0.4 – 10 MeV AE8MAX predicts slightly higher fluxes than IRENE 95th PMP Difference between MEOv2 upper and mean fluxes greater than differences in the IRENE and AE8MAX results Very good agreement between AE9 and AE8 0.1 to 4 MeV >0.1 MeV, IRENE can be >10 higher than IGE The flux predicted by AE9 at 10MeV may be an artifact of the model 12/11/2018

Proton Spectra for SSO and ISS AP9 does not predict softer component <1MeV From 1 to 100 MeV, AP9 results 2.2 AP8MIN or 2.8 AP8MAX Again AP9 does not predict softer component <1MeV AP8MIN between 1-50 MeV matches the AP9 mean, but AP8MAX is up to 11 lower IRENE 95th PMP results 2- 3 the IRENE Mean predictions 12/11/2018

Conclusions (1) Protons: The IRENE provides Mean model is in better agreement with data than AP-8 for >40-50 MeV and for L above >1.6-2.0 (depending on energy) Within 15 – 40MeV, AP8 appears to be better, as well as for higher energies at L below 1.6-2.0 Note: improved model for low-altitude region being developed for ESA RENELLA Project activity. Electrons For L-regions >2.5 comparisons indicate that the IRENE Mean model for electrons provides comparable performance as AE-8 models There are regions (defined in terms of energy and L-range) where IRENE is better (particularly at energies >2 MeV) but: not systematically definable often there are significant differences between the model and data 12/11/2018

Conclusions (2) For low-altitude, high-inclination orbits, IRENE should be used with caution Neither the Perturbed Mean nor Monte Carlo modes (PMP and MCP results) seem to be able to capture the dynamic range seen in the electron data AE9 IRENE 95th PMP combined with 2x AE-8 MAX may provide a design margin based on the mean flux from the data Further assessment of this approach needed, considering variability/uncertainties in measured environment 12/11/2018

Conclusions (3) IGE-2006 predicts much lower GEO electron fluxes than IRENE and AE-8 predictions Note IRENE may overestimate the high energy electron fluxes IRENE Mean and 95th PMP environment and effects are typically between the equivalent values predicted by MEOv2 For EPOR trajectories: For short (<1 year) trajectories, IRENE Monte Carlo-model mode should also be used to aggregate the fluence and effects quantities Dominance of the trapped protons on the effects means space weather variability modelled by IRENE is of second-order importance for the GTO-to-GEO trajectory Validation will be further refined and extended during the remainder of the VALIRENE project 12/11/2018