Astronomy & Astrophysics (A&A)

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³He-rich solar energetic particle events observed on the first perihelion pass of Solar Orbiter

G. M. Mason, G. C. Ho, R. C. Allen, J. Rodríguez-Pacheco, R. F. Wimmer-Schweingruber, R. Bučík, R. Gómez-Herrero, D. Lario, J. L. F. von Forstner, G. B. Andrews et al. (12 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202039752

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Suprathermal particles from corotating interaction regions during the first perihelion pass of Solar Orbiter

R. C. Allen, G. M. Mason, G. C. Ho, J. Rodríguez-Pacheco, R. F. Wimmer-Schweingruber, G. B. Andrews, L. Berger, S. Boden, I. Cernuda, F. Espinosa Lara et al. (17 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202039870

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First near-relativistic solar electron events observed by EPD onboard Solar Orbiter

R. Gómez-Herrero, D. Pacheco, A. Kollhoff, F. Espinosa Lara, J. L. Freiherr von Forstner, N. Dresing, D. Lario, L. Balmaceda, V. Krupar, O. E. Malandraki et al. (54 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202039883

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Extreme-UV quiet Sun brightenings observed by the Solar Orbiter/EUI

D. Berghmans, F. Auchère, D. M. Long, E. Soubrié, M. Mierla, A. N. Zhukov, U. Schühle, P. Antolin, L. Harra, S. Parenti et al. (18 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140380

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Quiet-time low energy ion spectra observed on Solar Orbiter during solar minimum

G. M. Mason, G. C. Ho, R. C. Allen, Z. G. Xu, N. P. Janitzek, J. L. Freiherr von Forstner, A. Kohllhoff, D. Pacheco, J. Rodríguez-Pacheco, R. F. Wimmer-Schweingruber et al. (25 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140540

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Solar origins of a strong stealth CME detected by Solar Orbiter

Jennifer O’Kane, Lucie M. Green, Emma E. Davies, Christian Möstl, Jürgen Hinterreiter, Johan L. Freiherr von Forstner, Andreas J. Weiss, David M. Long and Tanja Amerstorfer

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140622

Press Release

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Transient small-scale brightenings in the quiet solar corona: A model for campfires observed with Solar Orbiter

Yajie Chen, Damien Przybylski, Hardi Peter, Hui Tian, F. Auchère and D. Berghmans

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140638

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Solar Orbiter observations of the structure of reconnection outflow layers in the solar wind

C. J. Owen, A. C. Foster, R. Bruno, S. Livi, P. Louarn, M. Berthomier, A. Fedorov, C. Anekallu, D. Kataria, C. W. Kelly et al. (15 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140944

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High-cadence measurements of electron pitch-angle distributions from Solar Orbiter SWA-EAS burst mode operations

C. J. Owen, D. O. Kataria, L. Berčič, T. S. Horbury, M. Berthomier, D. Verscharen, R. Bruno, S. Livi, P. Louarn, C. Anekallu et al. (10 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140959

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Evidence for local particle acceleration in the first recurrent galactic cosmic ray depression observed by Solar Orbiter - The ion event on 19 June 2020

A. Aran, D. Pacheco, M. Laurenza, N. Wijsen, D. Lario, S. Benella, I. G. Richardson, E. Samara, J. L. Freiherr von Forstner, B. Sanahuja et al. (54 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140966

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The long period of ³He-rich solar energetic particles measured by Solar Orbiter 2020 November 17–23

R. Bučík, G. M. Mason, R. Gómez-Herrero, D. Lario, L. Balmaceda, N. V. Nitta, V. Krupař, N. Dresing, G. C. Ho, R. C. Allen et al. (24 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202141009

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Solar energetic particle heavy ion properties in the widespread event of 2020 November 29

G. M. Mason, C. M. S. Cohen, G. C. Ho, D. G. Mitchell, R. C. Allen, M. E. Hill, G. B. Andrews, L. Berger, S. Boden, S. Böttcher et al. (50 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202141310

