Search Publications
Determining the source and eruption dynamics of a stealth CME using NLFFF modelling and MHD simulations
Yardley, S. L.; Pagano, P.; Mackay, D. H. +1 more
Context. Coronal mass ejections (CMEs) that exhibit weak or no eruption signatures in the low corona, known as stealth CMEs, are problematic as upon arrival at Earth they can lead to geomagnetic disturbances that were not predicted by space weather forecasters.
Aims: We investigate the origin and eruption of a stealth event that occurred on 2…
The variable absorption in the X-ray spectrum of GRB 190114C
Perna, Rosalba; Campana, Sergio; Lazzati, Davide +2 more
Gamma-ray burst (GRB) 190114C was a bright burst that occurred in the local Universe (z = 0.425). It was the first GRB ever detected at teraelectronvolt (TeV) energies, and this was thanks to MAGIC. We characterize the ambient medium properties of the host galaxy through the study of the absorbing X-ray column density. Using a combination of Swift…
Towards a fully consistent Milky Way disk model. IV. The impact of Gaia DR2 and APOGEE
Just, A.; Sysoliatina, K.
Aims: We present an updated version of the semi-analytic Just-Jahrei (JJ) model of the Galactic disk and constrain its parameters in the Solar neighbourhood.
Methods: The new features of the JJ model include a simple two-component gaseous disk, a star-formation rate (SFR) function of the thick disk that has been extended in time, and a c…
Description of turbulent dynamics in the interstellar medium: multifractal-microcanonical analysis. I. Application to Herschel observations of the Musca filament
Schneider, N.; Bontemps, S.; Elia, D. +10 more
Observations of the interstellar medium (ISM) show a complex density and velocity structure, which is in part attributed to turbulence. Consequently, the multifractal formalism should be applied to observation maps of the ISM in order to characterize its turbulent and multiplicative cascade properties. However, the multifractal formalism, even in …
Four Jovian planets around low-luminosity giant stars observed by the EXPRESS and PPPS
Jones, M. I.; Trifonov, T.; Soto, M. G. +14 more
We report the discovery of planetary companions orbiting four low-luminosity giant stars with M⋆ between 1.04 and 1.39 M⊙. All four host stars have been independently observed by the EXoPlanets aRound Evolved StarS (EXPRESS) program and the Pan-Pacific Planet Search (PPPS). The companion signals were revealed by multi-epoch p…
The impact of massive stars and black holes on the fate of open star clusters and their tidal streams
Wang, Long; Jerabkova, Tereza
Context. We use present-day observations to investigate how the content of massive OB stars affects the long-term evolution of young open clusters and their tidal streams, and how such an effect influences the constraint of initial conditions.
Aims: OB stars are typically found in binaries. They have a strong wind mass loss during the first f…
UVES analysis of red giants in the bulge globular cluster NGC 6522
Chiappini, C.; Bica, E.; Barbuy, B. +10 more
Context. NGC 6522 is a moderately metal-poor bulge globular cluster ([Fe/H] ~ −1.0), and it is a well-studied representative among a number of moderately metal-poor blue horizontal branch clusters located in the bulge. The NGC 6522 abundance pattern can give hints on the earliest chemical enrichment in the central Galaxy.
Aims: The aim of thi…
S stars and s-process in the Gaia era. II. Constraining the luminosity of the third dredge-up with Tc-rich S stars
Van Winckel, Hans; Wallerstein, George; Plez, Bertrand +6 more
Context. S stars are late-type giants that are transition objects between M-type stars and carbon stars on the asymptotic giant branch (AGB). They are classified into two types: intrinsic or extrinsic, based on the presence or absence of technetium (Tc). The Tc-rich or intrinsic S stars are thermally pulsing (TP-)AGB stars internally producing s-p…
Plasma densities, flow, and solar EUV flux at comet 67P. A cross-calibration approach
Nilsson, H.; Henri, P.; Edberg, N. J. T. +7 more
Context. During its two-year mission at comet 67P, Rosetta nearly continuously monitored the inner coma plasma environment for gas production rates varying over three orders of magnitude, at distances to the nucleus ranging from a few to a few hundred kilometres. To achieve the best possible measurements, cross-calibration of the plasma instrument…
Testing the models of X-ray driven photoevaporation with accreting stars in the Orion Nebula Cluster
Manara, C. F.; Preibisch, T.; Ercolano, B. +1 more
Context. Recent works highlight the importance of stellar X-rays on the evolution of the circumstellar disks of young stellar objects, especially for disk photoevaporation.
Aims: A signature of this process may be seen in the so far tentatively observed dependence of stellar accretion rates on X-ray luminosities. According to models of X-ray …