Search Publications
On the dynamical stability of the Rosetta orbiter. II.
Mysen, E.; Aksnes, K.
In an orbit around a comet, a spacecraft is subject to several spin-orbit resonances. These enhanced couplings, induced by the rotation of the nucleus, by temporal variations in the outgassing pressure field and, at last, by a rotation of the probe's solar cell arrays, are systematically mapped in this paper. Using the simplified pendulum model, e…
Optical astrometric positions of 59 northern ICRF radio sources
Assafin, M.; Camargo, J. I. B.; Andrei, A. H. +5 more
Context: To investigate the link between the International Celestial Reference Frame (ICRF) and its optical Hipparcos-based representation on the northern hemisphere.
Aims: To present results of a pilot investigation on the astrometry of 59 northern ICRF sources.
Methods: We used the 0.6 m Zeiss telescope at Belogradchik Observatory, Bulga…
ARCRAIDER. I. Detailed optical and X-ray analysis of the cooling flow cluster Z3146
Schindler, S.; Erben, T.; Gitti, M. +1 more
We present a detailed analysis of the medium redshift (z = 0.2906) galaxy cluster Z3146 which is part of the ongoing ARCRAIDER project, a systematic search for gravitational arcs in massive clusters of galaxies. The analysis of Z3146 is based on deep optical wide field observations in the B, V and R bands obtained with the WFI@ESO2.2m, and shallow…
Chandra X-ray counterpart of KS 1741-293
Pérez-Ramírez, D.; Combi, J. A.; Martí, J. +4 more
Aims:We aim to investigate the nature of the high energy source KS 1741-293 by revisiting the radio and infrared associations proposed in the early 1990s.
Methods: Our work is mostly based on the analysis of modern survey and archive data, including the NRAO, MSX, 2MASS and Chandra archives, and catalogues. We also have obtained deep CCD optic…
The luminous infrared composite Seyfert 2 galaxy NGC 7679 through the [O III] λ 5007 emission line
Jockers, K.; Yankulova, I. M.; Golev, V. K.
Context:
Spatial damping of compressional MHD waves in prominences
Dwivedi, B. N.; Singh, K. A. P.; Hasan, S. S.
Aims:We study the spatial damping of linear compressional MHD waves in a homogeneous, isothermal, and unbounded prominence.
Methods: We derive a general dispersion relation invoking the Newtonian radiation and turbulent viscosity. The turbulent viscosity is derived from SUMER and CDS observations for Kraichnan and Kolmogorov turbulences. Since…
The ISOPHOT 170 µm Serendipity Survey. III. FIR statistics of optically identified galaxies
Lemke, D.; Klaas, U.; Stickel, M.
Aims: To shed more light on the integrated FIR properties of galaxies, the ≈2000 compact sources in the ISOPHOT Serendipity Survey associated with identified galaxies are investigated statistically. They provide the only sample large enough to determine the FIR properties such as dust temperatures and masses, FIR luminosities, and HI-to-dust ratio…
An X-ray survey in SA 57 with XMM-Newton
Fiore, F.; Puccetti, S.; Trevese, D. +3 more
Context: The maximum number density of Active Galactic Nuclei (AGNs), as deduced from X-ray studies, occurs at z ⪉ 1, with lower luminosity objects peaking at smaller redshifts. Optical studies lead to a different evolutionary behaviour, with a number density peaking at z ≈ 2 independently of the intrinsic luminosity, but this result is limited to…
Multi-component absorption lines in the HST spectra of α Scorpii B
Reimers, D.; Baade, R.
Context: Extended atmospheres of late-type supergiants are of special interest with regard to the mass-loss process, the circumstellar physico-chemistry, and the evolution of stars.
Aims: The circumstellar envelope of α Sco A (M1.5 Iab) has been subject of intensive studies. Nevertheless the mechanism that is responsible for the mass outflow i…
The baryon density at z = 0.9-1.9. Tracing the warm-hot intergalactic medium with broad Lyman α absorption
Reimers, D.; Janknecht, E.; Prause, N. +1 more
Aims:We present an analysis of the Lyman α forests of five quasar spectra in the near UV. Properties of the intergalactic medium (IGM) at an intermediate redshift interval (0.9≤ z≤1.9) are studied. The amount of baryons in the diffuse photoionised IGM and the warm-hot intergalactic medium (WHIM) are traced to get constraints on the redshift evolut…