Open Access

Capturing transient plasma flows and jets in the solar corona

L. P. Chitta, S. K. Solanki, H. Peter, R. Aznar Cuadrado, L. Teriaca, U. Schühle, F. Auchère, D. Berghmans, E. Kraaikamp, S. Gissot and C. Verbeeck

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202141683

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The first coronal mass ejection observed in both visible-light and UV H I Ly-α channels of the Metis coronagraph on board Solar Orbiter

V. Andretta, A. Bemporad, Y. De Leo, G. Jerse, F. Landini, M. Mierla, G. Naletto, M. Romoli, C. Sasso, A. Slemer et al. (61 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202142407

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Propagating brightenings in small loop-like structures in the quiet-Sun corona: Observations from Solar Orbiter/EUI

Sudip Mandal, Hardi Peter, Lakshmi Pradeep Chitta, Sami K. Solanki, Regina Aznar Cuadrado, Luca Teriaca, Udo Schühle, David Berghmans and Frédéric Auchère

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202142041

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Radial evolution of the April 2020 stealth coronal mass ejection between 0.8 and 1 AU - Comparison of Forbush decreases at Solar Orbiter and near the Earth

Johan L. Freiherr von Forstner, Mateja Dumbović, Christian Möstl, Jingnan Guo, Athanasios Papaioannou, Robert Elftmann, Zigong Xu, Jan Christoph Terasa, Alexander Kollhoff, Robert F. Wimmer-Schweingruber et al. (33 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202039848

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In situ multi-spacecraft and remote imaging observations of the first CME detected by Solar Orbiter and BepiColombo

E. E. Davies, C. Möstl, M. J. Owens, A. J. Weiss, T. Amerstorfer, J. Hinterreiter, M. Bauer, R. L. Bailey, M. A. Reiss, R. J. Forsyth et al. (13 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202040113

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Turbulence and wave transmission at an ICME-driven shock observed by the Solar Orbiter and Wind

L.-L. Zhao, G. P. Zank, J. S. He, D. Telloni, Q. Hu, G. Li, M. Nakanotani, L. Adhikari, E. K. J. Kilpua, T. S. Horbury et al. (3 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140450

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STIX X-ray microflare observations during the Solar Orbiter commissioning phase

Andrea Francesco Battaglia, Jonas Saqri, Paolo Massa, Emma Perracchione, Ewan C. M. Dickson, Hualin Xiao, Astrid M. Veronig, Alexander Warmuth, Marina Battaglia, Gordon J. Hurford et al. (27 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140524

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Study of two interacting interplanetary coronal mass ejections encountered by Solar Orbiter during its first perihelion passage - Observations and modeling

D. Telloni, C. Scolini, C. Möstl, G. P. Zank, L.-L. Zhao, A. J. Weiss, M. A. Reiss, R. Laker, D. Perrone, Y. Khotyaintsev et al. (39 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140648

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Evolution of anisotropic turbulence in the fast and slow solar wind: Theory and Solar Orbiter measurements

L. Adhikari, G. P. Zank, L.-L. Zhao, D. Telloni, T. S. Horbury, H. O’Brien, V. Evans, V. Angelini, C. J. Owen, P. Louarn and A. Fedorov

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140672

Press Release

Open Access

Energetic ions in the Venusian system: Insights from the first Solar Orbiter flyby

R. C. Allen, I. Cernuda, D. Pacheco, L. Berger, Z. G. Xu, J. L. Freiherr von Forstner, J. Rodríguez-Pacheco, R. F. Wimmer-Schweingruber, G. C. Ho, G. M. Mason et al. (47 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140803

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Multi-spacecraft observations of the structure of the sheath of an interplanetary coronal mass ejection and related energetic ion enhancement

E. K. J. Kilpua, S. W. Good, N. Dresing, R. Vainio, E. E. Davies, R. J. Forsyth, J. Gieseler, B. Lavraud, E. Asvestari, D. E. Morosan et al. (11 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140838

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Solar wind current sheets and deHoffmann-Teller analysis - First results from Solar Orbiter’s DC electric field measurements

