Search Publications
A new search strategy for microquasar candidates using NVSS/2MASS and XMM-Newton data
Combi, J. A.; Martí, J.; Albacete-Colombo, J. F.
Aims:Microquasars are ideal natural laboratories for understanding accretion/ejection processes, studying the physics of relativistic jets, and testing gravitational phenomena. Nevertheless, these objects are difficult to find in our Galaxy. The main goal of this work is to increase the number of known systems of this kind, which should allow bett…
The properties of the putative pulsar associated with IGR J18135-1751/HESS J1813-178
Hill, A. B.; Dean, A. J.
Context: We investigate the possible theoretical properties of the putative pulsar associated with the pulsar wind nebula IGR J18135-1751/HESS J1813-178 based upon recent γ-ray observations and archival multi-wavelength observations.
Aims: We show that when using the standard equations for magnetic dipole radiation with recent soft γ-ray obser…
Quasar host galaxies in the FORS deep field
Nilsson, K.; Villforth, C.; Heidt, J.
Context: The evolution of quasar host galaxies is still hardly studied at high redshifts (z>2), although this is a very interesting redshift range as both the quasar activity and the star formation rate density have their peak at z≈ 2{-}3. This makes it especially interesting to study properties of quasar host galaxies, such as the star formati…
The enigmatic young object: Walker 90/V590 Monocerotis
McCollum, B.; van den Ancker, M. E.; Joner, M. D. +1 more
Aims: We assess the evolutionary status of the intriguing object Walker 90/V590 Mon, which is located about 20 arcmin northwest of the Cone Nebula near the center of the open cluster NGC 2264. This object, according to its most recent optical spectral type determination (B7), which we confirmed, is at least 3 mag too faint in V for the cluster dis…
XMM-Newton observations of the low-mass X-ray binary XB 1832-330 in the galactic globular cluster NGC 6652
Parmar, A. N.; Sidoli, L.; La Palombara, N. +1 more
Context: We report on two XMM-Newton observations performed in 2006 of the luminous low-mass X-ray binary XB 1832-330, which is located in the galactic globular cluster NGC 6652 and is probably an ultracompact binary (orbital period, P_orb, of <1 h).
Aims: The aim of these observations is to investigate the low-energy absorption towards XB …
Diagnostics of inhomogeneous stellar jets. Convolution effects and data reconstruction
Raga, A. C.; Del Burgo, C.; de Colle, F.
Context: In the interpretation of stellar jet observations, the physical parameters are usually determined from emission line ratios, obtained from spectroscopic observations or using the information contained in narrow band images. The basic hypothesis in the interpretation of the observations is that the emitting region is homogeneous along the …
Ground-based variability surveys towards Centaurus A: worthwhile or not?
Héraudeau, P.; de Jong, J. T. A.; Kuijken, K. H.
Context: Difference imaging has proven to be a powerful technique for detecting and monitoring the variability of unresolved stellar sources in M 31. Using this technique in surveys of galaxies outside the Local Group could have many interesting applications.
Aims: The goal of this paper is to test difference imaging photometry on Centaurus A,…
Radiance and Doppler shift distributions across the network of the quiet Sun
Tu, C. -Y.; Tian, H.; He, J. -S. +1 more
Aims: The radiance and Doppler-shift distributions across the solar network provide observational constraints of two-dimensional modeling of transition-region emission and flows in coronal funnels. These distributions have not, however, been studied in detail and we attempt an investigation for a quiet Sun region.
Methods: Two different method…
The complex galaxy cluster Abell 514: New results obtained with the XMM-Newton satellite
Schindler, S.; Gitti, M.; Dolag, K. +1 more
Aims: We study the X-ray morphology and dynamics of the galaxy cluster Abell 514. Also, the relation between the X-ray properties and Faraday Rotation measures of this cluster are investigated in order to study the connection of magnetic fields and the intra-cluster medium.
Methods: We use two combined XMM-Newton pointings that are split into …
The unusual UV continuum of quasar Ton 34 and the possibility of crystalline dust absorption
Binette, L.; Krongold, Y.
Context: Luminous quasars are known to display a sharp steepening of the continuum near 1100 Å. This spectral feature is not well fitted by current accretion disk models, unless Comptonization of the disk emission is invoked. Absorption by carbon crystalline dust has been proposed to account for this feature.
Aims: Ton 34 (zq = 1.92…