Search Publications
The impact of massive stars and black holes on the fate of open star clusters and their tidal streams
Wang, Long; Jerabkova, Tereza
Context. We use present-day observations to investigate how the content of massive OB stars affects the long-term evolution of young open clusters and their tidal streams, and how such an effect influences the constraint of initial conditions.
Aims: OB stars are typically found in binaries. They have a strong wind mass loss during the first f…
UVES analysis of red giants in the bulge globular cluster NGC 6522
Chiappini, C.; Bica, E.; Barbuy, B. +10 more
Context. NGC 6522 is a moderately metal-poor bulge globular cluster ([Fe/H] ~ −1.0), and it is a well-studied representative among a number of moderately metal-poor blue horizontal branch clusters located in the bulge. The NGC 6522 abundance pattern can give hints on the earliest chemical enrichment in the central Galaxy.
Aims: The aim of thi…
S stars and s-process in the Gaia era. II. Constraining the luminosity of the third dredge-up with Tc-rich S stars
Van Winckel, Hans; Wallerstein, George; Plez, Bertrand +6 more
Context. S stars are late-type giants that are transition objects between M-type stars and carbon stars on the asymptotic giant branch (AGB). They are classified into two types: intrinsic or extrinsic, based on the presence or absence of technetium (Tc). The Tc-rich or intrinsic S stars are thermally pulsing (TP-)AGB stars internally producing s-p…
Plasma densities, flow, and solar EUV flux at comet 67P. A cross-calibration approach
Nilsson, H.; Henri, P.; Edberg, N. J. T. +7 more
Context. During its two-year mission at comet 67P, Rosetta nearly continuously monitored the inner coma plasma environment for gas production rates varying over three orders of magnitude, at distances to the nucleus ranging from a few to a few hundred kilometres. To achieve the best possible measurements, cross-calibration of the plasma instrument…
Testing the models of X-ray driven photoevaporation with accreting stars in the Orion Nebula Cluster
Manara, C. F.; Preibisch, T.; Ercolano, B. +1 more
Context. Recent works highlight the importance of stellar X-rays on the evolution of the circumstellar disks of young stellar objects, especially for disk photoevaporation.
Aims: A signature of this process may be seen in the so far tentatively observed dependence of stellar accretion rates on X-ray luminosities. According to models of X-ray …
Combining magneto-hydrostatic constraints with Stokes profiles inversions. II. Application to Hinode/SP observations
Pastor Yabar, A.; Ruiz Cobo, B.; Borrero, J. M.
Context. Inversion techniques applied to the radiative transfer equation for polarized light are capable of inferring the physical parameters in the solar atmosphere (temperature T, magnetic field B, and line-of-sight velocity vlos) from observations of the Stokes vector (i.e., spectropolarimetric observations) in spectral lines. Infere…
The Hubble PanCET program: long-term chromospheric evolution and flaring activity of the M dwarf host GJ 3470
Sanz-Forcada, J.; Ehrenreich, D.; Bourrier, V. +9 more
Neptune-size exoplanets seem particularly sensitive to atmospheric evaporation, making it essential to characterize the stellar high-energy radiation that drives this mechanism. This is particularly important with M dwarfs, which emit a large and variable fraction of their luminosity in the ultraviolet and can display strong flaring behavior. The …
Frequencies, chaos, and resonances: A study of orbital parameters of nearby thick-disc and halo stars
Helmi, Amina; Koppelman, Helmer H.; Hagen, Jorrit H. J.
Aims: We study the distribution of nearby thick-disc and halo stars in subspaces defined by their characteristic orbital parameters. Our aim is to establish the origin of the structure reported in particular in the Rmax - zmax space.
Methods: To this end, we computed the orbital parameters and frequencies of stars f…
Extended envelopes around Galactic Cepheids. V. Multi-wavelength and time-dependent analysis of IR excess
Kervella, P.; Mérand, A.; Lagadec, E. +6 more
Aims: We aim to investigate the infrared excess of 45 Milky Way (MW) Cepheids combining different observables in order to constrain the presence of circumstellar envelopes (CSEs).
Methods: We used the SpectroPhoto-Interferometry of Pulsating Stars (SPIPS) algorithm, a robust implementation of the parallax-of-pulsation method that combine…
Search for candidate strongly lensed dusty galaxies in the Planck satellite catalogues
Burigana, C.; Herranz, D.; Trombetti, T. +5 more
The shallow, all-sky Planck surveys at sub-millimetre wavelengths have detected the brightest strongly gravitationally lensed dusty galaxies in the sky. The combination of their extreme gravitational flux-boosting and image-stretching offers the unique possibility of measuring in extraordinary detail the galaxy structure and kinematics in early ev…