Solar U- and J-Bursts at the Decameter Waves

The first solar U- and J-bursts observed with the UTR-2 radiotelescope at the decameter wavelengths in 2003–2004 are reported. During that period more than 50 J-bursts and only 7 U-bursts were recorded. It is the first case of ground based observations of J- and U-bursts with turning frequencies ran...

Повний опис

Збережено в:
Бібліографічні деталі
Дата:2012
Автори: Dorovskyy, V. V., Melnik, V. M., Konovalenko, O. O., Rucker, H. O., Abranin, E. P., Lecacheux, A.
Формат: Стаття
Мова:rus
Опубліковано: Видавничий дім «Академперіодика» 2012
Онлайн доступ:http://rpra-journal.org.ua/index.php/ra/article/view/489
Теги: Додати тег
Немає тегів, Будьте першим, хто поставить тег для цього запису!
Назва журналу:Radio physics and radio astronomy

Репозитарії

Radio physics and radio astronomy
id oai:ri.kharkov.ua:article-489
record_format ojs
spelling oai:ri.kharkov.ua:article-4892012-11-16T12:11:13Z Solar U- and J-Bursts at the Decameter Waves Солнечные U- и J-всплески на декаметровых волнах Dorovskyy, V. V. Melnik, V. M. Konovalenko, O. O. Rucker, H. O. Abranin, E. P. Lecacheux, A. The first solar U- and J-bursts observed with the UTR-2 radiotelescope at the decameter wavelengths in 2003–2004 are reported. During that period more than 50 J-bursts and only 7 U-bursts were recorded. It is the first case of ground based observations of J- and U-bursts with turning frequencies ranging between 10 and 25 MHz. The harmonic structure of J-bursts in the form of Jb–J pairs similar to well known Type IIIb–III pairs was first found. The mean harmonic ratio appeared to be 1.8. Also a group of J-bursts with unusual Turning Frequency Drift (TFD) of –2 kHz/s was detected. Such TFD corresponds to the coronal loop elevation velocity of about 60 km/s. Coronal loops with similar elevation velocities were also detected by SOHO/LASCO coronagraph in white light. The dynamic spectra of unusual U- and J-bursts are shown. Simplified model of the coronal loop in the form of semi-circle was created on the base of the U-burst dynamic spectrum and the Newkirk coronal density model. With this loop model the linear velocity of the source along the loop, the height of the turning frequency point and the geometrical size of the loop were calculated. Приведены результаты первых наблюдений солнечных U- и J-всплесков на радиотелескопе УТР-2 в декаметровом диапазоне длин волн в 2003–2004 гг. За указанный период было зарегистрировано более 50 J-всплесков и только 7 U-всплесков. Это первый случай наземного наблюдения U-всплесков с частотами поворота в диапазоне между 10 и 25 МГц. Обнаружена гармоническая структура J-всплесков в виде Jb–J пар, аналогичных парам всплесков IIIb–III типа. Среднее отношение частот гармоник оказалось равным 1.8. Зарегистрирована группа J-всплесков с необычной скоростью дрейфа частот поворота (TFD) –2 кГц/с, что соответствует скорости подъема корональной арки около 60 км/с. Арки с такой скоростью подъема были обнаружены также коронографом SOHO/LASCO в видимом свете. Приведены динамические спектры необычных U- и J-всплесков. По динамическому спектру U-всплеска с хорошо развитыми восходящей и нисходящей ветвями построена упрощенная модель корональной арки в виде полуокружности. На основании этой модели найдены линейная скорость перемещения источника вдоль магнитной арки, высота точки поворота в короне, геометрические размеры арки. Видавничий дім «Академперіодика» 2012-11-14 Article Article application/pdf http://rpra-journal.org.ua/index.php/ra/article/view/489 РАДИОФИЗИКА И РАДИОАСТРОНОМИЯ; Vol 15, No 1 (2010); 5 RADIO PHYSICS AND RADIO ASTRONOMY; Vol 15, No 1 (2010); 5 РАДІОФІЗИКА І РАДІОАСТРОНОМІЯ; Vol 15, No 1 (2010); 5 2415-7007 1027-9636 rus http://rpra-journal.org.ua/index.php/ra/article/view/489/54
institution Radio physics and radio astronomy
collection OJS
language rus
format Article
author Dorovskyy, V. V.
Melnik, V. M.
Konovalenko, O. O.
Rucker, H. O.
Abranin, E. P.
Lecacheux, A.
spellingShingle Dorovskyy, V. V.
Melnik, V. M.
Konovalenko, O. O.
Rucker, H. O.
Abranin, E. P.
Lecacheux, A.
Solar U- and J-Bursts at the Decameter Waves
author_facet Dorovskyy, V. V.
Melnik, V. M.
Konovalenko, O. O.
Rucker, H. O.
Abranin, E. P.
Lecacheux, A.
author_sort Dorovskyy, V. V.
title Solar U- and J-Bursts at the Decameter Waves
title_short Solar U- and J-Bursts at the Decameter Waves
title_full Solar U- and J-Bursts at the Decameter Waves
title_fullStr Solar U- and J-Bursts at the Decameter Waves
title_full_unstemmed Solar U- and J-Bursts at the Decameter Waves
title_sort solar u- and j-bursts at the decameter waves
title_alt Солнечные U- и J-всплески на декаметровых волнах
description The first solar U- and J-bursts observed with the UTR-2 radiotelescope at the decameter wavelengths in 2003–2004 are reported. During that period more than 50 J-bursts and only 7 U-bursts were recorded. It is the first case of ground based observations of J- and U-bursts with turning frequencies ranging between 10 and 25 MHz. The harmonic structure of J-bursts in the form of Jb–J pairs similar to well known Type IIIb–III pairs was first found. The mean harmonic ratio appeared to be 1.8. Also a group of J-bursts with unusual Turning Frequency Drift (TFD) of –2 kHz/s was detected. Such TFD corresponds to the coronal loop elevation velocity of about 60 km/s. Coronal loops with similar elevation velocities were also detected by SOHO/LASCO coronagraph in white light. The dynamic spectra of unusual U- and J-bursts are shown. Simplified model of the coronal loop in the form of semi-circle was created on the base of the U-burst dynamic spectrum and the Newkirk coronal density model. With this loop model the linear velocity of the source along the loop, the height of the turning frequency point and the geometrical size of the loop were calculated.
publisher Видавничий дім «Академперіодика»
publishDate 2012
url http://rpra-journal.org.ua/index.php/ra/article/view/489
work_keys_str_mv AT dorovskyyvv solaruandjburstsatthedecameterwaves
AT melnikvm solaruandjburstsatthedecameterwaves
AT konovalenkooo solaruandjburstsatthedecameterwaves
AT ruckerho solaruandjburstsatthedecameterwaves
AT abraninep solaruandjburstsatthedecameterwaves
AT lecacheuxa solaruandjburstsatthedecameterwaves
AT dorovskyyvv solnečnyeuijvspleskinadekametrovyhvolnah
AT melnikvm solnečnyeuijvspleskinadekametrovyhvolnah
AT konovalenkooo solnečnyeuijvspleskinadekametrovyhvolnah
AT ruckerho solnečnyeuijvspleskinadekametrovyhvolnah
AT abraninep solnečnyeuijvspleskinadekametrovyhvolnah
AT lecacheuxa solnečnyeuijvspleskinadekametrovyhvolnah
first_indexed 2024-05-26T06:33:17Z
last_indexed 2024-05-26T06:33:17Z
_version_ 1800095869755719680