Search Publications

The first widespread solar energetic particle event of solar cycle 25 on 2020 November 29. Shock wave properties and the wide distribution of solar energetic particles
DOI: 10.1051/0004-6361/202142515 Bibcode: 2022A&A...660A..84K

Lario, D.; Vainio, R.; Kilpua, E. K. J. +13 more

Context. On 2020 November 29, an eruptive event occurred in an active region located behind the eastern solar limb as seen from Earth. The event consisted of an M4.4 class flare, a coronal mass ejection, an extreme ultraviolet (EUV) wave, and a white-light (WL) shock wave. The eruption gave rise to the first widespread solar energetic particle (SE…

2022 Astronomy and Astrophysics
SOHO SolarOrbiter 32
The relativistic solar particle event on 28 October 2021: Evidence of particle acceleration within and escape from the solar corona
DOI: 10.1051/0004-6361/202243903 Bibcode: 2022A&A...663A.173K

Krucker, Säm; Dresing, Nina; Klein, Karl-Ludwig +6 more


Aims: We analyse particle, radio, and X-ray observations during the first relativistic proton event of solar cycle 25 detected on Earth. The aim is to gain insight into the relationship between relativistic solar particles detected in space and the processes of acceleration and propagation in solar eruptive events.
Methods: To this end, …

2022 Astronomy and Astrophysics
SOHO SolarOrbiter 32
Flux rope and dynamics of the heliospheric current sheet. Study of the Parker Solar Probe and Solar Orbiter conjunction of June 2020
DOI: 10.1051/0004-6361/202142381 Bibcode: 2022A&A...659A.110R

Fedorov, A.; Parenti, S.; Lavraud, B. +19 more

Context. Solar Orbiter and Parker Solar Probe jointly observed the solar wind for the first time in June 2020, capturing data from very different solar wind streams: calm, Alfvénic wind and also highly dynamic large-scale structures. Context. Our aim is to understand the origin and characteristics of the highly dynamic solar wind observed by the t…

2022 Astronomy and Astrophysics
SolarOrbiter 30
Solar coronal heating from small-scale magnetic braids
DOI: 10.1051/0004-6361/202244170 Bibcode: 2022A&A...667A.166C

Barczynski, K.; Peter, H.; Chitta, L. P. +19 more

Relaxation of braided coronal magnetic fields through reconnection is thought to be a source of energy to heat plasma in active region coronal loops. However, observations of active region coronal heating associated with an untangling of magnetic braids remain sparse. One reason for this paucity could be the lack of coronal observations with a suf…

2022 Astronomy and Astrophysics
Hinode SolarOrbiter 30
The magnetic drivers of campfires seen by the Polarimetric and Helioseismic Imager (PHI) on Solar Orbiter
DOI: 10.1051/0004-6361/202142873 Bibcode: 2022A&A...660A.143K

Schmidt, W.; Woch, J.; Peter, H. +56 more

Context. The Extreme Ultraviolet Imager (EUI) on board the Solar Orbiter (SO) spacecraft observed small extreme ultraviolet (EUV) bursts, termed campfires, that have been proposed to be brightenings near the apexes of low-lying loops in the quiet-Sun atmosphere. The underlying magnetic processes driving these campfires are not understood.
Aim…

2022 Astronomy and Astrophysics
SolarOrbiter 29
What drives decayless kink oscillations in active-region coronal loops on the Sun?
DOI: 10.1051/0004-6361/202244403 Bibcode: 2022A&A...666L...2M

Teriaca, Luca; Solanki, Sami K.; Long, David M. +19 more

Here, we present a study of the phenomena of decayless kink oscillations in a system of active-region (AR) coronal loops. Using high-resolution observations from two different instruments, namely the Extreme Ultraviolet Imager (EUI) on board Solar Orbiter and the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory, we follow…

2022 Astronomy and Astrophysics
SolarOrbiter 27
Prominence eruption observed in He II 304 Å up to >6 R by EUI/FSI aboard Solar Orbiter
DOI: 10.1051/0004-6361/202244020 Bibcode: 2022A&A...662L...5M

Heinzel, P.; Mierla, M.; Zhukov, A. N. +24 more


Aims: We report observations of a unique, large prominence eruption that was observed in the He II 304 Å passband of the Extreme Ultraviolet Imager/Full Sun Imager telescope aboard Solar Orbiter on 15-16 February 2022.
Methods: Observations from several vantage points - Solar Orbiter, the Solar-Terrestrial Relations Observatory, the Sola…

2022 Astronomy and Astrophysics
SOHO SolarOrbiter 21
Forward fitting STIX visibilities
DOI: 10.1051/0004-6361/202243907 Bibcode: 2022A&A...668A.145V

Volpara, Anna; Massa, Paolo; Krucker, Säm +6 more


Aims: We seek to determine to what extent the problem of forward fitting visibilities measured by the Spectrometer/Telescope Imaging X-rays (STIX) on board Solar Orbiter becomes more challenging with respect to the same problem in the case of previous hard X-ray solar imaging missions. In addition, we aim to identify an effective optimization…

2022 Astronomy and Astrophysics
SolarOrbiter 20
Modeling the 2020 November 29 solar energetic particle event using EUHFORIA and iPATH models
DOI: 10.1051/0004-6361/202244732 Bibcode: 2022A&A...668A..71D

Li, Gang; Poedts, Stefaan; Ding, Zheyi +1 more


Aims: We present the implementation of a coupling between EUropean Heliospheric FORcasting Information Asset (EUHFORIA) and improved Particle Acceleration and Transport in the Heliosphere (iPATH) models. In this work, we simulate the widespread solar energetic particle (SEP) event of 2020 November 29 and compare the simulated time-intensity p…

2022 Astronomy and Astrophysics
SOHO SolarOrbiter 16
Coronal mass ejection followed by a prominence eruption and a plasma blob as observed by Solar Orbiter
DOI: 10.1051/0004-6361/202243162 Bibcode: 2022A&A...665A...7B

Heinzel, P.; Mierla, M.; Zhukov, A. N. +26 more

Context. On 2021 February 12, two subsequent eruptions occurred above the western limb of the Sun, as seen along the Sun-Earth line. The first event was a typical slow coronal mass ejection (CME), followed ∼7 h later by a smaller and collimated prominence eruption, originating south of the CME, followed by a plasma blob. These events were observed…

2022 Astronomy and Astrophysics
SOHO SolarOrbiter 16