Search Publications
First MATISSE L-band observations of HD 179218. Is the inner 10 au region rich in carbon dust particles?
Waters, L. B. F. M.; Meisenheimer, K.; Augereau, J. -C. +58 more
Context. Carbon is one of the most abundant components in the Universe. While silicates have been the main focus of solid phase studies in protoplanetary discs (PPDs), little is known about the solid carbon content especially in the planet-forming regions (~0.1-10 au). Fortunately, several refractory carbonaceous species present C-H bonds (such as…
Photoionisation modelling of the X-ray emission line regions within the Seyfert 2 AGN NGC 1068
Bianchi, S.; Mehdipour, M.; Behar, E. +4 more
Aims: We investigate the photoionised X-ray emission line regions (ELRs) within the Seyfert 2 galaxy NGC 1068 to determine if there are any characteristic changes between observations taken 14 years apart.
Methods: We compared XMM-Newton observations collected in 2000 and 2014, simultaneously fitting the reflection grating spectrometer a…
Looking into the cradle of the grave: J22564-5910, a potential young post-merger hot subdwarf
Uzundag, Murat; Pelisoli, Ingrid; Bobrick, Alexey +10 more
Context. We present the discovery of J22564-5910, a new type of hot subdwarf (sdB) which shows evidence of gas present in the system and it has shallow, multi-peaked hydrogen and helium lines which vary in shape over time. All observational evidence points towards J22564-5910 being observed very shortly after the merger phase that formed it.
…
Inhomogeneity in the early Galactic chemical enrichment exposed by beryllium abundances in extremely metal-poor stars
Pasquini, L.; Smiljanic, R.; Zych, M. G.
Context. Abundances of beryllium in metal-poor stars scale linearly with metallicity down to [Fe/H] ∼ -3.0. In the stars where Be has been detected at this extremely metal-poor regime, an increased abundance scatter has been previously reported in the literature. This scatter could indicate a flattening of the relation between Be abundances and me…
Evolution of the truncated disc and inner hot-flow of GX 339-4
Chainakun, P.; Young, A. J.; Luangtip, W. +2 more
Aims: We study the changes in geometry of the truncated disc and the inner hot-flow of GX 339-4 by analysing the power spectral density (PSD) extracted from six XMM-Newton observations taken at the very end of an outburst.
Methods: We developed a theoretical model of the PSD of GX 339-4 in the 0.3-0.7 keV (thermal-reverberation-dominated…
HST PanCET program: non-detection of atmospheric escape in the warm Saturn-sized planet WASP-29 b
Sanz-Forcada, J.; Ehrenreich, D.; Lecavelier des Etangs, A. +10 more
Short-period gas giant exoplanets are susceptible to intense atmospheric escape due to their large scale heights and strong high-energy irradiation. This process is thought to occur ubiquitously, but to date we have only detected direct evidence of atmospheric escape in hot Jupiters and warm Neptunes. The latter planets are particularly more sensi…
Detection of H2O and OH+ in z > 3 hot dust-obscured galaxies
Knudsen, K. K.; Aalto, S.; Falstad, N. +3 more
Aims: In this paper we present the detection of H2O and OH+ emission in z > 3 hot dust-obscured galaxies (Hot DOGs).
Methods: Using ALMA Band-6 observations of two Hot DOGs, we detected H2O(202 - 111) in W0149+2350, and H2O(312 - 303) and the multi…
The evolution of lithium in FGK dwarf stars. The lithium-rotation connection and the Li desert
Cifuentes, C.; Roca-Fàbrega, S.; Llorente de Andrés, F. +2 more
We investigate two topics regarding solar mass FGK-type stars, the lithium-rotation connection (LRC), and the existence of the `lithium desert'. We determine the minimum critical rotation velocity (v sin i), related with the LRC separating slow from rapid stellar rotators, to be 5 km s−1. This value also splits different stellar propert…
Solar Orbiter observations of an ion-scale flux rope confined to a bifurcated solar wind current sheet
Eastwood, J. P.; Lavraud, B.; Horbury, T. S. +10 more
Context. Flux ropes in the solar wind are a key element of heliospheric dynamics and particle acceleration. When associated with current sheets, the primary formation mechanism is magnetic reconnection and flux ropes in current sheets are commonly used as tracers of the reconnection process.
Aims: Whilst flux ropes associated with reconnectin…
Comparison of multifrequency positions of extragalactic sources from ICRF3 and Gaia EDR3
Liu, N.; Zhu, Z.; Liu, J. -C. +5 more
Context. Comparisons of optical positions derived from the Gaia mission and radio positions measured by very long baseline interferometry (VLBI) probe the structure of active galactic nuclei (AGN) on the milliarcsecond scale. So far, these comparisons have focused on using the S∕X-band (2/8 GHz) radio positions, but did not take advantage of the V…