LOFAR observations of the solar corona during Parker Solar Probe perihelion passages

• Applicant: Dr. Christian Vocks
• Subject Area: Astrophysics and Astronomy
• Term: from 2019 to 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 426501369

• Final Report Year: 2024

Final Report Abstract

The phenomena of the active Sun, like flares and coronal mass ejections (CMEs), release energetic particles and plasma clouds into the heliosphere. The influence of these on Earth and its space environment is usually called “Space Weather”. Energetic electrons cause radio emission along their path through the solar corona, that is observable with radio telescopes like the LOw Frequency ARray (LOFAR). In order to better understand their acceleration and release mechanism into the heliosphere, the LOFAR Key Science Project “Solar Physics and Space Weather with LOFAR” has organized joint observation campaigns during the perihelia of the Parker Solar Probe (PSP) and Solar Orbiter spacecraft that are currently exploring the inner heliosphere. This project focused on the analysis of these data. It covers different aspects, like type III radio bursts caused by energetic electron beams, that are imaged and spectroscopically observed with LOFAR, or type II bursts as signatures of electron acceleration at coronal shocks associated with the launch of coronal mass ejections (CMEs). For this project a postdoc was hired to model electron acceleration at coronal shock waves and to reconstruct spectral characteristics of type II radio bursts, like frequency evolution as a shock propagates along a given magnetic field line, and intensity variations as the efficiency of electron acceleration changes. These studies aim at explaining observed features in type II burst dynamic spectra. A PhD student worked on type III burst activity and the thermal evolution of solar coronal loops during weak solar flares. He performed a multi-wavelength study, including X-ray data from the STIX telescope on the Solar Orbiter spacecraft and LOFAR observations, and combined them with EUV images from the Solar Dynamics Observatory satellite. A Differential Emission Measure analysis reveals the temperature evolution of coronal loops during the flare, while magnetic field extrapolations from the photosphere into the middle and higher corona provide the connection to source positions observed by LOFAR. This way it is possible to distinguish whether variations in type III activity are due to changing electron acceleration efficiency or due to varying magnetic connectivity to the flare site. Furthermore, a student assistant worked with Solar Orbiter and PSP particle detector data. The software packages he developed form the basis for a master thesis currently being prepared at AIP, aiming at combining these with LOFAR and spacecraft radio data to study energetic electron acceleration and release. Another master thesis was motivated by the type III studies of the PhD student and our Polish project partners. The joint observing campaigns have been continued during the project, and data analysis is an ongoing effort.

Publications

• 16th European Solar Physics Meeting, 6 – 10 September 2021 (online): LOFAR observations of fundamental and harmonic type III emission during an M class flare
  Vocks, Christian
  
• Fine Structure of a Solar Type II Radio Burst Observed by LOFAR. The Astrophysical Journal Letters, 897(1), L15.
  Magdalenić, Jasmina; Marqué, Christophe; Fallows, Richard A.; Mann, Gottfried; Vocks, Christian; Zucca, Pietro; Dabrowski, Bartosz P.; Krankowski, Andrzej & Melnik, Valentin
  
• Interferometric imaging with LOFAR remote baselines of the fine structures of a solar type-IIIb radio burst. Astronomy & Astrophysics, 639, A115.
  Zhang, PeiJin; Zucca, Pietro; Sridhar, Sarrvesh Seethapuram; Wang, ChuanBing; Bisi, Mario M.; Dabrowski, Bartosz; Krankowski, Andrzej; Mann, Gottfried; Magdalenic, Jasmina; Morosan, Diana E. & Vocks, Christian
  
• Radio 2020 & GLOW Assembly, 12 – 14 October 2020, Garching (online): M-class flare radio source evolution observed by LOFAR
  Vocks, Christian
  
• The Frequency Drift and Fine Structures of Solar S-bursts in the High Frequency Band of LOFAR. The Astrophysical Journal, 891(1), 89.
  Zhang, PeiJin; Zucca, Pietro; Wang, ChuanBing; Bisi, Mario M.; Da̧browski, Bartosz; Fallows, Richard A.; Krankowski, Andrzej; Magdalenic, Jasmina; Mann, Gottfried; Morosan, Diana E. & Vocks, Christian
  
• Tuning the Exospace Weather Radio for Stellar Coronal Mass Ejections. The Astrophysical Journal, 895(1), 47.
  Alvarado-Gómez, Julián D.; Drake, Jeremy J.; Fraschetti, Federico; Garraffo, Cecilia; Cohen, Ofer; Vocks, Christian; Poppenhäger, Katja; Moschou, Sofia P.; Yadav, Rakesh K. & Manchester, IV Ward B.
  
