Solar-Terrestrial Physics Solar-Terrestrial Physics Solar-Terrestrial Physics 2500-0535 83396 10.12737/stp-103202401 19TH ANNUAL CONFERENCE “PLASMA PHYSICS IN THE SOLAR SYSTEM”. FEBRUARY 5–9, 2024, SPACE RESEARCH INSTITUTE RAS, MOSCOW, RUSSIA 19TH ANNUAL CONFERENCE “PLASMA PHYSICS IN THE SOLAR SYSTEM”. FEBRUARY 5–9, 2024, SPACE RESEARCH INSTITUTE RAS, MOSCOW, RUSSIA 19TH ANNUAL CONFERENCE “PLASMA PHYSICS IN THE SOLAR SYSTEM”. FEBRUARY 5–9, 2024, SPACE RESEARCH INSTITUTE RAS, MOSCOW, RUSSIA Observations of coronal holes with the Siberian Radioheliograph Observations of coronal holes with the Siberian Radioheliograph https://orcid.org/0000-0002-1589-556X Алтынцев Александр Тимофеевич Altyntsev Alexander Timofeevich

доктор физико-математических наук;

doctor of physical and mathematical sciences;

 https://orcid.org/0000-0001-9174-7350 Глоба Мария Викторовна Globa Mariia Viktorovna globa@iszf.irk.ru

аспирант физико-математических наук;

graduate student of physical and mathematical sciences;

 https://orcid.org/0000-0002-6873-6394 Мешалкина Наталия Сергеевна Meshalkina Nataliya Sergeevna nata@iszf.irk.ru

кандидат физико-математических наук;

candidate of physical and mathematical sciences;

 Сыч Роберт Андреевич Sych Robert Andreevich sych@iszf.irk.ru

кандидат физико-математических наук;

candidate of physical and mathematical sciences;

 Институт солнечно-земной физики СО РАН Иркутск Россия Institute of Solar Terrestrial Physics SB RAS Irkutsk Russian Federation Институт солнечно-земной физики СО РАН Иркутск Россия Institute of Solar-Terrestrial Physics SB RAS Irkutsk Russian Federation Институт солнечно-земной физики СО РАН Иркутск Россия Institute of Solar Terrestrial Physics SB RAS Irkutsk Russian Federation Институт солнечно-земной физики СО РАН Иркутск Россия Institute of Solar Terrestrial Physics SB RAS Irkutsk Russian Federation 29 09 2024 29 09 2024 10 3 3 10 04 02 2024 23 05 2024 https://naukaru.ru/en/nauka/article/83396/view

Multi-wavelength observations of a coronal hole (CH) with two-dimensional spatial resolution have been made for the first time in the frequency range from 2.8 to 12 GHz. At frequencies below 6 GHz, the average brightness of the hole is 1.5 times lower than the brightness level of the quiet Sun. The distribution of radio brightness over the hole is inhomogeneous: the ratio of maximum to minimum brightness temperatures falls from several times at low frequencies to tenths of fractions at the upper received frequencies. At frequencies above 6 GHz, the temperature contrast between the CH and regions of the quiet Sun is small. Within the CH, there are compact sources that are bright relative to the quiet Sun. In general, observations of CHs with SRH are promising both for the research into the nature of CHs and for the applied problems of forecasting solar wind characteristics.

Multi-wavelength observations of a coronal hole (CH) with two-dimensional spatial resolution have been made for the first time in the frequency range from 2.8 to 12 GHz. At frequencies below 6 GHz, the average brightness of the hole is 1.5 times lower than the brightness level of the quiet Sun. The distribution of radio brightness over the hole is inhomogeneous: the ratio of maximum to minimum brightness temperatures falls from several times at low frequencies to tenths of fractions at the upper received frequencies. At frequencies above 6 GHz, the temperature contrast between the CH and regions of the quiet Sun is small. Within the CH, there are compact sources that are bright relative to the quiet Sun. In general, observations of CHs with SRH are promising both for the research into the nature of CHs and for the applied problems of forecasting solar wind characteristics.

 Sun radio emission bremsstrahlung coronal holes Sun radio emission bremsstrahlung coronal holes The work was financially supported by RSF (Grant No. 22-22-00019). The study was carried out with the financial support from the Ministry of Science and Higher Education of the Russian Federation with budgetary funding of Program II.16.3.2 "Nonstationary and Wave Processes in the Solar Atmosphere" The work was financially supported by RSF (Grant No. 22-22-00019). The study was carried out with the financial support from the Ministry of Science and Higher Education of the Russian Federation with budgetary funding of Program II.16.3.2 "Nonstationary and Wave Processes in the Solar Atmosphere"

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