X9.3 flare of September 6 2017 and its associated solar radio burst

X9.3 flare of September 6 2017 and its associated solar radio burst

NOAA region 2673 produced a X9.3 flare on September 6 2017, peaking at 12:02 UT. It was accompanied by an intense and complex radio event displaying a low frequency type II burst, and a type IV burst spanning the entire frequency range covered by the ARCAS and HSRS spectrometers in Humain.

A lot of fine structures (spikes, zebra bursts. etc...) can be seen in the dynamic spectra shown here.

A preliminary analysis of light curves (see below) at certain frequencies shows an intensity of about 25 dB above the quiet sun level near the peak of the flare (12:02 UT), above 1 GHz. Our colleagues from the Time-Iono-GNSS group detected the event in their Solar Radio Burst warning system for GNSS.

Almost two hours after the Soft X-ray event, the radio type IV burst is still in progress, as shown by the spectra below taken from the real time observation page.

The whole event can be looked at here.