• 16th European Solar Physics Meeting, 6 – 10 September 2021 (online): Type III solar radio event observations on 22 August 2017 with LOFAR telescope
  Dabrowski, Bartosz
  
• 5. Nationaler Weltraumwetterworkshop, 21 September 2021 DLR Neustrelitz (onlline): Solar radio observations with LOFAR and space weather applications
  Vocks, Christian
  
• LOFAR imaging of the solar corona during the 2015 March 20 solar eclipse. Astronomy & Astrophysics, 648, A43.
  Ryan, A. M.; Gallagher, P. T.; Carley, E. P.; Brentjens, M. A.; Murphy, P. C.; Vocks, C.; Morosan, D. E.; Reid, H.; Magdalenic, J.; Breitling, F.; Zucca, P.; Fallows, R.; Mann, G.; Kerdraon, A. & Halfwerk, R.
  
• Radio 2021 & GLOW Assembly, 22 – 24 November 2021, Garching: LOFAR observations of fundamental and harmonic type III emission during an M class flare
  Vocks, Christian
  
• RHESSI-20 Workshop, 6 – 9 July 2021, Pisa, Italy (online): SLOFAR observations of fundamental and harmonic type III emission during an M class flare
  Vocks, Christian
  
• RHESSI-20 Workshop, 6 – 9 July 2021, Pisa, Italy (online): Temperature and Differential Emission Measure Evolution of a Limb Flare on 13 January 2015
  Bröse, Malte
  
• Type III Radio Bursts Observations on 20th August 2017 and 9th September 2017 with LOFAR Bałdy Telescope. Remote Sensing, 13(1), 148.
  Dabrowski, Bartosz; Flisek, Paweł; Mikuła, Katarzyna; Froń, Adam; Vocks, Christian; Magdalenić, Jasmina; Krankowski, Andrzej; Zhang, PeiJin; Zucca, Pietro & Mann, Gottfried
  
• URSI GASS 2021, 28 August – 4 September 2021, Rome, Italy (online): Solar radio observations with LOFAR and space weather applications
  Vocks, Christian
  
• URSI GASS 2021, 28 August – 4 September 2021, Rome, Italy (online): Temperature and Differential Emission Measure Evolution of a Limb Flare on 13 January 2015
  Bröse, Malte
  
• Exploring the Circular Polarisation of Low–Frequency Solar Radio Bursts with LOFAR. Solar Physics, 297(4).
  Morosan, Diana E.; Räsänen, Juska E.; Kumari, Anshu; Kilpua, Emilia K. J.; Bisi, Mario M.; Dabrowski, Bartosz; Krankowski, Andrzej; Magdalenić, Jasmina; Mann, Gottfried; Rothkaehl, Hanna; Vocks, Christian & Zucca, Pietro
  
• Imaging of the Quiet Sun in the Frequency Range of 20–80 MHz. The Astrophysical Journal, 932(1), 17.
  Zhang, 张沛 PeiJin 锦; Zucca, Pietro; Kozarev, Kamen; Carley, Eoin; Wang, 王传 ChuanBing 兵; Franzen, Thomas; Dabrowski, Bartosz; Krankowski, Andrzej; Magdalenic, Jasmina & Vocks, Christian
  
• Interpretation of Radio Wave Scintillation Observed through LOFAR Radio Telescopes. The Astrophysical Journal Supplement Series, 263(2), 36.
  Forte, Biagio; Fallows, Richard A.; Bisi, Mario M.; Zhang, Jinge; Krankowski, Andrzej; Dabrowski, Bartosz; Rothkaehl, Hanna & Vocks, Christian
  
• Lensing from small-scale travelling ionospheric disturbances observed using LOFAR. Journal of Space Weather and Space Climate, 12, 34.
  Boyde, Ben; Wood, Alan; Dorrian, Gareth; Fallows, Richard A.; Themens, David; Mielich, Jens; Elvidge, Sean; Mevius, Maaijke; Zucca, Pietro; Dabrowski, Bartosz; Krankowski, Andrzej; Vocks, Christian & Bisi, Mario
  
