Search Publications
A new weak-field magnetic DA white dwarf in the local 20 pc volume. The frequency of magnetic fields in DA stars
Bagnulo, S.; Landstreet, J. D.
We report the discovery of a new magnetic DA white dwarf (WD), WD 0011 - 721, which is located within the very important 20 pc volume-limited sample of the closest WDs to the Sun. This star has a mean field modulus ⟨|B|⟩ of 343 kG, and from the polarisation signal we deduce a line-of-sight field component of 75 kG. The magnetic field is sufficient…
Characterising the surface magnetic fields of T Tauri stars with high-resolution near-infrared spectroscopy
Hussain, G. A. J.; Kochukhov, O.; Lavail, A.
Aims: In this paper, we aim to characterise the surface magnetic fields of a sample of eight T Tauri stars from high-resolution near-infrared spectroscopy. Some stars in our sample are known to be magnetic from previous spectroscopic or spectropolarimetric studies. Our goals are firstly to apply Zeeman broadening modelling to T Tauri stars wi…
Globular cluster candidates in the Galactic bulge: Gaia and VVV view of the latest discoveries
Minniti, D.; Rejkuba, M.; Zoccali, M. +7 more
Context. Thanks to the recent wide-area photometric surveys, the number of star cluster candidates have risen exponentially in the last few years. Most detections, however, are based only on the presence of an overdensity of stars in a given region or an overdensity of variable stars, regardless of their distance. As candidates, their detection ha…
Spatial distribution of stellar mass and star formation activity at 0.2 < z < 1.2 across and along the main sequence
Popesso, P.; Oesch, P. A.; Illingworth, G. D. +5 more
High-resolution multi-wavelength photometry is crucial to explore the spatial distribution of star formation in galaxies and understand how these evolve. To this aim, in this paper we exploit the deep, multi-wavelength Hubble Space Telescope (HST) data available in the central parts of the Great Observatories Origins Deep Survey (GOODS) fields and…
Extreme starlight polarization in a region with highly polarized dust emission
Tassis, Konstantinos; Hensley, Brandon S.; Blinov, Dmitry +2 more
Context. Galactic dust emission is polarized at unexpectedly high levels, as revealed by Planck.
Aims: The origin of the observed ≃20% polarization fractions can be identified by characterizing the properties of optical starlight polarization in a region with maximally polarized dust emission.
Methods: We measure the R-band linear polari…
Mass discrepancy analysis for a select sample of Type II-Plateau supernovae
Bersten, Melina C.; Martinez, Laureano
The detailed study of supernovae (SNe) and their progenitors allows a better understanding of the evolution of massive stars and how these end their lives. Despite its importance, the range of physical parameters for the most common type of explosion, the type II supernovae (SNe II), is still unknown. In particular, previous studies of type II-Pla…
Photoionized emission and absorption features in the high-resolution X-ray spectra of NGC 3783
Kaastra, J. S.; Kriss, G. A.; Arav, N. +14 more
Our Swift monitoring program triggered two joint XMM-Newton, NuSTAR, and HST observations on 11 and 21 December 2016 targeting NGC 3783 because its soft X-ray continuum was heavily obscured. Consequently, emission features, including the O VII radiative recombination continuum, stand out above the diminished continuum. We focus on the photoionized…
16O/18O ratio in water in the coma of comet 67P/Churyumov-Gerasimenko measured with the Rosetta/ROSINA double-focusing mass spectrometer
De Keyser, Johan; Gombosi, Tamas I.; Berthelier, Jean-Jacques +11 more
The European Space Agency spacecraft Rosetta accompanied the Jupiter-family comet 67P/Churyumov-Gerasimenko for over 2 yr along its trajectory through the inner solar system. Between 2014 and 2016, it performed almost continuous in situ measurements of the comet's gaseous atmosphere in close proximity to its nucleus. In this study, the 16
Ruprecht 147 DANCe. I. Members, empirical isochrone, luminosity, and mass distributions
Tamura, M.; Bertin, E.; Miret-Roig, N. +10 more
Context. Ruprecht 147 is the oldest (2.5 Gyr) open cluster in the solar vicinity (< 300 pc), making it an important target for stellar evolution studies and exoplanet searches.
Aims: We aim to derive a census of members and the luminosity, mass, and spatial distributions of the cluster.
Methods: We used an astro-photometric data set i…
Variable emission mechanism of a Type IV radio burst
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…