Search Publications
Detection of Hα emission from PZ Telescopii B using SPHERE/ZIMPOL
Henning, Thomas; Musso Barcucci, Arianna; Launhardt, Ralf +6 more
Hα is a powerful tracer of accretion and chromospheric activity, which has been detected in the case of young brown dwarfs and even recently in planetary mass companions (e.g. PDS70 b and c). Hα detections and characterisation of brown dwarf and planet companions can further our knowledge of their formation and evolution, and expanding such a samp…
Kinematics and dynamics of the luminous infrared galaxy pair NGC 5257/58 (Arp 240)
Rosado, M.; Amram, P.; Fuentes-Carrera, I. +6 more
Context. Encounters between galaxies modify their morphology, kinematics, and star formation history. The relation between these changes and external perturbations is not straightforward. The great number of parameters involved requires both the study of large samples and individual encounters where particular features, motions, and perturbations …
Radio observations of evaporating objects in the Cygnus OB2 region
del Palacio, S.; Fernández-López, M.; Ishwara-Chandra, C. H. +2 more
We present observations of the Cygnus OB2 region obtained with the Giant Metrewave Radio Telescope (GMRT) at frequencies of 325 and 610 MHz. In this contribution we focus on the study of proplyd-like objects (also known as free-floating evaporating gas globules or frEGGs) that typically show an extended cometary morphology. We identify eight objec…
Strongly magnetic Ap stars in the Gaia DR2 Hertzsprung-Russell diagram . I. Selecting the most reliable astrometric and photometric data
Hubrig, S.; Chojnowski, S. Drew; Scholz, R. -D.
Context. Knowing the distribution of strongly magnetic Ap stars in the Hertzsprung-Russell diagram (HRD) allows us to study the evolution of their magnetic fields across the main sequence (MS). With a newly extended Ap star sample from APOGEE and available Gaia DR2 data, we can now critically review the results of previous studies based on HIPPARC…
Distance to the nearby dwarf galaxy [TT2009] 25 in the NGC 891 group using the tip of the red giant branch
Müller, Oliver; Ibata, Rodrigo; Rejkuba, Marina +1 more
Dwarf galaxies are key objects for small-scale cosmological tests like the abundance problems or the planes-of-satellites problem. A crucial task is therefore to get accurate information for as many nearby dwarf galaxies as possible. Using extremely deep, ground-based V and i-band Subaru Suprime Cam photometry with a completeness of i = 27 mag, we…
CSI 2264: Simultaneous optical and X-ray variability in the pre-main sequence stars of NGC 2264. II. Photometric variability, magnetic activity, and rotation in class III objects and stars with transition disks
Micela, G.; Stauffer, J.; Sciortino, S. +6 more
Context. Pre-main sequence stars are variable sources. In diskless stars this variability is mainly due to the rotational modulation of dark photospheric spots and active regions, as in main sequence stars even if associated with a stronger magnetic activity.
Aims: We aim at analyzing the simultaneous optical and X-ray variability in these st…
New composite supernova remnant toward HESS J1844-030?
Petriella, A.
Aims: HESS J1844-030 is a newly confirmed TeV source in the direction of the X-ray pulsar wind nebula (PWN) candidate G29.4+0.1 and the complex radio source G29.37+0.1, which is likely formed by the superposition of a background radio galaxy and a Galactic supernova remnant (SNR). Many scenarios have been proposed to explain the origin of HES…
A new fitting concept for the robust determination of Sérsic model parameters
Amarantidis, Stergios; Breda, Iris; Papaderos, Polychronis +1 more
Context. The Sérsic law (SL) offers a versatile, widely used functional form for the structural characterization of galaxies near and far. Whereas fitting this three-parameter function to galaxies with a genuine SL luminosity distribution (e.g., several local early-type galaxies-ETGs) yields a robust determination of the Sérsic exponent η and effe…
VEXAS: VISTA EXtension to Auxiliary Surveys. Data Release 1. The southern Galactic hemisphere
Agnello, A.; Spiniello, C.
Context. We present the first public data release of the VISTA EXtension to Auxiliary Surveys (VEXAS), comprising nine cross-matched multi-wavelength photometric catalogues where each object has a match in at least two surveys.
Aims: Our aim is to provide spatial coverage that is as uniform as possible in the multi-wavelength sky and to provi…
Properties and nature of Be stars. 31. The binary nature, light variability, physical elements, and emission-line changes of HD 81357
Frémat, Y.; Harmanec, P.; Yang, S. +10 more
Reliable determination of the basic physical properties of hot emission-line binaries with Roche-lobe filling secondaries is important for developing the theory of mass exchange in binaries. It is not easy, however, due to the presence of circumstellar matter. Here, we report the first detailed investigation of a new representative of this class o…