SpreadFast Project

During the SPREADFAST project a list of solar energetic protons is compiled in order to serve as a pool of events for subsequent forecasting using the developed model.

The time period covers SDO data availability. The event list is based on SOHO/ERNE instrument with identified solar origin (solar flares and/or CMEs). All SEP-producing CMEs in the above period (~200) were inspected whether they propagate in a quiet IP environment, namely over the period of interest Δt (prior the SEP-related CME) no CMEs with the following properties had to be reported:
– no wide CMEs (e.g. with angular width larger than 60 degrees);
– no CMEs within a cone of +/- 45 degrees centered at the measurement position angle of the SEP-related CME.

The resulted list contains 59 proton events in total, see the table below. Among them:
– 37 events (plotted in blue) have Δt of 1 day, i.e. no CMEs over a period of 1 day prior the SEP-producing CME
– 22 events (plotted in green) have Δt of 3 days, i.e. no CMEs over a period of 3 days prior the SEP-producing CME.

The two stacked histograms show the distribution with respect to the proton intensity and over time (in solar cycle 24). The event list contains both small and large SEP events and is well distributed over periods of weak and strong solar activity.

SEPs_new_list