• LOFAR Family Meeting 2022, 13 – 17 June 2022, Köln: First joint STIX and LOFAR Observations of a Flare Event on 6 June 2020
  Bröse, Malte
  
• LOFAR Family Meeting 2022, 13 – 17 June 2022, Köln: Interferometric imaging of the type IIIb radio bursts observed with LOFAR on 22 August 2017
  Dabrowski, Bartosz
  
• LOFAR Family Meeting 2022, 13 – 17 June 2022, Köln: Separating fundamental and harmonic sources in LOFAR solar type III radio burst images
  Vocks, Christian
  
• LOFAR Family Meeting 2022, 13 – 17 June 2022, Köln: Simulations of type II solar radio bursts to interpret LOFAR observations
  Wu, Y.
  
• Pulsar scintillation studies with LOFAR. Astronomy & Astrophysics, 663, A116.
  Wu, Ziwei; Verbiest, Joris P. W.; Main, Robert A.; Grießmeier, Jean-Mathias; Liu, Yulan; Osłowski, Stefan; Moochickal, Ambalappat Krishnakumar; Nielsen, Ann-Sofie Bak; Künsemöller, Jörn; Donner, Julian Y.; Tiburzi, Caterina; Porayko, Nataliya; Serylak, Maciej; Künkel, Lars; Brüggen, Marcus & Vocks, Christian
  
• Radio 2022 and GLOW Annual Assembly, 2 – 4 November 2022, Berlin: Fundamental-harmonic source pairs in in LOFAR solar type III radio burst images
  Vocks, Christian
  
• Solar Orbiter Summer School 2022, 30 May – 3 June 2022, Sète, France: First joint STIX and LOFAR Observations of a Flare Event on 6 June 2020
  Bröse, Malte
  
• Solar Physics High Energy Research (SPHERE) Workshop, 11 - 15 July 2022, Windisch, Switzerland: Temperature and differential emission measure evolution of a limb flare on 13 January 2015
  Bröse, Malte
  
• The Kinetic Expansion of Solar-wind Electrons: Transport Theory and Predictions for the Very Inner Heliosphere. The Astrophysical Journal, 927(2), 162.
  Jeong, Seong-Yeop; Verscharen, Daniel; Vocks, Christian; Abraham, Joel B.; Owen, Christopher J.; Wicks, Robert T.; Fazakerley, Andrew N.; Stansby, David; Berčič, Laura; Nicolaou, Georgios; Agudelo, Rueda Jeffersson A. & Bakrania, Mayur
  
• Type III radio bursts and excitation of Langmuir waves by energetic electrons. Astronomy & Astrophysics, 660, A91.
  Mann, G.; Vocks, C. & Warmuth, A.
  
• URSI Kleinheubacher Tagung 2022, 27 – 29 September 2022: Exploring the inner heliosphere with combined LOFAR and Solar Orbiter / Parker Solar Probe observations
  Vocks, Christian
  
• CESRA Workshop 2023, 3 – 7 July 2023, University of Hertfordshire, UK: bservations of the Sun and heliosphere using LOFAR for a coordinated ground- and space-based approach to Space-Weather research.
  Zucca, Pietro
  
• CESRA Workshop 2023, 3 – 7 July 2023, University of Hertfordshire, UK: Flare-accelerated electrons and the thermal evolution of the associated active region
  Bröse, Malte
  
• CESRA Workshop 2023, 3 – 7 July 2023, University of Hertfordshire, UK: Separating fundamental and harmonic sources in LOFAR solar type III radio burst images
  Vocks, Christian
  
• DPG – Frühjahrstagung 2023, 20 – 24 March 2023, Dresden: Exploring the inner heliosphere with combined LOFAR and Solar Orbiter / Parker Solar Probe observations
  Vocks, Christian
  
• DPG – Frühjahrstagung 2023, 20 – 24 March 2023, Dresden: Joint LOFAR and STIX observations of flare-accelerated electrons in the solar corona
  Bröse, Malte
  
• EGU General Assembly 2023, 23 – 28 April 2023, Vienna, Austria: Flare-accelerated electrons and their traces in the solar corona observed by space- and ground-based instruments
  Bröse, Malte
  
• EGU General Assembly 2023, 23 – 28 April 2023, Vienna, Austria: Separating fundamental and harmonic sources in LOFAR solar type III radio burst images
  Vocks, Christian
  
