Related papers: The column density towards LMC X-1
We present soft X-ray spectroscopy of the black hole binary LMC X-3 from the XMM-Newton Reflection Grating Spectrometer. The observations span the full range of spectral states seen in LMC X-3. The spectra are completely dominated by…
We have observed with XMM-Newton four radiatively efficient active type 1 galaxies with black hole masses < 10^6 Msun, selected optically from the SDSS. We show here that their soft X-ray spectrum exhibits a soft excess with the same…
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…
High-mass X-ray binary systems are powered by the stellar wind of their donor stars. The X-ray state of Cygnus X-1 is correlated with the properties of the wind which defines the environment of mass accretion. Chandra-HETGS observations…
We studied the X-ray dust scattering halos around 17 bright X-ray point sources using {\it Chandra} data. We use an iterative method to resolve the halos at small scattering angles from the zeroth order data in CC-mode or the first order…
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 >=…
The analysis of a series of seven observations of the nearby ($z=0.0809$) QSO, PG 1211+143, taken with the Reflection Grating Spectrometer (RGS) on-board XMM-Newton in 2014, are presented. The high resolution soft X-ray spectrum, with a…
Aim of this work is a broad-band study with INTEGRAL, Swift and XMM-Newton satellites of a sample of 9 blazars (7 FSRQ and 2 BL Lac) with redshift up to about 4. The spectral analysis has shown clear evidence of a flattening of the…
We measured the galactic hydrogen column densities to the neutron-star binaries GX 17+2, 4U 1705-44, and 4U 1728-34 by modeling the Mg and Si absorption edges found in high-resolution X-ray spectra obtained by the Chandra X-ray Observatory.…
This paper presents the results of a detailed X-ray spectral analysis of a sample of 123 X-ray sources (46 being type-1 AGN and 28 type-2 AGN) detected with XMM-Newton in the Lockman Hole field. Using a single power law model our sources'…
The absorption lines in the soft X-ray spectrum of MCG--6-30-15 are studied using the Reflection Grating Spectrometer data from the 2001 XMM-Newton 320 ks observation. A line search of the full time-averaged spectrum reveals 51 absorption…
The fraction of AGN with photoelectric absorption in the X-rays ranging from NH of 10^{22} up to about 10^{24} cm^{-2} (Compton-thin) appears observationally to be anticorrelated to their luminosity Lx. This recently found evidence is used…
Many of the high mass X-ray binaries (HMXRBs) discovered in recent years in our Galaxy are characterized by a high absorption, most likely intrinsic to the system, which hampers their detection at the softest X-ray energies. We have…
XMM-Newton spectra of five red, 2MASS AGN, selected from a sample observed by Chandra to be relatively X-ray bright and to cover a range of hardness ratios, confirm the presence of substantial absorbing material in three sources with…
Soft X-rays high resolution spectroscopy of obscured AGNs shows the existence of a complex soft $X$-ray spectrum dominated by emission lines of He and H-like transitions of elements from Carbon to Neon, as well as L-shell transitions due to…
We present a detailed study of X-ray absorption in the local interstellar medium by analyzing the X-ray spectra of 24 galactic sources obtained with the {\it Chandra} High Energy Transmission Grating Spectrometer and the {\it XMM-Newton}…
We analyzed a sample of 26 background X-ray sources in a ~60 square degree field of the Large Magellanic Cloud observed with the ROSAT PSPC. The sample has been selected from previously classified and optically identified X-ray sources. In…
The black hole binary Cygnus X-1 has a 5.6 day orbital period. We first detected a clear intensity modulation with the orbital period in its high/soft state with 6 year MAXI data, as well as in its low/hard state. In the low/hard state, the…
(abridged) We analyzed the archived XMM-Newton observation of the poorly studied low-mass X-ray binary XTE J1710-281 performed in 2004 that covered one orbital period of the system (3.8 hr). The source shows dips as well as eclipses, hence…
Aims. We present a 0.2--200 keV broad-band study of absorbed AGN observed with INTEGRAL, XMM-Newton, Chandra and ASCA to investigate the continuum shape and the absorbing/reflecting medium properties. Methods. The sources are selected in…