Search Publications
Multi-season optical modulation phased with the orbit of the super-Earth 55 Cancri e
Fossati, L.; Winn, J. N.; Lendl, M. +13 more
Context. 55 Cnc e is a transiting super-Earth orbiting a solar-like star with an orbital period of 17.7 h. In 2011, using the Microvariability and Oscillations in Stars (MOST) space telescope, a quasi-sinusoidal modulation in flux was detected with the same period as the planetary orbit. The amplitude of this modulation was too large to be explain…
Probing Polaris' puzzling radial velocity signals. Pulsational (in-)stability, orbital motion, and bisector variations
Anderson, R. I.
We investigate temporally changing variability amplitudes and the multi-periodicity of the type-I Cepheid Polaris using 161 high-precision radial velocity (RV) and bisector inverse span (BIS) measurements based on optical spectra recorded using Hermes at the 1.2 m Flemish Mercator telescope on La Palma, Canary Islands, Spain. Using an empirical te…
Towards sub-kpc scale kinematics of molecular and ionized gas of star-forming galaxies at z ∼ 1
Chisholm, J.; Schaerer, D.; Dessauges-Zavadsky, M. +4 more
We compare the molecular and ionized gas kinematics of two strongly lensed galaxies at z ∼ 1 that lie on the main sequence at this redshift. The observations were made with ALMA and MUSE, respectively. We derive the CO and [O II] rotation curves and dispersion profiles of these two galaxies. We find a difference between the observed molecular and …
Isochrone-cloud fitting of the extended main-sequence turn-off of young clusters
Bastian, N.; Aerts, C.; Johnston, C. +1 more
Context. Extended main-sequence turn-offs (eMSTOs) are a commonly observed property of young clusters. A global theoretical interpretation for eMSTOs is still lacking, but stellar rotation is considered a necessary ingredient to explain eMSTOs.
Aims: We aim to assess the importance of core-boundary and envelope mixing in stellar interiors for…
Wide-area photometric and astrometric (Gaia DR2) study of the young cluster NGC 6530
Micela, G.; Sciortino, S.; Prisinzano, L. +1 more
Context. NGC 6530 is a young cluster, with a complex morphology and star-formation history. We present a statistical study of its global properties, using a new, large list of candidate members down to masses of 0.2-0.4 M⊙ and Gaia DR2 astrometry.
Aims: We consider a larger sky region compared to previous studies, to investigate th…
Observing the gas component of circumplanetary disks around wide-orbit planet-mass companions in the (sub)mm regime
Waters, L. B. F. M.; Woitke, P.; Kamp, I. +6 more
Context. Several detections of wide-orbit planet-mass/substellar companions around young solar-like stars were reported in the last decade. The origin of those possible planets is still unclear, but accretion tracers and VLT/SPHERE observations indicate that they are surrounded by circumplanetary material or even a circumplanetary disk (CPD).
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Dust production in the debris disk around HR 4796 A
Ménard, F.; Augereau, J. -C.; Bayo, A. +21 more
Context. Debris disks are the natural by-products of the planet formation process. Scattered or polarized light observations are mostly sensitive to small dust grains that are released from the grinding down of bigger planetesimals.
Aims: High angular resolution observations at optical wavelengths can provide key constraints on the radial and…
Investigating dynamical properties of evolved Galactic open clusters
Corradi, W. J. B.; Santos, J. F. C.; Maia, F. F. S. +1 more
Context. The stellar content of Galactic open clusters is gradually depleted during their evolution as a result of internal relaxation and external interactions. The final residues of the long-term evolution of open clusters are called open cluster remnants. These are sparsely populated structures that can barely be distinguished from the field. <…
Constraining models of activity on comet 67P/Churyumov-Gerasimenko with Rosetta trajectory, rotation, and water production measurements
Jorda, L.; Kührt, E.; Mottola, S. +11 more
Aims: We use four observational data sets, mainly from the Rosetta mission, to constrain the activity pattern of the nucleus of comet 67P/Churyumov-Gerasimenko (67P).
Methods: We developed a numerical model that computes the production rate and non-gravitational acceleration of the nucleus of comet 67P as a function of time, taking into …
Plasma properties of suprathermal electrons near comet 67P/Churyumov-Gerasimenko with Rosetta
Henri, P.; Goldstein, R.; Galand, M. +6 more
Context. The Rosetta spacecraft escorted comet 67P/Churyumov-Gerasimenko from 2014 to September 2016. The mission provided in situ observations of the cometary plasma during different phases of the cometary activity, which enabled us to better understand its evolution as a function of heliocentric distance.
Aims: In this study, different elec…