Fine structures of a solar type III radio bursts observed with LOFAR
: Dabrowski, Bartosz; Wolowska, Aleksandra; Vocks, Christian; Magdalenić, Jasmina; Zhang, Peijin; Flisek, Pawel; Bröse, Malte; Morosan, Diana E.; Krankowski, Andrzej; Fron, Adam; Mann, Gottfried; Zucca, Pietro; Bisi, Mario; Fallows, Richard; Gallagher, Peter; Marqué, Christophe; Matyjasiak, Barbara; Rothkaehl, Hanna
Publisher: SPRINGER INT PUBL AG
: CHAM
: 2025
: Acta Geophysica
: ACTA GEOPHYSICA
: ACTA GEOPHYS
: 73
: 1
: 987
: 993
: 7
: 1895-6572
: 1895-7455
DOI: https://doi.org/10.1007/s11600-024-01421-4
: https://doi.org/10.1007/s11600-024-01421-4
: https://research.utu.fi/converis/portal/detail/Publication/457640785
: Publisher Correction to this article: https://doi.org/10.1007/s11600-024-01461-w ; DOI:10.1007/s11600-024-01461-w
We present spectral and imaging LOFAR (LOw-Frequency ARray) observations in the 20 – 40 MHz range of solar radio bursts fne structures, such as fag-like, sail-like, and dot-like that appeared on 8 April 2019. These structures were associated with type III solar radio bursts that occurred in the 40 – 80 MHz band. The mean duration and spectral widths of the fne structures range from 1.0 to 3.4 s and from 0.3 to 0.9 MHz, respectively. Additionally, we investigated the radio images of eight fne structures – two fags, two sails and four dots. This allowed us to determine their emission source sizes, which ranged from 240 to 392 arcmin2, and their frequencies from 25.58 to 39.25 MHz as well as their location. They occurred on the east side of the Sun and were most likely associated with an emerging active region NOAA AR 12738, where a weak B1.7 fare was observed.
:
We acknowledge the National Science Centre, Poland and the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) for granting “LOFAR observations of the solar corona during Parker Solar Probe perihelion passages” in the Beethoven Classic 3 funding initiative under project numbers 2018/31/G/ST9/01341 and VO 2123/1-1, respectively. UWM would like to thank the Ministry of Education and Science of Poland for granting funds for the Polish contribution to the International LOFAR Telescope, LOFAR2.0 upgrade (decision number: 2021/WK/2) and for maintenance of the LOFAR PL-612 Bałdy station (decision number: 28/530020/SPUB/SP/2022). Diana E. Morosan acknowledges the Research Council of Finland project SolShocks (grant number: 354409). The authors thank the KSP “Solar Physics and Space Weather with LOFAR” team for support in solar LOFAR research. This paper is based on data obtained with the International LOFAR Telescope (ILT) under project code LT10_002. LOFAR (van Haarlem et al. 2013) is the Low Frequency Array designed and constructed by ASTRON. It has observing, data processing, and data storage facilities in several countries that are owned by various parties (each with their own funding sources), and that are collectively operated by the ILT foundation under a joint scientific policy. The ILT resources have benefited from the following recent major funding sources: CNRS-INSU, Observatoire de Paris and Université d’Orléans, France; BMBF, MIWF-NRW, MPG, Germany; Science Foundation Ireland (SFI), Department of Business, Enterprise and Innovation (DBEI), Ireland; NWO, The Netherlands; The Science and Technology Facilities Council, UK; Ministry of Science and Higher Education, Poland. The AIA data from SDO satellite are courtesy of NASA.
