相关论文: Effect of the Metallicity on the X-ray Emission fr…
We investigate the metallicity evolution and content of the intergalactic medium (IGM) and galactic halo gas from z=2->0 using 110-million particle cosmological hydrodynamic simulations. We focus on the detectability and physical properties…
The relevance of some galactic feedback mechanisms, in particular cosmic ray feedback and the hydrogen ionizing radiation field, has been challenging to definitively describe in a galactic context, especially far outside the galaxy in the…
We measured the oxygen abundances of the warm (T$\sim 10^{4}K$) phase of gas in seven early-type galaxies through long-slit observations. A template spectra was constructed from galaxies void of warm gas and subtracted from the…
We present $[OIII]/H_{\rm \beta}$ emision line flux ratio predictions for galaxies at $z \sim 7-9$ using the MAPPINGS V v5.2.0 photoionization modelling code combined with an analytic galaxy formation model. Properties such as pressure and…
We use the observed number and column-density distributions of intergalactic O VI absorbers to constrain the distribution of metals in the low-redshift intergalactic medium (IGM). In this simple model the metals in the O VI absorbers are…
We study the properties of the circumgalactic medium (CGM) of high-$z$ galaxies in the metal enrichment simulations presented in Pallottini et al. 2014. At $z=4$, we find that the simulated CGM gas density profiles are self-similar, once…
The circumgalactic medium (CGM) of nearby star-forming galaxies show clear indications of \ion{O}{6} absorption accompanied by little to no \ion{N}{5} absorption. This unusual spectral signature, accompanied by absorption from lower…
In the Halo21 absorption modeling challenge we generated synthetic absorption spectra of the circumgalactic medium (CGM), and attempted to estimate the metallicity, temperature, and density (Z, T, and nH) of the underlying gas using…
Measurements of the intergalactic medium (IGM) temperature provide a potentially powerful constraint on the reionisation history due to the thermal imprint left by the photo-ionisation of neutral hydrogen. However, until recently IGM…
We study the column densities of neutral atomic, molecular, and warm ionized Galactic gas through their continuous absorption of extragalactic X-ray spectra at |b| > 25 degrees. For N(H,21cm) < 5x10^20 cm^-2 there is an extremely tight…
We present an analysis of mock spectral observation of warm-hot intergalactic medium (WHIM) using a constrained simulation of the local universe. The simulated map of oxygen emission lines from local WHIM reproduces well the observed…
We study the ionization and thermal evolution of the intergalactic medium during the epoch of \heii reionization by means of radiation hydrodynamical cosmological simulations. We post-process baryonic density fields from a standard…
A simple analytical model is used to calculate the X-ray heating of the IGM for a range of black hole masses. This process is efficient enough to decouple the spin temperature of the intergalactic medium from the cosmic microwave background…
We present constraints on both the kinetic temperature of the intergalactic medium (IGM) at z=8.4, and on models for heating the IGM at high-redshift with X-ray emission from the first collapsed objects. These constraints are derived using…
The Wisconsin H-Alpha Mapper (WHAM) is a high throughput Fabry-Perot facility developed specifically to detect and explore the warm, ionized component of the interstellar medium at high spectral resolution. It began operating at Kitt Peak,…
Understanding the sources responsible for reionizing the Universe is a key goal of observational cosmology. A discrepancy has existed between the metagalactic hydrogen ionization rate, Gamma_HI, predicted by early hydrodynamical simulations…
The ultraviolet background (UVB) emitted by quasars and galaxies governs the ionization and thermal state of the intergalactic medium (IGM), regulates the formation of high-redshift galaxies, and is thus a key quantity for modeling cosmic…
The Interstellar Medium (ISM) comprises gases at different temperatures and densities, including ionized, atomic, molecular species, and dust particles. The neutral ISM is dominated by neutral hydrogen and has ionization fractions up to 8%.…
We present new measurements of the intensity of the ionizing ultraviolet background and the global emissivity of ionizing photons over 2 < z < 5. Our results are based on a suite of updated measurements of physical properties of the…
In our current galaxy formation paradigm, high-redshift galaxies are predominantly fuelled by accretion of cool, metal-poor gas from the intergalactic medium. Hydrodynamical simulations predict that this material should be observable in…