K. Steinvall, Yu. V. Khotyaintsev, G. Cozzani, A. Vaivads, E. Yordanova, A. I. Eriksson, N. J. T. Edberg, M. Maksimovic, S. D. Bale, T. Chust et al. (18 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140855

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Deriving the bulk properties of solar wind electrons observed by Solar Orbiter - A preliminary study of electron plasma thermodynamics

G. Nicolaou, R. T. Wicks, C. J. Owen, D. O. Kataria, A. Chandrasekhar, G. R. Lewis, D. Verscharen, V. Fortunato, G. Mele, R. DeMarco and R. Bruno

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140875

Open Access

Solar Orbiter’s first Venus flyby - MAG observations of structures and waves associated with the induced Venusian magnetosphere

M. Volwerk, T. S. Horbury, L. D. Woodham, S. D. Bale, C. Simon Wedlund, D. Schmid, R. C. Allen, V. Angelini, W. Baumjohann, L. Berger et al. (11 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140910

Open Access

Solar Orbiter observations of the Kelvin-Helmholtz waves in the solar wind

R. Kieokaew, B. Lavraud, Y. Yang, W. H. Matthaeus, D. Ruffolo, J. E. Stawarz, S. Aizawa, C. Foullon, V. Génot, R. F. Pinto et al. (10 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140915

Open Access

Multi-point analysis of coronal mass ejection flux ropes using combined data from Solar Orbiter, BepiColombo, and Wind

A. J. Weiss, C. Möstl, E. E. Davies, T. Amerstorfer, M. Bauer, J. Hinterreiter, M. A. Reiss, R. L. Bailey, T. S. Horbury, H. O’Brien et al. (8 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140919

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First-year ion-acoustic wave observations in the solar wind by the RPW/TDS instrument on board Solar Orbiter

D. Píša, J. Souček, O. Santolík, M. Hanzelka, G. Nicolaou, M. Maksimovic, S. D. Bale, T. Chust, Y. Khotyaintsev, V. Krasnoselskikh et al. (14 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140928

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Cosmic-ray flux predictions and observations for and with Metis on board Solar Orbiter

C. Grimani, V. Andretta, P. Chioetto, V. Da Deppo, M. Fabi, S. Gissot, G. Naletto, A. Persici, C. Plainaki, M. Romoli et al. (34 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140930

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Statistical study of electron density turbulence and ion-cyclotron waves in the inner heliosphere: Solar Orbiter observations

F. Carbone, L. Sorriso-Valvo, Yu. V. Khotyaintsev, K. Steinvall, A. Vecchio, D. Telloni, E. Yordanova, D. B. Graham, N. J. T. Edberg, A. I. Eriksson et al. (20 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140931

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Observations of whistler mode waves by Solar Orbiter’s RPW Low Frequency Receiver (LFR): In-flight performance and first results

T. Chust, M. Kretzschmar, D. B. Graham, O. Le Contel, A. Retinò, A. Alexandrova, M. Berthomier, L. Z. Hadid, F. Sahraoui, A. Jeandet et al. (22 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140932

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Solar Orbiter’s first Venus flyby: Observations from the Radio and Plasma Wave instrument

L. Z. Hadid, N. J. T. Edberg, T. Chust, D. Píša, A. P. Dimmock, M. W. Morooka, M. Maksimovic, Yu. V. Khotyaintsev, J. Souček, M. Kretzschmar et al. (34 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140934

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Density fluctuations associated with turbulence and waves - First observations by Solar Orbiter

Yu. V. Khotyaintsev, D. B. Graham, A. Vaivads, K. Steinvall, N. J. T. Edberg, A. I. Eriksson, E. P. G. Johansson, L. Sorriso-Valvo, M. Maksimovic, S. D. Bale et al. (14 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140936

Open Access

The first widespread solar energetic particle event observed by Solar Orbiter on 2020 November 29

