Related papers: The variable, fast soft X-ray wind in PG 1211+143

We present Chandra X-ray observations of the radio-quiet QSO PG 2302+029. This quasar has a rare system of ultra-high velocity (-56,000 km/s) UV absorption lines that form in an outflow from the active nucleus (Jannuzi et al. 2003). The…

Our goal is to understand the specificities of highly absorbed sgHMXB and in particular of the companion stellar wind, thought to be responsible for the strong absorption. We have monitored IGR J17252-3616, a highly absorbed system…

We present the timing analysis of the four archived XMM-Newton observations of PG 1211+143. The source is well-known for its spectral complexity, comprising a strong soft-excess and different absorption systems. Soft energy band (0.3-0.7…

Transient X-ray obscuration in Seyfert 1 galaxies is thought to arise from clumpy accretion-disk winds near the broad-line region (BLR), but the wind structure and its short-timescale variability are difficult to measure because…

We observed the black hole candidate Cyg X-1 for 15 ks with the High-Energy Transmission Grating Spectrometer aboard the CHANDRA X-ray Observatory. The source was observed during a period of intense flaring activity, so it was about a…

We present a moderate-resolution (~20 km/s) spectrum of the mini broad-absorption-line QSO PG1351+64 between 915-1180 A, obtained with the Far Ultraviolet Spectroscopic Explorer (FUSE). Additional spectra at longer wavelengths were also…

We present a study of X-ray ionization of magnetohydrodynamic (MHD) accretion-disk winds in an effort to constrain the physics underlying the highly-ionized ultra-fast outflows (UFOs) inferred by X-ray absorbers often detected in various…

We analyze the broad-band X-ray spectrum (0.3-50 keV) of the luminous Seyfert 1 / quasar PG 1211+143 - the archetypal source for high-velocity X-ray outflows - using near-simultaneous XMM-Newton and NuSTAR observations. We compare pure…

The X-ray flux of Nova V2491 Cyg reached a maximum some forty days after optical maximum. The X-ray spectrum at that time, obtained with the RGS of XMM-Newton, shows deep, blue-shifted absorption by ions of a wide range of ionization. We…

We present a spectral analysis of a brief Chandra/HETG observation of the neutron star low-mass X-ray binary GX~340+0. The high-resolution spectrum reveals evidence of ionized absorption in the Fe K band. The strongest feature, an…

The XMM-Newton spectrum of the black hole candidate XTE J1652-453 shows a broad and strong Fe K-alpha emission line, generally believed to originate from reflection of the inner accretion disc. These data have been analysed by Hiemstra et…

The Seyfert Galaxy Mrk 335 is known for its frequent changes of flux and spectral shape in the X-ray band occurred during recent years. These variations may be explained by the onset of a wind that previous, non-contemporaneous…

We present results based on an XMM-Newton observation of the high luminosity narrow-line QSO PHL 1092 performed in 2003 January. The 0.3 - 10 keV spectrum is well described by a model which includes a power-law (Gamma ~ 2.1) and two…

We report the results from a recent 133 ks XMM-Newton observation of a highly super-Eddington narrow-line Type-1 QSO RX J0439.6-5311. This source has one of the steepest AGN hard X-ray slopes, in addition to a prominent and smooth soft…

There exists a significant population of broad line, z~2 QSOs which have heavily absorbed X-ray spectra. Follow up observations in the submillimetre show that these QSOs are embedded in ultraluminous starburst galaxies, unlike most…

We present the analysis and the results of a 20 ks XMM-Newton observation of the extremely X-ray loud (L_X ~ 5 x 10^{47} erg/s) flat-spectrum radio quasar RBS 315 at a redshift of 2.69. This EPIC observation has allowed us to strongly…

PG 1448+273 is a luminous, nearby ($z=0.0645$), narrow line Seyfert 1 galaxy, which likely accretes close to the Eddington limit. Previous X-ray observations of PG 1448 with XMM-Newton in 2017 and NuSTAR in 2022 revealed the presence of an…

We present the results from a detailed analysis of the 2007 Swift monitoring campaign of the quasar PG1211+143. We constructed broad-band, optical/UV/X-ray spectral energy distributions over three X-ray flux intervals. We fitted them with a…

We present an XMM-Newton observation of NGC 7469, including studies of the X-ray and UV variability, 0.2-10 keV spectral continuum, Fe K-alpha emission line and the first-ever high-resolution X-ray spectrum of the soft X-ray warm absorber.…

We present optical and X-ray data for a sample of serendipitous XMM-Newton sources that are selected to have 0.5-2 keV vs 2-4.5 keV X-ray hardness ratios which are harder than the X-ray background. The sources have 2-4.5 keV X-ray flux >=…