Search Publications
Observations of Asymmetric Lobe Convection for Weak and Strong Tail Activity
Østgaard, N.; Tenfjord, P.; Reistad, J. P. +6 more
In this study we use high-quality convection data from the Electron Drift Instrument on board Cluster to investigate how near-Earth tail activity affects the average convection pattern in the magnetotail lobes when the interplanetary magnetic field has a dominating east-west (By) component. Two different proxies have been used to repres…
Discovery of a giant and luminous Lyα+C IV+He II nebula at z = 3.326 with extreme emission line ratios
Pérez-Fournon, I.; Ivison, R. J.; Omont, A. +17 more
We present the discovery of HLock01-LAB, a luminous and large Lyα nebula at z = 3.326. Medium-band imaging and long-slit spectroscopic observations with the Gran Telescopio Canarias reveal extended emission in the Lyα 1215 Å, C IV 1550 Å, and He II 1640 Å lines over ∼100 kpc, and a total luminosity LLyα = (6.4 ± 0.1)×1044 erg…
The extreme O-type spectroscopic binary HD 93129A. A quantitative, multiwavelength analysis
Gruner, D.; Hamann, W. -R.; Oskinova, L. M. +6 more
Context. HD 93129A was classified as the earliest O-type star in the Galaxy (O2 If*) and is considered as the prototype of its spectral class. However, interferometry shows that this object is a binary system, while recent observations even suggest a triple configuration. None of the previous spectral analyses of this object accounted for its mult…
Multiple Stellar Populations of Globular Clusters from Homogeneous Ca-CN-CH Photometry. V. {{cn}}_{JWL}}^{{\prime} } as a Surrogate cn JWL Index and NGC 6723
Lee, Jae-Woo
We introduce new color indices {{cn}}JWL}{\prime } (=Ca CTIO - Ca JWL) and ch JWL [=(JWL43 - b) - (b - y)], accurate photometric measures of the CN band at λ3883 and the CH G band, respectively, in the study of the multiple populations (MPs) in globular clusters (GCs). Our photometric CN-CH re…
Validation of the IPSL Venus GCM Thermal Structure with Venus Express Data
Piccioni, Giuseppe; Tellmann, Silvia; Lebonnois, Sebastien +4 more
General circulation models (GCMs) are valuable instruments to understand the most peculiar features in the atmospheres of planets and the mechanisms behind their dynamics. Venus makes no exception and it has been extensively studied thanks to GCMs. Here we validate the current version of the Institut Pierre Simon Laplace (IPSL) Venus GCM, by means…
Transit analysis of the CoRoT-5, CoRoT-8, CoRoT-12, CoRoT-18, CoRoT-20, and CoRoT-27 systems with combined ground- and space-based photometry
Heras, A. M.; Casanova, V.; Fernández, M. +2 more
We have initiated a dedicated project to follow-up with ground-based photometry the transiting planets discovered by CoRoT in order to refine the orbital elements, constrain their physical parameters, and search for additional bodies in the system. From 2012 September to 2016 December we carried out 16 transit observations of six CoRoT planets (Co…
The true nature of Swift J0746.3-1608: a possible Intermediate Polar showing accretion state changes
Mukai, K.; de Martino, D.; Bernardini, F. +1 more
Optical and X-ray observations suggested that the 9.38 h binary, SWIFT J0746.3-1608 could be a cataclysmic variable (CV) of the magnetic or nova-like type, or a low-mass X-ray binary. Its optical, UV, and X-ray light curves are strongly variable over years. We report on a recent XMM-Newton observation (2018 April 28), when the source had recovered…
First resolved observations of a highly asymmetric debris disc around HD 160305 with VLT/SPHERE
Boccaletti, Anthony; Ménard, François; Kral, Quentin +36 more
Context. Direct imaging of debris discs gives important information about their nature, their global morphology, and allows us to identify specific structures possibly in connection with the presence of gravitational perturbers. It is the most straightforward technique to observe planetary systems as a whole.
Aims: We present the first resolv…
Elemental Abundance Distributions in the (R, V ϕ ) Plane with LAMOST DR5 and Gaia DR2
Zhao, Gang; Chen, Yuqin; Zhao, Jingkun +4 more
Since Gaia DR2 was released, many velocity structures in the disk have been revealed, such as large-scale ridge-like patterns in phase space. Both kinematic information and stellar elemental abundances are needed to reveal their evolution history. We have used labels from the APOGEE survey to predict elemental abundances for a huge amount of low-r…
Long-term stellar variability in the Galactic Centre region
Minniti, D.; Catelan, M.; Lucas, P. W. +5 more
We report the detection of variable stars within a 11.5 arcmin× 11.5 arcmin region near the Galactic Centre that includes the Arches and Quintuplet clusters, as revealed by the VISTA Variables in the Vía Láctea survey. There are 353 sources that show KS-band variability, of which the large majority (81 per cent) correspond to red giant …