Related papers: The Ionized Stellar Wind in Vela X-1 During Eclips…

Over the last 3 yrs, the Galactic center (GC) region has been monitored with the Chandra X-Ray Observatory. With 11 Chandra observations through 2002 June, the total effective exposure reaches ~590 ks, providing significant photon…

We report on our analysis of a 300 ks observation of the Vela pulsar with the Rossi X-Ray Timing Explorer (RXTE). The double-peaked, pulsed emission at 2 - 30 keV, which we had previously detected during a 93 ks observation, is confirmed…

We present the first {\it XMM-Newton} observation of the classical supergiant high-mass X-ray binary XTE J1855$-$026 taken entirely during the eclipse of the neutron star (NS), covering the orbital phases $\phi= 0.00-0.11$. The analysis of…

Marked correlations are reported between the ionization of the X-ray line spectra of normal OB stars, as observed by the Chandra X-Ray Observatory, and their optical spectral types. These correlations include the progressive weakening of…

In order to compare the x-wind with observations, one needs to be able to calculate its thermal and ionization properties. We formulate the physical basis for the streamline-by-streamline integration of the ionization and heat equations of…

The first results from a VLT-ISAAC program on L- and M-band infrared spectroscopy of deeply-embedded young stellar objects are presented. The advent of 8-m class telescopes allows high S/N spectra of low-luminosity sources to be obtained.…

Chandra observations of the Vela pulsar-wind nebula (PWN) have revealed a jet in the direction of the pulsar's proper motion, and a counter-jet in the opposite direction, embedded in diffuse nebular emission. The jet consists of a bright,…

Pulsar wind nebulae (PWNe) are among the most extreme particle accelerators in galaxies, are recognized as multi-TeV electron/positron sources, and are one of the dominant classes of Galactic gamma-ray sources. Vela X is a nearby PWN at 290…

We present disk wind model calculations for the broad emission lines seen in the ultraviolet spectra of the X-ray binary Hercules X-1. Recent HST/STIS observations of these lines suggest that they are kinematically linked to the orbital…

We present results of more than 13 years of Fermi-LAT data analysis for the Vela pulsar from 60 MeV to 100 GeV and its pulsar wind nebula (PWN), Vela-X, for E > 1 GeV in the off-pulse phases. We find the Vela-X PWN can be best characterized…

Whilst the Vela pulsar and its associated nebula are often considered as the archetype of a system powered by a \sim10^4 year old isolated neutron star, many features of the spectral energy distribution of this pulsar wind nebula are both…

We analyse two ASCA observations of the highly eccentric O9III + B1III binary Iota Orionis obtained at periastron and apastron. Based on the assumption of a strong colliding winds shock between the stellar components, we expected to see…

We report on INTEGRAL/IBIS observations of the Vela region during a Galactic Plane Scan (hereafter GPS) presenting the IBIS in-flight performances during these operations. Among all the known sources in the field of view we clearly detect…

Vela X is the prototypical example of a pulsar wind nebula whose morphology and detailed structure have been affected by the interaction with the reverse shock of its host supernova remnant. The resulting complex of filamentary structure…

Vela X is a pulsar wind nebula in which two relativistic particle populations with distinct spatial and spectral distributions dominate the emission at different wavelengths. An extended $2^\circ \times 3^\circ$ nebula is seen in radio and…

We present a preliminary analysis of the 1--10 keV spectrum of the massive X-ray binary Cyg X-3, obtained with the High Energy Transmission Grating Spectrometer on the Chandra X-ray Observatory. The source reveals a richly detailed discrete…

\mu\ Columbae is a prototypical weak-wind O-star for which we have obtained a high-resolution X-ray spectrum with the Chandra LETG/ACIS-S instrument and a low resolution spectrum with Suzaku. This allows us, for the first time, to…

(Abridged) We present the results from a detailed analysis of the 0.6 - 10 keV spectra of 23 ASCA observations of 18 objects. We find that in most cases the underlying continuum can be well-represented by a powerlaw with a photon index…

The observations of the pulsar-wind nebula (PWN) around the Vela pulsar with the Advanced CCD Imaging Spectrometer aboard the Chandra X-ray Observatory, taken on 2000 April 30 and November 30, reveal its complex morphology reminiscent of…

We report the first detection of highly ionized Fe species in the X-ray spectrum of the eclipsing and dipping Low Mass X-ray Binary XTE J1710-281. Using archival Chandra and Suzaku observations, we have carried out a spectro-timing analysis…