Search Publications
Weak lensing mass reconstruction of the galaxy cluster Abell 209
Becciani, U.; Radovich, M.; Mercurio, A. +3 more
Context: Weak lensing applied to deep optical images of clusters of galaxies provides a powerful tool to reconstruct the distribution of the gravitating mass associated to these structures.
Aims: We use the shear signal extracted by an analysis of deep exposures of a region centered around the galaxy cluster ABCG 209, at redshift z∼ 0.2, to de…
A probable accretion-powered X-ray pulsar in IGR J00370+6122
Kuiper, L.; Hermsen, W.; den Hartog, P. R. +2 more
Serendipitous and dedicated observations with the Rossi X-ray Timing Explorer (RXTE) and the International Gamma-Ray Astrophysics Laboratory (INTEGRAL) were analyzed to study the transient high-mass X-ray binary IGR J00370+6122, in particular to search for an accretion-powered pulsar as companion to the optically identified (Reig et al. 2005, A&am…
Discovery of an X-ray nebula around PSR J1718-3825 and implications for the nature of the γ-ray source HESS J1718-385
Carrigan, S.; Funk, S.; Gallant, Y. A. +5 more
Combined X-ray synchrotron and inverse-Compton γ-ray observations of pulsar wind nebulae (PWN) may help to elucidate the processes of acceleration and energy loss in these systems. In particular, such observations provide constraints on the particle injection history and the magnetic field strength in these objects. The newly discovered TeV γ-ray …
The 12 µm ISO-ESO-Sculptor and 24 µm Spitzer faint counts reveal a population of ULIRGs as dusty massive ellipticals. Evolution by types and cosmic star formation
Seymour, N.; Rocca-Volmerange, B.; de Lapparent, V. +1 more
Context: Multi-wavelength galaxy number counts provide clues to the nature of galaxy evolution. The interpretation per galaxy type of the mid-IR faint counts obtained with ISO and Spitzer, consistent with the analysis of deep UV-optical-near IR galaxy counts, provide new constraints on the dust and stellar emission. Discovering the nature of new p…
On the artificial nature of aperiodic variability in XMM-Newton observations of M 31 X-ray sources and the ultraluminous X-ray source NGC 4559 ULX-7
Osborne, J. P.; Barnard, R.; Kolb, U. C. +3 more
Context: Power density spectra (PDS) that are characteristic of low mass X-ray binaries (LMXBs) have been previously reported for M 31 X-ray sources, observed by XMM-Newton. However, we have recently discovered that these PDS result from the improper addition/subtraction of non-simultaneous lightcurves.
Aims: To understand the properties and o…
Star-gas decoupling and a non-rotating stellar core in He 2-10. Integral field spectroscopy with FLAMES/ARGUS
Östlin, G.; Bergvall, N.; Fathi, K. +3 more
Aims:We study the two-dimensional distribution and kinematics of the stellar and gaseous components in the centre of the blue compact dwarf galaxy He 2-10. The aim is to compare the kinematics of gas and stars in order to determine whether they are consistent with one another, or if stars and gas can be decoupled due to gravitational perturbations…
INTEGRAL-ISGRI observations of the Cygnus OB2 region. Searching for hard X-ray point sources in a region containing several non-thermal emitting massive stars
Rauw, G.; De Becker, M.; Sana, H. +3 more
Aims:We analyze INTEGRAL-ISGRI data in order to probe the hard X-ray emission (above 20 keV) from point sources in the Cyg OB2 region and to investigate the putative non-thermal high-energy emission from early-type stars (Wolf-Rayet and O-type stars). Among the targets located in the field of view, we focus on the still unidentified EGRET source 3…
HeI doubled emission lines from A0535+26 ≡ HDE 245770. A possible interpretation
Bernabei, S.; Rossi, C.; Giovannelli, F. +1 more
We report results of the spectroscopy for V725 Tau (HDE 245770, BD +26°883), commonly known as Flavia's star, which is the optical counterpart of the X-ray pulsar A0535+26, carried out at the 1.5 m Loiano telescope during one run of observations of this star spread over a period of years. The HeI emission lines clearly show doubling, which is good…
Discovery of X-ray emission from the young radio pulsar PSR J1357-6429
Tiengo, A.; de Luca, A.; Esposito, P. +1 more
We present the first X-ray detection of the very young pulsar PSR J1357-6429 (characteristic age of 7.3 kyr) using data from the XMM-Newton and Chandra satellites. We find that the spectrum is well described by a power-law plus blackbody model, with photon index Γ=1.4 and blackbody temperature k_BT=160 eV. For the estimated distance of 2.5 kpc, th…
Discovery of variable X-ray absorption in the cTTS AA Tauri
Schmitt, J. H. M. M.; Robrade, J.
We present XMM-Newton X-ray and UV observations of the classical T Tauri star AA Tau covering almost two rotational periods where P_rot ∼ 8.5 days. Clear, but uncorrelated variability is found at both wavebands. The variability observed at ~2100 Å follows the previously known optical period. Spectral analysis of the X-ray data results in significa…