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METALLICITY OF THE INTERGALACTIC MEDIUM USING PIXEL STATISTICS. II. THE DISTRIBUTION OF METALS AS TRACED BY C IV
We measure the distribution of carbon in the intergalactic medium as a function of redshift z and overdensity δ. Using a hydrodynamical simulation to link the H I absorption to the density and
Intergalactic Dust and Observations of Type Ia Supernovae
Estimates of the cosmic star formation rate and of cluster metallicities independently imply that at z 0.5 the gas in the universe has substantial average metallicity: 1/10 Z/Z☉ 1/3 for Ωgas = 0.05.
The missing metals problem – III. How many metals are expelled from galaxies?
We revisit the metal budget at z ≃ 2, and include the contribution of the intergalactic medium (IGM). Past estimates of the metal budget have indicated that, at redshift z ≃ 2.5, 90 per cent of the
Dimensionless constants, cosmology and other dark matters
We identify 31 dimensionless physical constants required by particle physics and cosmology, and emphasize that both microphysical constraints and selection effects might help elucidate their origin.
Metal Enrichment of the Intergalactic Medium in Cosmological Simulations
Observations have established that the diffuse intergalactic medium (IGM) at z ~ 3 is enriched to ~10-2.5 solar metallicity and that the hot gas in large clusters of galaxies (ICM) is enriched to -
Dust versus Cosmic Acceleration
Two groups have recently discovered a statistically significant deviation in the fluxes of high-redshift Type Ia supernovae from the predictions of a Friedmann model with a zero cosmological
Cosmological Constant or Intergalactic Dust? Constraints from the Cosmic Far-Infrared Background
Recent observations of Type Ia supernovae (SNe) at redshifts 0 < z < 1 reveal a progressive dimming that has been interpreted as evidence for a cosmological constant of ΩΛ ~ 0.7. An alternative
Metal enrichment of the intergalactic medium at z=3 by galactic winds
Studies of quasar absorption lines reveal that the low-density intergalactic medium (IGM) at z ~ 3 is enriched to between 10-3 and 10-2 solar metallicity. This enrichment may have occurred in an
Dark matter capture in the first stars: a power source and limit on stellar mass
The annihilation of weakly interacting massive particles can provide an important heat source for the first (Pop III, 'Pop' standing for 'population') stars, potentially leading to a new phase of
Information Transmission between Financial Markets in Chicago and New York
High-frequency trading has led to widespread efforts to reduce information propagation delays between physically distant exchanges. Using relativistically correct millisecond-resolution tick data, we
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