Related papers: X-ray Observations of the Hot Intergalactic Medium
Little is currently known about the physical properties of the hot circumgalactic medium (CGM) surrounding massive galaxies. Next-generation X-ray observatories will enable detailed studies of the hot CGM in emission. To support these…
We study the soft X-ray emission (0.1 - 1 keV) from the Warm-Hot Intergalactic Medium (WHIM) in a hydrodynamic simulation of a Cold Dark Matter universe. Our main goal is to investigate how such emission can be explored with a combination…
Surrounding the Milky Way (MW) is the circumgalactic medium (CGM), an extended reservoir of hot gas that has significant implications for the evolution of the MW. We used the HaloSat all-sky survey to study the CGM's soft X-ray emission in…
The abundances of gas and dust (solids and complex molecules) in the interstellar medium (ISM) as well as their composition and structures impact practically all of astrophysics. Fundamental processes from star formation to stellar winds to…
Gamma Ray Burst (GRB) afterglows close to their peak intensity are among the brightest X-ray sources in the sky. Despite their fast power-law like decay, when fluxes are integrated from minutes up to hours after the GRB event, the…
We investigate the 21-cm signature that may arise from the intergalactic medium (IGM) prior to the epoch of full reionization (z>5). In scenarios in which the IGM is reionized by discrete sources of photoionizing radiation, the neutral gas…
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…
In a previous paper, we calculated numerical hydrodynamic models of the interstellar medium in the Galaxy, which suggested that hot gas (T $\ge$ 3 $\times$ 10$^5$ K) has a filling factor near 50\% in the midplane (Rosen \& Bregman 1995, ApJ…
We estimate the heating of the intergalactic medium due to shocks arising from structure formation. Heating of the gas outside the collapsed regions, with small overdensities (${n_b \over {\bar n_b}}\ll 200$) is considered here, with the…
Cosmological simulations show that, at the present time, a substantial fraction of the gas in the intergalactic medium (IGM) has been shock-heated to T>10^5 K. Here we develop an analytic model to describe the fraction of shocked,…
Hot intergalactic gas in clusters, groups, and filaments emanates a continuous background of 0.5-2.0 keV X-rays that ought to be detectable with the new generation of X-ray observatories. Here we present selected results from a program to…
Galaxies are part of a vast cosmic ecosystem, embedded in an extensive gaseous reservoir that regulates their growth by providing the necessary fuel for star formation while preserving a fossil record of past interactions, outflows, and…
Galaxy groups host the majority of matter and more than half of all the galaxies in the Universe. Their hot ($10^7$ K), X-ray emitting intra-group medium (IGrM) reveals emission lines typical of many elements synthesized by stars and…
The hot, diffuse gas that fills the largest overdense structures in the Universe -- clusters of galaxies and a web of giant filaments connecting them -- provides us with tools to address a wide array of fundamental astrophysical and…
We present Chandra observations that provide the most direct evidence to date for the pervasive, moderate density, shock-heated intergalactic medium predicted by leading cosmological scenarios. We also comment briefly on future observations…
The lack of adequate X-ray observing capability is seriously impeding the progress in understanding the hot phase of circumgalactic medium (CGM), which is predicted to extend to the virial radius of a galaxy or beyond, and thus in acquiring…
We compute the expected X-ray diffuse background and radiative feedback on the intergalactic medium (IGM) from X-ray binaries prior and during the epoch of reionization. The cosmic evolution of compact binaries is followed using a…
Numerical simulations predict that a large number of baryons reside in intergalactic space at temperatures between 10^5-10^7 K. Highly-ionized metals, such as O VII and O VIII, are good tracers of this ``warm-hot intergalactic medium'', or…
The circumgalactic medium (CGM) is a vital element in galaxies, as it mediates the baryon cycle essential for regulating galaxy activity. It is also highly complex due to the intricate distributions of temperature, density, metallicity, and…
We point out that two problems of observational cosmology, the facts i) that > 60% of the baryonic content of the universe is not observed at z=0 and ii) that the properties of small clusters do not agree with simple expectations, could be…