Search Publications
Hubble spectroscopy of LB-1: Comparison with B+black-hole and Be+stripped-star models
Smartt, S. J.; Dufton, P. L.; Lennon, D. J. +10 more
Context. LB-1 (alias ALS 8775) has been proposed as either an X-ray dim B-type star plus black hole (B+BH) binary or a Be star plus an inflated stripped star (Be+Bstr) binary. The latter hypothesis contingent upon the detection and characterization of the hidden broad-lined star in a composite optical spectrum.
Aims: Our study is aimed at tes…
Fragmentation and kinematics in high-mass star formation. CORE-extension targeting two very young high-mass star-forming regions
Henning, Th.; Beuther, H.; Klaassen, P. +24 more
Context. The formation of high-mass star-forming regions from their parental gas cloud and the subsequent fragmentation processes lie at the heart of star formation research.
Aims: We aim to study the dynamical and fragmentation properties at very early evolutionary stages of high-mass star formation.
Methods: Employing the NOrthern Exte…
Solar energetic particle heavy ion properties in the widespread event of 2020 November 29
Kulkarni, S. R.; Mitchell, D. G.; McComas, D. J. +57 more
Context. Following a multi-year minimum of solar activity, a solar energetic particle event on 2020 Nov. 29 was observed by multiple spacecraft covering a wide range of solar longitudes including ACE, the Solar Terrestrial Relations Observatory-A, and the recently launched Parker Solar Probe and Solar Orbiter.
Aims: Multi-point observations o…
Weighing the Galactic disk in sub-regions of the solar neighbourhood using Gaia DR2
Monari, G.; de Salas, P. F.; Widmark, A.
Aims: We infer the gravitational potential of the Galactic disk by analysing the phase-space densities of 120 stellar samples in 40 spatially separate sub-regions of the solar neighbourhood, using Gaia's second data release (DR2), in order to quantify spatially dependent systematic effects that bias this type of measurement.
Methods: The…
Variable stars in the VVV globular clusters. II. NGC 6441, NGC 6569, NGC 6626 (M 28), NGC 6656 (M 22), 2MASS-GC 02, and Terzan 10
Carballo-Bello, Julio A.; Smith, Leigh C.; Minniti, Dante +18 more
Context. The Galactic globular clusters (GGCs) located in the inner regions of the Milky Way suffer from high extinction that makes their observation challenging. High densities of field stars in their surroundings complicate their study even more. The VISTA Variables in the Via Lactea (VVV) survey provides a way to explore these GGCs in the near-…
Gas compression and stellar feedback in the tidally interacting and ram-pressure stripped Virgo spiral galaxy NGC 4654
Braine, J.; Vollmer, B.; Lizée, T. +1 more
Due to an environment that promotes gravitational interactions and ram pressure stripping, galaxies within clusters are particularly likely to present unusual interstellar medium (ISM) properties. NGC 4654 is a Virgo cluster galaxy seen almost face-on, which undergoes nearly edge-on gas ram pressure stripping and a fly-by gravitational interaction…
First observations from the SPICE EUV spectrometer on Solar Orbiter
Williams, D.; Peter, H.; Chitta, L. P. +28 more
Aims: We present first science observations taken during the commissioning activities of the Spectral Imaging of the Coronal Environment (SPICE) instrument on the ESA/NASA Solar Orbiter mission. SPICE is a high-resolution imaging spectrometer operating at extreme ultraviolet (EUV) wavelengths. In this paper we illustrate the possible types of…
Testing abundance-age relations beyond solar analogues with Kepler LEGACY stars
Miglio, Andrea; Montalbán, Josefina; Morel, Thierry +2 more
The prospects of using abundance ratios as stellar age indicators appear promising for solar analogues, but the usefulness of this technique for stars spanning a much wider parameter space remains to be established. We present abundances of 21 elements in a sample of 13 bright FG dwarfs drawn from the Kepler LEGACY sample to examine the applicabil…
Three microlensing planets with no caustic-crossing features
Han, Cheongho; Udalski, Andrzej; Lee, Chung-Uk +31 more
Aims: We search for microlensing planets with signals exhibiting no caustic-crossing features, considering the possibility that such signals may be missed due to their weak and featureless nature.
Methods: For this purpose, we reexamine the lensing events found by the KMTNet survey before the 2019 season. From this investigation, we find…
TESS unveils the optical phase curve of KELT-1b. Thermal emission and ellipsoidal variation from the brown dwarf companion along with the stellar activity
Mallonn, M.; Agol, E.; von Essen, C. +8 more
We present the detection and analysis of the phase curve of KELT-1b at optical wavelengths, analyzing data taken by the Transiting Exoplanet Survey Satellite (TESS) during cycle 2 and sector 17. With a mass of ~27 MJup, KELT-1b is an example of a low-mass brown dwarf. Due to the high mass and close proximity of its companion, the host s…