Solar powerful short-term flare in NOAA12628 at 3-4 GHz on 25 Jan 2017, 10:16:43 UT
ATel #10011; V. M. Bogod, T. I. Kaltman, A. A. Pervakov, Yu. V. Sotnikova, S. A. Trushkin (SAO RAS, Russia)
on 27 Jan 2017; 13:32 UT
Credential Certification: Sergei Trushkin (satr@sao.ru)
Subjects: Radio, Millimeter, Optical, The Sun
The unusual solar powerful short-term flare in the active region NOAA12628 was detected at the frequencies: 3.094, 3.281, 3.469, and 3.844 GHz on 25 Jan 2017 (10:16:43 UT) in regular solar observations with the RATAN-600 radio telescope. We use a regime of drift scanning in some azimuths around local solar culmination and the 80-channel spectral-polarimetric solar analyzer (3-18 GHz) to measure radio fluxes simultaneously from the common microwave horn. The brightness of the active area increased in 10 times from a level of quiet Sun (see our forecast system
PROGNOZ ), while brightness at high frequencies stayed usual (see total scans). The changes of the sign of circular polarization were measured, indicating the propagation of radio emission through a complex structure of magnetic field in solar corona. This unusual flare was not detected by the well-known solar monitoring service
Solar Monitor using the GOES satellite.
The RATAN drift scans at 3.094 GHz of intensity and circular polarization 25 Jan 2017