Related papers: X-ray Absorption Lines in the Warm-Hot Intergalact…
This paper presents constraints on the cosmological density of baryons from a systematic search for O VII and O VIII absorption lines in the XMM-Newton and Chandra X-ray spectra of 51 background sources. The search is based on far…
The Warm-Hot Intergalactic Medium (WHIM) is believed to host a significant fraction of the ``missing baryons'' in the nearby Universe. Its signature has been detected in the X-ray absorption spectra of distant quasars. However, its…
Based on constraints from Big Bang nucleosynthesis and the cosmic microwave background, the baryon content of the high-redshift Universe can be precisely determined. However, at low redshift, about one-third of the baryons remain…
The circumgalactic medium (CGM) around galaxies is believed to record various forms of galaxy feedback and contain a significant portion of the "missing baryons" of individual dark matter halos. However, clear observational evidence for the…
The warm-hot intergalactic medium (WHIM) at temperatures 1E5-1E7 K is believed to contain 30-50% of the baryons in the local universe. However, all current X-ray detections of the WHIM at redshifts z>0 are of low statistical significance…
The current observational status of the hot (log T(K) > 5.5) warm-hot intergalactic medium (WHIM) remains incomplete. While recent observations from stacking large numbers of Cosmic Web filaments have yielded statistically significant…
It has been known for decades that the observed number of baryons in the local universe falls about 30-40% short of the total number of baryons predicted by Big-Bang Nucleosynthesis, as inferred from density fluctuations of the Cosmic…
Most of cosmic baryons predicted by the big-bang nucleosynthesis has evaded the direct detection. Recent numerical simulations indicate that approximately 30 to 50 percent of the total baryons in the present universe is supposed to take a…
This paper presents an analysis of XMM X--ray spectra of the quasar 1ES 1553+113, in search for absorption lines from the intervening warm--hot intergalactic medium. A search for OVII, OVIII and NeIX resonance absorption lines was performed…
The problem of missing baryons in the local universe remains an open question. One propose alternative is that at low redshift missing baryons are in the form of the Warm Hot Intergalactic Medium (WHIM). In order to test this idea, we…
In this contribution, I review the current observational evidence for the existence of filaments of Warm-Hot Intergalactic Medium (WHIM). In particular, I first focus on the controversial issue of the identification of the $z\sim 0$ highly…
The "missing baryons", in the form of warm-hot intergalactic medium (WHIM), are expected to reside in cosmic filamentary structures that can be traced by signposts such as large-scale galaxy superstructures. The clear detection of an X-ray…
This paper presents initial results of a systematic search for resonance X-ray absorption lines from H-like O VIII and He-like O VII caused by the intervening warm-hot intergalactic medium (WHIM). The search is based on far ultra-violet…
Context. Hydrodynamical cosmological simulations based on the $\Lambda$-Cold Dark Matter ($\Lambda$CDM) model predict that $\sim$40% of the baryons in the local Universe are missing. These missing baryons are predicted to lie in low-density…
The amount of baryons hosted in the disks of galaxies is lower than expected based on the mass of their dark-matter halos and the fraction of baryon-to-total matter in the universe, giving rise to the so called galaxy missing-baryon…
Many of the baryons associated with a galaxy reside in its circumgalactic medium (CGM), in a diffuse volume-filling phase at roughly the virial temperature. Much of the oxygen produced over cosmic time by the galaxy's stars also ends up…
Recent ultraviolet and X-ray observations of intergalactic OVI and OVII absorption systems along lines of sight to bright quasars have opened a new window onto the ``warm-hot intergalactic medium'' (WHIM). These systems appear to provide a…
Numerical simulations of the intergalactic medium have shown that at the present epoch a significant fraction (40-50%) of the baryonic component should be found in the (T~10^6K) Warm-Hot Intergalactic Medium (WHIM) - with several recent…
Hydrodynamic simulations of growth of cosmic structure suggest that 30-50% of the total baryons at z=0 may be in a warm-hot intergalactic medium (WHIM) with temperatures ~10^5-10^7K. The O VI \lambda \lambda 1032, 1038 absorption line…
At low redshift (z<2), almost half of the baryons in the Universe are not found in bound structures like galaxies and clusters and therefore most likely reside in a Warm-Hot Intergalactic Medium (WHIM), as predicted by simulations. Attempts…