Search Publications
Mapping young stellar populations toward Orion with Gaia DR1
Brown, A. G. A.; Manara, C. F.; de Zeeuw, P. T. +2 more
In this work we use the first data release of the Gaia mission to explore the three-dimensional arrangement and age ordering of the many stellar groups toward the Orion OB association, aiming at a new classification and characterization of the stellar population not embedded in the Orion A and B molecular clouds. We make use of the parallaxes and …
HR-COSMOS: Kinematics of star-forming galaxies at z 0.9
Ilbert, O.; Scoville, N.; Zamorani, G. +5 more
We present the kinematic analysis of a sub-sample of 82 galaxies at 0.75 < z < 1.2 from our new survey HR-COSMOS aimed to obtain the first statistical sample to study the kinematics of star-forming galaxies in the treasury COSMOS field at 0 < z < 1.2. We observed 766 emission line galaxies using the multi-slit spectrograph ESO-VLT/VIMO…
Four-month chromospheric and coronal activity cycle in τ Boötis
Schmitt, J. H. M. M.; Robrade, J.; Schröder, K. -P. +3 more
We have used our robotic TIGRE facility to closely monitor the star τ Boo during the last three observing seasons 2013-2016 and to determine its S-index variability from the strength of its Ca II H and K line cores in order to study its characteristic cyclic chromospheric variations and determine its rotation period. We furthermore reanalyze archi…
Excitation and evolution of vertically polarised transverse loop oscillations by coronal rain
Kohutova, P.; Verwichte, E.
Context. Coronal rain is composed of cool dense blobs that form in solar coronal loops and are a manifestation of catastrophic cooling linked to thermal instability. The nature and excitation of oscillations associated with coronal rain is not well understood.
Aims: We consider observations of coronal rain in a bid to elucidate the excitation…
X-ray burst-induced spectral variability in 4U 1728-34
Sánchez-Fernández, C.; Kuulkers, E.; Poutanen, J. +1 more
Aims: INTEGRAL has been monitoring the Galactic center region for more than a decade. Over this time it has detected hundreds of type-I X-ray bursts from the neutron star low-mass X-ray binary 4U 1728-34, also known as the slow burster. Our aim is to study the connection between the persistent X-ray spectra and the X-ray burst spectra in a br…
Multi-instrument observations of a failed flare eruption associated with MHD waves in a loop bundle
Del Zanna, G.; Nakariakov, V. M.; Polito, V. +1 more
Context. We present observations of a B7.9-class flare that occurred on the 24th January, 2015, using the Atmospheric Imaging Assembly (AIA) of the Solar Dynamics Observatory (SDO), the EUV Imaging Spectrometer (EIS) and the X-Ray Telescope of Hinode. The flare triggers the eruption of a dense cool plasma blob as seen in AIA 171 Å, which is unable…
The ALMA Frontier Fields Survey. II. Multiwavelength Photometric analysis of 1.1 mm continuum sources in Abell 2744, MACSJ0416.1-2403 and MACSJ1149.5+2223
Kneissl, R.; Demarco, R.; Treister, E. +32 more
Context. The Hubble and Spitzer Space Telescope surveys of the Frontier Fields provide extremely deep images around six massive, strong-lensing clusters of galaxies. The ALMA Frontier Fields survey aims to cover the same fields at 1.1 mm, with maps reaching (unlensed) sensitivities of <70 µJy, in order to explore the properties of backgro…
Belt(s) of debris resolved around the Sco-Cen star HIP 67497
Pinte, C.; Ménard, F.; van der Plas, G. +15 more
Aims: In 2015, we initiated a survey of Scorpius-Centaurus A-F stars that are predicted to host warm-inner and cold-outer belts of debris similar to the case of the system HR 8799. The survey aims to resolve the disks and detect planets responsible for the disk morphology. In this paper, we study the F-type star HIP 67497 and present a first-…
A gas density drop in the inner 6 AU of the transition disk around the Herbig Ae star HD 139614 . Further evidence for a giant planet inside the disk?
Pinte, C.; Kamp, I.; Thi, W. F. +16 more
Context. Quantifying the gas surface density inside the dust cavities and gaps of transition disks is important to establish their origin.
Aims: We seek to constrain the surface density of warm gas in the inner disk of HD 139614, an accreting 9 Myr Herbig Ae star with a (pre-)transition disk exhibiting a dust gap from 2.3 ± 0.1 to 5.3 ± 0.3 A…
A distinct magnetic property of the inner penumbral boundary. II. Formation of a penumbra at the expense of a pore
Jurčák, J.; Bello González, N.; Schlichenmaier, R. +1 more
Context. We recently presented evidence that stable umbra-penumbra boundaries are characterised by a distinct canonical value of the vertical component of the magnetic field, Bstablever. In order to trigger the formation of a penumbra, large inclinations in the magnetic field are necessary. In sunspots, the penumbra develops …