Search Publications

Observation-based modelling of magnetised coronal mass ejections with EUHFORIA
DOI: 10.1051/0004-6361/201935053 Bibcode: 2019A&A...626A.122S

Mierla, M.; Rodriguez, L.; Poedts, S. +2 more

Context. Coronal mass ejections (CMEs) are the primary source of strong space weather disturbances at Earth. Their geo-effectiveness is largely determined by their dynamic pressure and internal magnetic fields, for which reliable predictions at Earth are not possible with traditional cone CME models.
Aims: We study two well-observed Earth-dir…

2019 Astronomy and Astrophysics
SOHO 95
The evolution of coronal mass ejections in the inner heliosphere: Implementing the spheromak model with EUHFORIA
DOI: 10.1051/0004-6361/201834702 Bibcode: 2019A&A...627A.111V

Poedts, S.; Verbeke, C.; Pomoell, J.


Aims: We introduce a new model for coronal mass ejections (CMEs) that has been implemented in the magnetohydrodynamics (MHD) inner heliosphere model EUHFORIA. Utilising a linear force-free spheromak (LFFS) solution, the model provides an intrinsic magnetic field structure for the CME. As a result, the new model has the potential to predict th…

2019 Astronomy and Astrophysics
SOHO 81
Damping of slow magnetoacoustic oscillations by the misbalance between heating and cooling processes in the solar corona
DOI: 10.1051/0004-6361/201936072 Bibcode: 2019A&A...628A.133K

Nakariakov, V. M.; Kolotkov, D. Y.; Zavershinskii, D. I.

Context. Rapidly decaying slow magnetoacoustic waves are regularly observed in the solar coronal structures, offering a promising tool for a seismological diagnostics of the coronal plasma, including its thermodynamical properties.
Aims: The effect of damping of standing slow magnetoacoustic oscillations in the solar coronal loops is investig…

2019 Astronomy and Astrophysics
SOHO 67
Time-distance helioseismology of solar Rossby waves
DOI: 10.1051/0004-6361/201834849 Bibcode: 2019A&A...626A...3L

Gizon, Laurent; Liang, Zhi-Chao; Birch, Aaron C. +1 more

Context. Solar Rossby waves (r modes) have recently been discovered in the near-surface horizontal flow field using the techniques of granulation-tracking and ring-diagram analysis applied to six years of SDO/HMI data.
Aims: Here we apply time-distance helioseismology to the combined SOHO/MDI and SDO/HMI data sets, which cover 21 years of obs…

2019 Astronomy and Astrophysics
SOHO 61
Rotation rate of the solar core as a key constraint to magnetic angular momentum transport in stellar interiors
DOI: 10.1051/0004-6361/201935509 Bibcode: 2019A&A...626L...1E

Buldgen, G.; Eggenberger, P.; Salmon, S. J. A. J.

Context. The internal rotation of the Sun constitutes a fundamental constraint when modelling angular momentum transport in stellar interiors. In addition to the more external regions of the solar radiative zone probed by pressure modes, measurements of rotational splittings of gravity modes would offer an invaluable constraint on the rotation of …

2019 Astronomy and Astrophysics
SOHO 52
Variable emission mechanism of a Type IV radio burst
DOI: 10.1051/0004-6361/201834510 Bibcode: 2019A&A...623A..63M

Kilpua, E. K. J.; Monstein, C.; Morosan, D. E. +1 more

Context. The Sun is an active star and the source of the largest explosions in the solar system, such as flares and coronal mass ejections (CMEs). Flares and CMEs are powerful particle accelerators that can generate radio emission through various emission mechanisms.
Aims: CMEs are often accompanied by Type IV radio bursts that are observed a…

2019 Astronomy and Astrophysics
PROBA-2 SOHO 32
Combining multiple structural inversions to constrain the solar modelling problem
DOI: 10.1051/0004-6361/201833971 Bibcode: 2019A&A...621A..33B

Buldgen, G.; Eggenberger, P.; Meynet, G. +12 more

Context. The Sun is the most studied of all stars, which serves as a reference for all other observed stars in the Universe. Furthermore, it also serves the role of a privileged laboratory of fundamental physics and can help us better understand processes occuring in conditions irreproducible on Earth. However, our understanding of our star is cur…

2019 Astronomy and Astrophysics
SOHO 27
The EUV spectrum of the Sun: Quiet- and active-Sun irradiances and chemical composition
DOI: 10.1051/0004-6361/201834842 Bibcode: 2019A&A...624A..36D

Del Zanna, G.

We benchmark new atomic data against a selection of irradiances obtained from medium-resolution quiet-Sun spectra in the extreme ultraviolet (EUV), from 60 to 1040 Å. We used as a baseline the irradiances measured during solar minimum on 2008 April 14 by the prototype (PEVE) of the Solar Dynamics Observatory Extreme ultraviolet Variability Experim…

2019 Astronomy and Astrophysics
SOHO 24
From solar to stellar flare characteristics. On a new peak size distribution for G-, K-, and M-dwarf star flares
DOI: 10.1051/0004-6361/201832789 Bibcode: 2019A&A...621A..67H

Heber, Bernd; Papaioannou, Athanasios; Herbst, Konstantin +1 more

Context. The connection between solar energetic proton events and X-ray flares has been the focus of many studies over the past 13 yr. In the course of these investigations several peak size distribution functions based on Geostationary Operational Environmental Satellite (GOES) measurements of both quantities have been developed. In more recent s…

2019 Astronomy and Astrophysics
SOHO 23
Launch of a CME-associated eruptive prominence as observed with IRIS and ancillary instruments
DOI: 10.1051/0004-6361/201834259 Bibcode: 2019A&A...624A..72Z

Vial, J. -C.; Zhang, P.; Buchlin, É.


Aims: In this paper we focus on the possible observational signatures of the processes which have been put forward for explaining eruptive prominences. We also try to understand the variations in the physical conditions of eruptive prominences and estimate the masses leaving the Sun versus the masses returning to the Sun during eruptive promi…

2019 Astronomy and Astrophysics
IRIS SOHO 22