D. Lazaro

In Flight Measurements of Radiation Environment on Board the French Satellite JASON-2

This paper presents particle flux measurements (protons and electrons) obtained with the ICARE-NG detector on the JASON-2 orbit (1336 km alt., 66° incl.) for the period June 2008-Aug. 2010. At this altitude, the South Atlantic Anomaly is greatly broadened as compared to lower altitudes. Proton flux measurements are made in the range 27.5-290 MeV and electron flux in the range 1.6-3.6 MeV. A great care was taken to assess the influence of the satellite on the particle measurements. Comparison of measurements with the results of the AP8 MIN model are given for protons, taken into account environment anisotropy.

A New Proton Model for Low Altitude High Energy Specification

A model of high energy protons for low altitude (below 800 km) mission specification was developed. This model is based on the long duration NOAA measurement series. We used only the highest omnidirectional channel from SEM on board the old NOAA satellites, and the corresponding channel from SEM-2 on board the new NOAA ones, as the other channels are contaminated by electrons. This gives us a basis for the model for E > 82 MeV protons. This model was extended in energy by using ICARE-NG measurements on board JASON-2 and HEPAD measurements on board NOAA-6. It gives integrated proton flux in the range 80-600 MeV at altitudes lower than 800 km along the solar cycle.

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.

Is Carrington event in 1859 really worse than other recent extreme events

The goal of this study is to try to answer the question: is Carrington event the worst event of all time? First, a state of the art on the 1859 Carrington event will be conducted, including recalling the sequence of events and the various data available. Then the second part will be devoted to the study of magnetic activity during the Carrington event in comparison with other more recent events. A KEquivalent index was calculated from magnetic data measured by the ground stations during the 1859 events and during other remarkable events in the space age. Moreover a correlation between this KEquivalent index and the tri-hour index Kp have been done. The result of this study seems to show that Carrington event was really an extreme event but some more recent events are roughly comparable.

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.