Search Publications
The 54-day orbital period of AX J1820.5-1434 unveiled by Swift
Campana, S.; Cusumano, G.; Masetti, N. +3 more
Context. The hard X-ray survey that Swift Burst Alert Telescope (BAT) has been performing since late 2004 provides a considerable database for a large number of sources, whose hard X-ray emission are poorly known.
Aims: We exploit the BAT survey archive to improve the temporal and spectral characterization of the Galactic hard-X-ray sources. …
Multi-band constraints on the nature of emission line galaxies
Capetti, A.; Balmaverde, B.
Our aim is to explore the nature of emission line galaxies by combining high-resolution observations obtained in different bands to understand which objects are powered by an active galactic nucleus (AGN). From the spectroscopic Palomar survey of nearby bright galaxies, we selected a sample of 18 objects observed with Hubble Space Telescope (HST),…
CV1 in the globular cluster M 22: confirming its nature through X-ray observations and optical spectroscopy
Servillat, M.; Webb, N. A.
Context. Observations of cataclysmic variables in globular clusters appear to show a dearth of outbursts compared to those observed in the field. A number of explanations have been proposed, including low mass-transfer rates and/or moderate magnetic fields implying higher mass white dwarfs than the average observed in the field. Alternatively this…
The molecular envelope of CRL 618: A new model based on Herschel/HIFI observations
Alcolea, J.; Bujarrabal, V.; Soria-Ruiz, R.
Aims: We study the physical properties and molecular excitation of the different warm gas components found in the protoplanetary nebula CRL 618. The proper study of the nebular structure and its implications on the dynamics and kinematics of the molecular gas are of particular importance for understanding the evolution of these objects.
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Mid-infrared observations of the circumstellar disks around PDS 66 and CRBR 2422.8-3423
Wolf, S.; Gräfe, C.
Aims: We present mid-infrared observations and photometry of the circumstellar disks around
Stray-light correction in 2D spectroscopy
Franz, M.; Schlichenmaier, R.
Context. In solar physics, spectropolarimeters based on Fabry-Pérot interferometers are commonly used for high spatial resolution observations. In the data pipeline, corrections for scattered light may be performed on each narrow band image.
Aims: We elaborate on the effects of stray-light corrections on Doppler maps.
Methods: First, we …
Deep optical imaging of the γ-ray pulsar J1048-5832 with the VLT
Sollerman, J.; Kirichenko, A.; Zyuzin, D. +2 more
Context. PSR J1048-5832 is a young radio-pulsar that has recently been detected in γ-rays with Fermi, and also in X-rays with Chandra and XMM-Newton. It powers a compact pulsar wind nebula visible in X-rays and is in many ways similar to the Vela pulsar.
Aims: We present deep optical observations made with the ESO Very Large Telescope to sear…
Star forming regions in a sample of HST spiral galaxies
Dapergolas, A.; Kontizas, M.; Kontizas, E. +2 more
Aims: The presence of small- and large-scale star formation structures in a sample of six spiral Hubble Space Telescope (HST) galaxies is investigated to identify small structures of young stars known as OB associations and to tell whether they are formed inside larger scale star forming stellar structures in a hierarchical form.
Methods…
Cosmological model dependence of the galaxy luminosity function: far-infrared results in the Lemaître-Tolman-Bondi model
Berta, S.; Magnelli, B.; Nordon, R. +9 more
Aims: This is the first paper of a series aiming at investigating galaxy formation and evolution in the giant-void class of the Lemaître-Tolman-Bondi (LTB) models that best fits current cosmological observations. Here we investigate the luminosity function (LF) methodology, and how its estimates would be affected by a change on the cosmologic…
Astrometric mass ratios for three spectroscopic binaries
Sahlmann, J.; Fekel, F. C.
The orbits of five single-lined spectroscopic binaries have recently been determined. We now use astrometric measurements that were collected with the Hipparcos satellite to constrain the systems' mass ratios and secondary masses. The barycentric astrometric orbits of three binary systems, HD 140667, HD 158222, and HD 217924, are fully determined …