A. Kollhoff, A. Kouloumvakos, D. Lario, N. Dresing, R. Gómez-Herrero, L. Rodríguez-García, O. E. Malandraki, I. G. Richardson, A. Posner, K.-L. Klein et al. (59 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140937

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First Solar Orbiter observation of the Alfvénic slow wind and identification of its solar source

R. D’Amicis, R. Bruno, O. Panasenco, D. Telloni, D. Perrone, M. F. Marcucci, L. Woodham, M. Velli, R. De Marco, V. Jagarlamudi et al. (20 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140938

Open Access

First year of energetic particle measurements in the inner heliosphere with Solar Orbiter’s Energetic Particle Detector

R. F. Wimmer-Schweingruber, N. P. Janitzek, D. Pacheco, I. Cernuda, F. Espinosa Lara, R. Gómez-Herrero, G. M. Mason, R. C. Allen, Z. G. Xu, F. Carcaboso et al. (38 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140940

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Kinetic electrostatic waves and their association with current structures in the solar wind

D. B. Graham, Yu. V. Khotyaintsev, A. Vaivads, N. J. T. Edberg, A. I. Eriksson, E. P. G. Johansson, L. Sorriso-Valvo, M. Maksimovic, J. Souček, D. Píša et al. (14 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140943

Open Access

Whistler waves observed by Solar Orbiter/RPW between 0.5 AU and 1 AU

M. Kretzschmar, T. Chust, V. Krasnoselskikh, D. Graham, L. Colomban, M. Maksimovic, Yu. V. Khotyaintsev, J. Soucek, K. Steinvall, O. Santolík et al. (22 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140945

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Imaging from STIX visibility amplitudes

Paolo Massa, Emma Perracchione, Sara Garbarino, Andrea F. Battaglia, Federico Benvenuto, Michele Piana, Gordon Hurford and Säm Krucker

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140946

Open Access

Solar Orbiter Radio and Plasma Waves – Time Domain Sampler: In-flight performance and first results

J. Soucek, D. Píša, I. Kolmasova, L. Uhlir, R. Lan, O. Santolík, V. Krupar, O. Kruparova, J. Baše, M. Maksimovic et al. (13 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140948

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Solar Orbiter observations of an ion-scale flux rope confined to a bifurcated solar wind current sheet

J. P. Eastwood, J. E. Stawarz, T. D. Phan, R. Laker, S. Robertson, L.-L. Zhao, G. P. Zank, B. Lavraud, M. A. Shay, V. Evans et al. (3 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140949

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The angular-momentum flux in the solar wind observed during Solar Orbiter’s first orbit

Daniel Verscharen, David Stansby, Adam J. Finley, Christopher J. Owen, Timothy Horbury, Milan Maksimovic, Marco Velli, Stuart D. Bale, Philippe Louarn, Andrei Fedorov et al. (13 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140956

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PSP/IS⊙IS observations of the 29 November 2020 solar energetic particle event

C. M. S. Cohen, E. R. Christian, A. C. Cummings, A. J. Davis, M. I. Desai, G. A. de Nolfo, J. Giacalone, M. E. Hill, C. J. Joyce, A. W. Labrador et al. (17 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140967

Open Access

First dust measurements with the Solar Orbiter Radio and Plasma Wave instrument

A. Zaslavsky, I. Mann, J. Soucek, A. Czechowski, D. Píša, J. Vaverka, N. Meyer-Vernet, M. Maksimovic, E. Lorfèvre, K. Issautier et al. (13 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140969

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Whistler instability driven by the sunward electron deficit in the solar wind - High-cadence Solar Orbiter observations

L. Berčič, D. Verscharen, C. J. Owen, L. Colomban, M. Kretzschmar, T. Chust, M. Maksimovic, D. O. Kataria, C. Anekallu, E. Behar et al. (12 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140970

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First light observations of the solar wind in the outer corona with the Metis coronagraph

M. Romoli, E. Antonucci, V. Andretta, G. E. Capuano, V. Da Deppo, Y. De Leo, C. Downs, S. Fineschi, P. Heinzel, F. Landini et al. (58 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140980

