S. Bourdarie

Outer Electron Belt Specification Model

Data assimilation techniques have already been developed and have shown to provide ldquothe bestrdquo estimate of the state of the electron radiation belts. Data assimilation proceeds in analysis cycles-in each analysis cycle, observations of the current (and possibly past) state of a system are combined with the results from a mathematical model (the forecast) to produce an analysis, which is considered as the best estimate of the current state of the system. In this paper, such an analysis has been performed from January 1990 to December 2006 and has produced full electron radiation belt state every 20 min. Then, based on this 17 year run, a new outer electron belt specification model is developed: we perform a data synthesis to deduce a yearly average electron belt state over a full solar cycle. Lastly, this new specification model for the Earths radiation belt is compared to existing specification models.

Radiation Belt Activity Indices and Solar Proton Event Alarm

In the frame of the ONERA-CNES CRATERRE project, which aims to organize studies around radiation belt specification models, the local database Ionizing Particle ONERA Database (IPODE), gathering measurements from many radiation detectors, is presented. Relying on this daily updated database, two radiation belt activity indices with electron flux measurement (> 300 keV and > 1.6 MeV) and one solar proton event alarm with proton flux measurement (> 75 MeV) are developed for postevents analysis. Approach definition and validation are detailed for both indices and alarm. Those indicators are plotted over the last 30 days on the CRATERRE project website and are updated every day.

Correlation of in-flight displacement damage on the OSL sensor with space environment on-board Jason- 2 spacecraft

Displacement damage doses measured by the ICARE-NG/OSL sensor on board the French JASON2 spacecraft from CNES, the French space agency, are compared to predictions performed with (1) proton measurements performed with the spectrometers on board the same spacecraft/instrument and (2) protons spectrum predicted by the legacy AP8min model and the future AP9 perturbed model.

Anomalies of the ADSP 21060 Onboard the DEMETER Satellite

The micro-computer ADSP21060 (Analog Device) of the DEMETER satellite experienced a number of anomalies referenced as Single Event Effects (SEE). The events recorded outside the south Atlantic anomaly are not correlated to solar flare protons. The two main potential causes of these anomalies are the SEUs induced by the cosmic rays and the electrostatic discharge pulses able to trigger within the ADSP21060 some transients analogous to a single event effect. Both hypotheses are analysed. A correlation of the DEMETERs anomalies with the particles fluxes of the space environment has been performed using the IPSAT toolkit . A direct comparison of the DEMETERs anomalies is performed with the SEUs measured onboard the SAC-C satellite that flies on a similar orbit , . The correlation with internal charging/discharging phenomenon is also investigated by means of a simple electrical potential calculation.

Benchmarking ionizing space environment models

In flight feedback data are collected such as displacement damage doses, ionizing doses on board various space vehicles and are compared to predictions performed with (1) proton measurements performed with spectrometers data on board the same spacecraft if any and (2) protons spectrum predicted by the legacy AP8min model and the AP9 mean model.

Radiation Belt Activity Indices and Solar Proton Event Alarm on the CRATERRE project web site

Two Radiation Belt Activity Indices, based on electron flux measurement >300 keV and >1.6 MeV, and one Solar Proton Event Alarm, based on proton flux measurement >75 MeV, are developed for post events analysis. Both indices and alarm are plotted over the last 30 days on the CRATERRE project web site and are daily updated.