相关论文: Hydrodynamic Simulation of the Cosmological X-ray …
The energy density of the Cosmic X-ray background (XRB) peaks around 30 keV (see Figure 1), an energy not yet probed by focussing imaging instruments. The first hard X-ray telescope due to fly on a space mission will be that on board…
Radio observations of galaxy clusters show that there are $\mu$G magnetic fields permeating the intra-cluster medium (ICM), but it is hard to accurately constrain the strength and structure of the magnetic fields without the help of…
The shocks produced in the intergalactic medium during large-scale structure formation accelerate a population of highly relativistic electrons which emit synchrotron radiation due to intergalactic magnetic fields. In a previous paper (Loeb…
X-ray emission can provide a crucial diagnostic of gamma-ray bursts (GRBs). We calculate the X-ray and gamma-ray spectra of impulsive acceleration episodes related to GRB pulses. We use the synchrotron shock model (SSM) as a basis of our…
We analyze the properties of a sample of long gamma-ray bursts (LGRBs) detected by the Fermi satellite that have a spectroscopic redshift and good follow-up coverage at both X-ray and optical/nIR wavelengths. The evolution of LGRB…
The hot circumgalactic medium (CGM), probed by X-ray observations, plays a central role in understanding gas flows that drive a galaxy's evolution. While CGM properties have been widely studied, the influence of a galaxy's large-scale…
The Hydra I galaxy cluster (Abell 1060) is a nearby example of a low-temperature cluster that exhibits intermediate cool core and non-cool core properties. We aim to extend the characterization of the intracluster medium (ICM) properties at…
The isotropic diffuse $\gamma$-ray background (IGRB) has been detected by various experiments and recently the Fermi-LAT Collaboration has precisely measured its spectrum in a wide energy range. The origin of the IGRB is still unclear and…
We decompose the COBE/DIRBE observations of the near-IR sky brightness (minus zodiacal light) into Galactic stellar and interstellar medium (ISM) components and an extragalactic background. This empirical procedure allows us to estimate the…
We have analyzed the soft X-ray emission in a wide area of the Sculptor supercluster by using overlapping ROSAT PSPC pointings. After subtraction of the point sources we have found evidence for extended, diffuse soft X-ray emission. We have…
We examine the scalings of X-ray luminosity, temperature, and dark matter or galaxy velocity dispersion for galaxy groups in an LCDM cosmological simulation, which incorporates gravity, gas dynamics, radiative cooling, and star formation,…
X-ray selected samples are known to miss galaxy clusters that are gas poor and have a low surface brightness. This is different for the optically selected samples such as the X-ray Unbiased Selected Sample (XUCS). We characterise the origin…
Transport properties, such as viscosity and thermal conduction, of the hot intergalactic plasma in clusters of galaxies, are largely unknown. While for laboratory plasmas these characteristics are derived from the gas density and…
The X-ray emission properties from the hot thermalized plasma that results from the collisions of individual stellar winds and supernovae ejecta within rich and compact star clusters are discussed. We propose a simple analytical way of…
We have carried out 2D hydrodynamical simulations in order to study the interaction between supernova-powered gas outflows from low-mass galaxies and the local intergalactic medium (IGM). We are specifically interested in investigating…
The Universe has evolved from an initial diffuse, uniform gas to a complex structure that includes both voids and high-density galaxy clusters connected by gaseous filaments, known as the Cosmic Web, and traced by 3D surveys of galaxies.…
We study the $z\approx3.5$ intergalactic medium (IGM) by comparing new, high-quality absorption spectra of eight QSOs with $\langle z_{\rm QSO} \rangle=3.75$, to virtual observations of the EAGLE cosmological hydrodynamical simulations. We…
The Galactic centre is a hotbed of astrophysical activity, with the injection of wind material from $\sim$30 massive Wolf-Rayet (WR) stars orbiting within 12" of the super-massive black hole (SMBH) playing an important role. Hydrodynamic…
Recent high resolution observations by the {\it Chandra} X-ray satellite revealed various substructures in hot X-ray emitting plasmas in cluster of galaxies. For example, {\it Chandra} revealed the existence of sharp discontinuities in the…
The origin of the diffuse gamma-ray background (DGRB), the one that remains after subtracting all individual sources from observed gamma-ray sky, is unknown. The DGRB possibly encompasses contributions from different source populations such…