In several papers the thermal conduction front formed between hot and cold plasmas was studied (Brown et al. 1979, McKean et al 1990, Arber & Melnikov 2009). Karlický (2015) has studied the thermal front using a 3-D particle-in-cell electromagnetic code and found that the thermal front can produce radio emission. Here we present a very rare radio burst which we interpreted as generated by the thermal conduction front formed in front of the falling EUV blob.
Figure 1. Radio spectrum observed during the 2015 November 4 flare by the Ondřejov radiospectrograph. The arrow shows the SPDB.
Figure 1 shows the 800 – 2000 MHz radio spectrum of the M3.7 flare observed on 2015-Nov-04 by the Ondřejov radiospectrograph. In this radio spectrum a very rare slowly positively drifting burst (SPDB) can be seen. It started at 1300 MHz at 13:40:24 UT and drifted towards higher frequencies with frequency drift of about 115 MHz s-1. The SPDB was observed during the impulsive phase of the flare, close to the maximum peak of GOES soft X-rays derivatives. We used data from several instruments (SDO/AIA, Hinode/XRT, IRIS, MSDP/Bialkow). We analysed these to find any observable EUV signatures associated with the SPDB. Figure 2 ...