Search Publications

Hubble Space Telescope imaging of the extremely metal-poor globular cluster EXT8 in Messier 31
DOI: 10.1051/0004-6361/202141046 Bibcode: 2021A&A...651A.102L

Romanowsky, Aaron J.; Brodie, Jean P.; Larsen, Søren S.

We recently found the globular cluster (GC) EXT8 in M 31 to have an extremely low metallicity of [Fe/H] = −2.91 ± 0.04 using high-resolution spectroscopy. Here we present a colour-magnitude diagram (CMD) for EXT8, obtained with the Wide Field Camera 3 on board the Hubble Space Telescope. Compared with the CMDs of metal-poor Galactic GCs, we find t…

2021 Astronomy and Astrophysics
eHST 10
Energetic particle evolution during coronal mass ejection passage from 0.3 to 1 AU
DOI: 10.1051/0004-6361/202039933 Bibcode: 2021A&A...651A...2J

Mitchell, D. G.; McComas, D. J.; Bale, S. D. +21 more

We provide analysis of a coronal mass ejection (CME) that passed over Parker Solar Probe (PSP) on January 20, 2020 when the spacecraft was at just 0.32 AU. The Integrated Science Investigation of the Sun instrument suite measures energetic particle populations associated with the CME before, during, and after its passage over the spacecraft. We ob…

2021 Astronomy and Astrophysics
SOHO 10
Deriving the bulk properties of solar wind electrons observed by Solar Orbiter. A preliminary study of electron plasma thermodynamics
DOI: 10.1051/0004-6361/202140875 Bibcode: 2021A&A...656A..10N

Lewis, G. R.; Kataria, D. O.; Owen, C. J. +8 more

Context. We demonstrate the calculation of solar wind electron bulk parameters based on recent observations by Solar Wind Analyser - Electron Analyser System on board Solar Orbiter. We use our methods to derive the electron bulk parameters in a time interval spanning several hours. We attempt a preliminary examination of the polytropic behavior of…

2021 Astronomy and Astrophysics
SolarOrbiter 10
2019 International Women's Day event. Two-step solar flare with multiple eruptive signatures and low Earth impact
DOI: 10.1051/0004-6361/202140752 Bibcode: 2021A&A...652A.159D

Magdalenić, J.; Temmer, M.; Veronig, A. M. +7 more

Context. We present a detailed analysis of an eruptive event that occurred on 2019 March 8 in the active region AR 12734, which we refer as the International Women's Day event. The event under study is intriguing based on several aspects: (1) low-coronal eruptive signatures come in `pairs', namely, there is a double-peaked flare, two coronal dimmi…

2021 Astronomy and Astrophysics
SOHO 10
The Cosmic Large-Scale Structure in X-rays (CLASSIX) Cluster Survey. III. The Perseus-Pisces supercluster and the Southern Great Wall as traced by X-ray luminous galaxy clusters
DOI: 10.1051/0004-6361/202140864 Bibcode: 2021A&A...651A..16B

Böhringer, Hans; Chon, Gayoung; Trümper, Joachim

The Perseus-Pisces supercluster is known as one of the largest structures in the nearby Universe that has been charted by the galaxy and galaxy cluster distributions. For the latter mostly clusters from the Abell catalogue have been used. Here we take a new approach to a quantitative characterisation of the Perseus-Pisces supercluster using a stat…

2021 Astronomy and Astrophysics
XMM-Newton 10
White dwarf-open cluster associations based on Gaia DR2
DOI: 10.1051/0004-6361/202039276 Bibcode: 2021A&A...645A..13P

Paunzen, E.; Prišegen, M.; Piecka, M. +2 more

Context. Fundamental parameters and physical processes leading to the formation of white dwarfs (WDs) may be constrained and refined by discovering WDs in open clusters (OCs). Cluster membership can be utilized to establish the precise distances, luminosities, ages, and progenitor masses of such WDs.
Aims: We compile a list of probable WDs th…

2021 Astronomy and Astrophysics
Gaia 10
Multi-spacecraft study of the solar wind at solar minimum: Dependence on latitude and transient outflows
DOI: 10.1051/0004-6361/202140679 Bibcode: 2021A&A...652A.105L

Fedorov, A.; Eastwood, J. P.; Owens, M. J. +15 more

Context. The recent launches of Parker Solar Probe, Solar Orbiter (SO), and BepiColombo, along with several older spacecraft, have provided the opportunity to study the solar wind at multiple latitudes and distances from the Sun simultaneously.
Aims: We take advantage of this unique spacecraft constellation, along with low solar activity acro…

2021 Astronomy and Astrophysics
SolarOrbiter 10
Online data analysis system of the INTEGRAL telescope
DOI: 10.1051/0004-6361/202037850 Bibcode: 2021A&A...651A..97N

Paltani, S.; Tramacere, A.; Ferrigno, C. +3 more

Context. During more than 17 years of operation in space, the INTErnational Gamma-Ray Astrophysics Laboratory (INTEGRAL) telescope has accumulated a large data set that contains records of hard X-ray and soft γ-ray astronomical sources. These data can be reused in the context of multi-wavelength or multi-messenger studies of astronomical sources a…

2021 Astronomy and Astrophysics
INTEGRAL 10
Solar Orbiter Radio and Plasma Waves - Time Domain Sampler: In-flight performance and first results
DOI: 10.1051/0004-6361/202140948 Bibcode: 2021A&A...656A..26S

Maksimovic, M.; Bale, S. D.; Chust, T. +20 more

Context. The Radio and Plasma Waves (RPW) instrument on board Solar Orbiter has been operating nearly continuously since the launch in February 2020. The Time Domain Sampler (TDS) receiver of the RPW instrument is dedicated to waveform measurements of plasma waves and dust impact signatures in an intermediate frequency range from 0.2 to 200 kHz. <…

2021 Astronomy and Astrophysics
SolarOrbiter 10
Low star formation efficiency due to turbulent adiabatic compression in the Taffy bridge
DOI: 10.1051/0004-6361/202037887 Bibcode: 2021A&A...647A.138V

Braine, J.; Schneider, B.; Vollmer, B. +1 more

The Taffy system (UGC 12914/15) consists of two massive spiral galaxies that had a head-on collision about 20 Myr ago. It represents an ideal laboratory for studying the reaction of the interstellar medium (ISM) to a high-speed (∼1000 km s−1) gas-gas collision. New sensitive, high-resolution (2.7″ or ∼800 pc) CO(1−0) observations of the…

2021 Astronomy and Astrophysics
eHST 10