Related papers: The hot interstellar medium towards 4U 1820-30: a …

A search for O VI at redshifts corresponding to Ly-alpha lines in the z_em ~ 2.4 QSOs HE1122-1648 and HE2217-2818 reveals that a substantial fraction of those with H I column densities log N(HI) > 14 (cm^{-2}) are highly ionized and show…

Several popular cosmological models predict that most of the baryonic mass in the local universe is located in filamentary and sheet-like structures associated with galaxy overdensities. This gas is expected to be gravitationally heated to…

Recent STIS and FUSE observations have detected OVI absorption lines at low redshift that are not clearly associated with any galactic system. In this paper, we argue that these lines are due to metal enriched hot gas in the intergalactic…

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…

We show that the Fe XVII I(17.10 A)/I(17.05 A) line ratio observed in the Chandra HETG spectrum of the intermediate polar EX Hydrae is significantly smaller than that observed in the Sun or other late-type stars. Using the Livermore X-ray…

We test the X-ray emission predictions of galactic fountain models against XMM-Newton measurements of the emission from the Milky Way's hot halo. These measurements are from 110 sight lines, spanning the full range of Galactic longitudes.…

We report a study of the H30$\alpha$ line emission at 1.3 mm from the region around Sgr A* made with the Submillimeter Array at a resolution of 2\arcsec\ over a field of 60\arcsec\ (2 parsec) and a velocity range of -360 to +345 \kms. This…

We propose a methodology to perform a self-consistent analysis of the physical properties of the emitting gas of HII galaxies adequate to the data that can be obtained with the XXI century technology. This methodology requires the…

The extremely faint, temperature sensitive ``auroral'' emission line [N II] 5755 has been detected from the low density ionized gas along the sight line toward l = 130.0, b = -7.5 using the Wisconsin H-Alpha Mapper (WHAM). The intensity of…

Observations of the "Warm Ionized Medium" (or, equivalently, the "Diffuse Ionized Gas") of the local ISM, the Perseus arm in the Milky Way, and also in several other galaxies show strong [NII]6563 (~H-alpha in some cases) and…

We present measurements of the Galactic halo's X-ray emission for 110 XMM-Newton sight lines, selected to minimize contamination from solar wind charge exchange emission. We detect emission from few million degree gas on ~4/5 of our sight…

We report on an XMM-Newton observation of the ultraluminous infrared galaxy NGC 6240. The 0.3-10 keV spectrum can be successfully modelled with: (i) three collisionally ionized plasma components with temperatures of about 0.7, 1.4, and 5.5…

{We explored the {softness parameter} in the infrared, whose main purpose is the characterisation of the hardness of the incident ionising radiation in emission-line nebulae. This parameter is obtained from the combination of mid-infrared…

The analysis of the third INTEGRAL/IBIS survey has revealed several new cataclysmic variables, most of which turned out to be intermediate polars, thus confirming that these objects are strong emitters in hard X-rays. Here we present high…

The properties of the warm-hot intergalactic medium (WHIM) in cosmic filaments are among the least quantified units in modern astrophysics. The Spectrum Roentgen Gamma/eROSITA All Sky Survey ((SRG/eRASS) provides a unique opportunity to…

Aims: We systematically explore a plausible subset of the parameter space involving effective temperatures and metallicities of the ionizing stellar sources, the effects of the hardening of their radiation by surrounding leaky HII regions…

Results of the spectral analysis for the galaxy cluster IGR J17448-3232 are presented. The intracluster medium (ICM) in the central region (r<300", 320 kpc) has a high electron temperature plasma of kTe~13-15 keV and an ionization…

We investigate properties of the interstellar medium (ISM) in galaxies hosting long-duration gamma-ray bursts (GRBs) from an analysis of atomic species (MgI, FeI) and excited fine-structure levels of ions (e.g. SiII). Our analysis is guided…

We propose observations of the molecular gas distribution during the era of reionization. At $z \sim $ 6 to 8, $^{12}$CO$(J=1-0)$ line intensity results in a mean brightness temperature of about 0.5 $\mu$K with rms fluctuations of 0.1…

SS73 17 was an innocuous Mira-type symbiotic star until Integral and Swift discovered its bright hard X-ray emission, adding it to the small class of "hard X-ray emitting symbiotics." Suzaku observations in 2006 then showed it emits three…