Open Access

Solar Orbiter/RPW antenna calibration in the radio domain and its application to type III burst observations

A. Vecchio, M. Maksimovic, V. Krupar, X. Bonnin, A. Zaslavsky, P. L. Astier, M. Dekkali, B. Cecconi, S. D. Bale, T. Chust et al. (11 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140988

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Simulations of radio-wave anisotropic scattering to interpret type III radio burst data from Solar Orbiter, Parker Solar Probe, STEREO, and Wind

S. Musset, M. Maksimovic, E. Kontar, V. Krupar, N. Chrysaphi, X. Bonnin, A. Vecchio, B. Cecconi, A. Zaslavsky, K. Issautier et al. (2 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202140998

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Stereoscopy of extreme UV quiet Sun brightenings observed by Solar Orbiter/EUI

A. N. Zhukov, M. Mierla, F. Auchère, S. Gissot, L. Rodriguez, E. Soubrié, W. T. Thompson, B. Inhester, B. Nicula, P. Antolin et al. (20 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202141010

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Multiscale views of an Alfvénic slow solar wind: 3D velocity distribution functions observed by the Proton-Alpha Sensor of Solar Orbiter

P. Louarn, A. Fedorov, L. Prech, C. J. Owen, R. Bruno, S. Livi, B. Lavraud, A. P. Rouillard, V. Génot, N. André et al. (22 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202141095

Open Access

Magnetic reconnection as a mechanism to produce multiple thermal proton populations and beams locally in the solar wind

B. Lavraud, R. Kieokaew, N. Fargette, P. Louarn, A. Fedorov, N. André, G. Fruit, V. Génot, V. Réville, A. P. Rouillard et al. (30 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202141149

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First observations from the SPICE EUV spectrometer on Solar Orbiter

A. Fludra, M. Caldwell, A. Giunta, T. Grundy, S. Guest, S. Leeks, S. Sidher, F. Auchère, M. Carlsson, D. Hassler et al. (21 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202141221

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Solar Orbiter’s encounter with the tail of comet C/2019 Y4 (ATLAS): Magnetic field draping and cometary pick-up ion waves

L. Matteini, R. Laker, T. Horbury, L. Woodham, S. D. Bale, J. E. Stawarz, T. Woolley, K. Steinvall, G. H. Jones, S. R. Grant et al. (29 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202141229

Open Access

Switchback-like structures observed by Solar Orbiter

A. Fedorov, P. Louarn, C. J. Owen, T. S. Horbury, L. Prech, T. Durovcova, A. Barthe, A. P. Rouillard, J. C. Kasper, S. D. Bale et al. (12 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202141246

Open Access

First observations and performance of the RPW instrument on board the Solar Orbiter mission

M. Maksimovic, J. Souček, T. Chust, Y. Khotyaintsev, M. Kretzschmar, X. Bonnin, A. Vecchio, O. Alexandrova, S. D. Bale, D. Bérard et al. (100 more)

Published online: 14 December 2021

DOI: https://doi.org/10.1051/0004-6361/202141271

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Multi-instrument STIX microflare study

Jonas Saqri, Astrid M. Veronig, Alexander Warmuth, Ewan C. M. Dickson, Andrea Francesco Battaglia, Tatiana Podladchikova, Hualin Xiao, Marina Battaglia, Gordon J. Hurford and Säm Krucker

Published online: 04 March 2022

DOI: https://doi.org/10.1051/0004-6361/202142373

Open Access

Analysis of multiscale structures at the quasi-perpendicular Venus bow shock - Results from Solar Orbiter’s first Venus flyby

A. P. Dimmock, Yu. V. Khotyaintsev, A. Lalti, E. Yordanova, N. J. T. Edberg, K. Steinvall, D. B. Graham, L. Z. Hadid, R. C. Allen, A. Vaivads et al. (16 more)

Published online: 13 April 2022

DOI: https://doi.org/10.1051/0004-6361/202140954

Astronomy & Astrophysics

Solar Orbiter First Results (Cruise Phase)