Search Publications
Timing argument take on the Milky Way and Andromeda past encounter
Benisty, David
The two-body problem of the M 31 and Milky Way (MW) galaxies with a cosmological constant background is studied, with an emphasis on the possibility that they experienced a past encounter (PE). Past encounters are possible only for a nonzero transverse velocity, and their viability is subject to observations of the imprints of such near collisions…
A faint companion around CrA-9: protoplanet or obscured binary?
Lodato, G.; Pinte, C.; Casassus, S. +16 more
Understanding how giant planets form requires observational input from directly imaged protoplanets. We used VLT/NACO and VLT/SPHERE to search for companions in the transition disc of 2MASS J19005804-3645048 (hereafter CrA-9), an accreting M0.75 dwarf with an estimated age of 1-2 Myr. We found a faint point source at ∼0.7-arcsec separation from Cr…
LOFAR Observations of a Jet-driven Piston Shock in the Low Solar Corona
Gallagher, Peter T.; Zucca, Pietro; Carley, Eoin P. +2 more
The Sun produces highly dynamic and eruptive events that can drive shocks through the corona. These shocks can accelerate electrons, which result in plasma emission in the form of a type II radio burst. Despite the large number of type II radio burst observations, the precise origin of coronal shocks is still subject to investigation. Here, we pre…
A SOPHIE RV search for giant planets around young nearby stars (YNS). A combination with the HARPS YNS survey
Meunier, N.; Messina, S.; Lagrange, A. -M. +9 more
Context. The search of close (a ≲ 5 au) giant planet (GP) companions with radial velocity (RV) around young stars and the estimate of their occurrence rates is important to constrain the migration timescales. Furthermore, this search will allow the giant planet occurrence rates to be computed at all separations via the combination with direct imag…
ATOMIUM: halide molecules around the S-type AGB star W Aquilae
Waters, L. B. F. M.; Menten, K. M.; Sahai, R. +36 more
Context. S-type asymptotic giant branch (AGB) stars are thought to be intermediates in the evolution of oxygen- to carbon-rich AGB stars. The chemical compositions of their circumstellar envelopes are also intermediate but have not been studied in as much detail as their carbon- and oxygen-rich counterparts. W Aql is a nearby S-type star, with wel…
The sun as a significant agent provoking earthquakes
Preka-Papadema, P.; Mavromichalaki, H.; Anagnostopoulos, G. +3 more
In this paper we provide significant evidence that the sun is a principal agent provoking seismic activity. In particular the aim of the studies presented is to examine the possible relation of the coronal hole (CH) driven high speed solar wind streams (HSSs) with seismicity We performed several statistical studies of solar space and seismological…
Modeling the nonaxisymmetric structure in the HD 163296 disk with planet-disk interaction
Dullemond, C. P.; Kley, W.; Weber, P. +2 more
Context. High-resolution ALMA observations such as the DSHARP campaign have revealed a variety of rich substructures in numerous protoplanetary disks. These structures consist of rings, gaps, and asymmetric features. It has been debated whether planets can be accounted for among these substructures in the dust continuum. Characterizing the origin …
Observations of the Quiet Sun during the Deepest Solar Minimum of the Past Century with Chandrayaan-2 XSM: Elemental Abundances in the Quiescent Corona
Joshi, Bhuwan; Janardhan, P.; Bhardwaj, Anil +12 more
Elements with low first ionization potential (FIP) are known to be 3-4 times more abundant in active region loops of the solar corona than in the photosphere. There have been observations suggesting that this observed "FIP bias" may be different in other parts of the solar corona and such observations are thus important in understanding the underl…
Optical and ultraviolet pulsed emission from an accreting millisecond pulsar
D'Avanzo, P.; Campana, S.; Stella, L. +28 more
Millisecond spinning, low-magnetic-field neutron stars are believed to attain their fast rotation in a 0.1-1-Gyr-long phase during which they accrete matter endowed with angular momentum from a low-mass companion star1. Despite extensive searches, coherent periodicities originating from accreting neutron star magnetospheres have been de…
X-Ray and Radio Bursts from the Magnetar 1E 1547.0-5408
Tiengo, A.; Stella, L.; Rea, N. +10 more
We report on simultaneous radio and X-ray observations of the radio-emitting magnetar 1E 1547.0-5408 on 2009 January 25 and February 3, with the 64 m Parkes radio telescope and the Chandra and XMM-Newton X-ray observatories. The magnetar was observed in a period of intense X-ray bursting activity and enhanced X-ray emission. We report here on the …