• Interferometric imaging of the type IIIb and U radio bursts observed with LOFAR on 22 August 2017. Astronomy & Astrophysics, 669, A52.
  Dabrowski, Bartosz; Mikuła, Katarzyna; Flisek, Paweł; Vocks, Christian; Zhang, PeiJin; Magdalenić, Jasmina; Warmuth, Alexander; Morosan, Diana E.; Froń, Adam; Fallows, Richard A.; Bisi, Mario M.; Krankowski, Andrzej; Mann, Gottfried; Błaszkiewicz, Leszek; Carley, Eoin P.; Gallagher, Peter T.; Zucca, Pietro; Rudawy, Paweł; Hajduk, Marcin ... & Sidorowicz, Tomasz
  
• LOFAR Family Meeting, 12 – 16 June 2023, Olsztyn, Poland: Flare-accelerated electrons and the thermal evolution of the associated active region
  Bröse, Malte
  
• LOFAR Family Meeting, 12 – 16 June 2023, Olsztyn, Poland: Fundamental and harmonic emission in LOFAR solar type III radio burst images
  Vocks, Christian
  
• LOFAR Family Meeting, 12 – 16 June 2023, Olsztyn, Poland:The solar radio bursts observations with LOFAR
  Dabrowski, Bartosz
  
• LOFAR Family Meeting, 3 – 7 June 2023, Leiden, Netherlands: Evolution of fundamental and harmonic sources in LOFAR type III radio burst images
  Vocks, Christian
  
• LOFAR Family Meeting, 3 – 7 June 2023, Leiden, Netherlands: Solar research with LOFAR telescope (invited)
  Dabrowski, Bartosz
  
• LOFAR Observations of Substructure Within a Traveling Ionospheric Disturbance at Mid‐Latitude. Space Weather, 21(1).
  Dorrian, Gareth; Fallows, Richard; Wood, Alan; Themens, David R.; Boyde, Ben; Krankowski, Andrzej; Bisi, Mario; Dąbrowski, Bartosz & Vocks, Christian
  
• Radio 2023, 14 – 17 November 2023, Bochum: Fundamental and harmonic emission in LOFAR solar type III radio burst images
  Vocks, Christian
  
• Solar Physics High Energy Research (SPHERE) Workshop, 20 – 23 June 2023, Maryland, USA: Flare-accelerated electrons and the thermal evolution of the associated active region
  Bröse, Malte
  
• Towards the possibility to combine LOFAR and GNSS measurements to sense ionospheric irregularities. Journal of Space Weather and Space Climate, 13, 27.
  Flisek, Paweł; Forte, Biagio; Fallows, Richard; Kotulak, Kacper; Krankowski, Andrzej; Bisi, Mario; Mevius, Maaijke; Froń, Adam; Tiburzi, Caterina; Soida, Marian; Śmierciak, Bartosz; Grzesiak, Marcin; Matyjasiak, Barbara; Pożoga, Mariusz; Dąbrowski, Bartosz; Mann, Gottfried; Vocks, Christian; Zucca, Pietro & Błaszkiewicz, Leszek
  
• URSI GASS 2023, 19 – 26 August 2023, Sapporo, Japan: Separating fundamental and harmonic sources in LOFAR solar type III radio burst images
  Vocks, Christian
  
• URSI Kleinheubacher Tagung 2023, 26 – 28 September 2023: Fundamental and harmonic emission in LOFAR solar type III radio burst images
  Vocks, Christian
  
• URSI Kleinheubacher Tagung 2023, 26 – 28 September 2023: Solar radiation studied with LOFAR
  Dabrowski, Bartosz
  
• DPG – Frühjahrstagung 2024, 26 – 29 February 2024, Greifswald: Separating fundamental and harmonic emission in LOFAR solar type III radio burst images
  Vocks, Christian
  
• Fine structures of a solar type III radio bursts observed with LOFAR. Acta Geophysica, 73(1), 987-993.
  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
  
• Imaging spectroscopy of a spectral bump in a type II radio burst. Astronomy & Astrophysics, 684, L22.
  Zhang, Peijin; Morosan, Diana E.; Zucca, Pietro; Normo, Sanna; Dabrowski, Bartosz; Krankowski, Andrzej & Vocks, Christian