Search Publications
Integral field spectroscopy in the near infrared of NGC 3125-A and SBS 0335-052
Sauvage, M.; Cresci, G.; Thompson, R. +1 more
We present integral field spectroscopy in the near infrared of the nearby dwarf starburst galaxy NGC 3125-A and of the low metallicity dwarf galaxy SBS 0335-052. The use of adaptive optics in the observations produces sub-arcsecond angular resolution. We pinpoint the star forming cores of both galaxies, identify relevant ISM components such as dus…
Long-period variables in the CoRoT fields
Lebzelter, T.
Aims: We searched the first set of data released by the CoRoT mission for red stars showing long-period variability (LPV). These stars are likely highly evolved stars on the upper giant branch. The high time resolution of the CoRoT data allows us to study the light curves of these variables in unprecedented detail.
Methods: Light curves …
A parsec-scale outflow from the luminous YSO IRAS 17527-2439
Varricatt, W. P.
Aims: We seek to understand the way massive stars form. The case of a luminous YSO IRAS 17527-2439 is studied in the infrared.
Methods: Imaging observations of IRAS 17527-2439 are obtained in the near-IR JHK photometric bands and in a narrow-band filter centred at the wavelength of the H2 1-0S(1) line. The continuum-subtracted…
Kinematics and stellar population of NGC 4486A
Prugniel, Ph.; Zeilinger, W.; Koleva, M. +1 more
Context. NGC 4486A is a low-luminosity elliptical galaxy harbouring an edge-on nuclear disk of stars and dust. It is known to host a super-massive black hole.
Aims: We study its large-scale kinematics and stellar population along the major axis to investigate the link between the nuclear and global properties.
Methods: We use long-slit m…
An intrinsic source of reddening in the cataclysmic variable SS Cygni
Gaudenzi, S.; Giovannelli, F.; Lombardi, R. +2 more
By using the INES archive of the IUE satellite, we analyzed the spectra of SS Cygni in quiescence in order to determine the value of the reddening of the binary system. The reddening of the system is reported in the literature with values that vary significantly from one another. The results demonstrate that the reddening is comprised by two compo…
A photometric long-term study of chemically peculiar stars in open clusters
Fossati, L.; Heiter, U.; Paunzen, E. +5 more
Context. Photometric variability of chemically peculiar (CP) stars of the upper main sequence is closely connected to their local stellar magnetic field and their rotational period. Long term investigations, as presented here, help us to identify possible stellar cycles (as in the Sun). Furthermore, these data provide a basis for detailed surface …
The populations of hard X-ray and γ-ray sources: a correlation study and new possible identifications
Cusumano, G.; Tramacere, A.; La Parola, V. +4 more
Aims: We present the results of our analysis devoted to researching Galactic and extragalactic sources emitting in the energy bands surveyed by both the Swift-BAT and the Fermi-LAT telescopes.
Methods: We cross-correlated the Fermi-LAT 1-year point source catalogue (1FGL) of gamma-ray sources and the second Palermo BAT catalogue (2PBC) o…
VLT adaptive optics search for luminous substructures in the lens galaxy towards SDSS J0924+0219
Faure, C.; Meylan, G.; Courbin, F. +4 more
The anomalous flux ratios between quasar images are suspected of being caused by substructures in lens galaxies. We present new deep and high-resolution H and Ks imaging of the strongly lensed quasar SDSS J0924+0219 obtained using the ESO VLT with adaptive optics and the laser guide star system. SDSS J0924+0219 is particularly interesting because …
INTEGRAL observations of the GeV blazar PKS 1502+106 and the hard X-ray bright Seyfert galaxy Mkn 841
Maraschi, L.; Tagliaferri, G.; Ghisellini, G. +15 more
Context. Extragalactic nuclear activity is most effectively explored with observations at high energies, where the most extreme flux and spectral variations are expected to occur, because of changes in either the accretion flow or the kinematics of the plasma. In active galactic nuclei of blazar type, these variations are the most dramatic.
A…
A current sheet traced from the Sun to interplanetary space
Zhao, H.; Wang, J. X.; Wheatland, M. S. +2 more
Context. Magnetic reconnection is a central concept for understanding solar activity, including filament eruptions, flares, and coronal mass ejections (CMEs). The existence of transverse and vertical current sheets, sites where reconnection takes place in the solar atmosphere, is frequently proposed as a precondition for flare/CME models, but is r…