Related papers: Can Dust Segregation Mimic a Cosmological Constant…
Condensation in the outer regions of decaying supernovae is an efficient source of dust with grain size up to 1 micron. The largest grains leave the parent galaxy, thus forming "grey" intergalactic dust, which can explain the observed…
Here we present some critical discussions about the systematic uncertainty by dust extinction in the recent cosmological results of high-redshift Type Ia supernovae. First we argue that the currently available data do not robustly exclude…
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 zero cosmological constant. In this Letter, I argue that bright,…
Using a high-resolution cosmological hydrodynamic simulation, we present a method to constrain extinction due to intergalactic grey dust based on the observed magnitudes of distant Type IA supernovae. We apply several simple prescriptions…
Scattering and absorption of light by a homogeneous distribution of intergalactic large dust grains has been proposed as an alternative, non-cosmological explanation for the faintness of Type Ia supernovae at $z\s im 0.5$. We investigate…
Extinction by intergalactic gray dust introduces a magnitude redshift dependent offset in the standard-candle relation of SN Ia. This leads to overestimated luminosity distances compared to a dust-free universe. Quantifying the amplitude of…
Distant supernovae have been observed to be fainter than what is expected in a matter dominated universe. The most likely explanation is that the universe is dominated by an energy component with negative pressure -- dark energy. However,…
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_solar < 1/3 for Omega_gas = 0.05. This metal density…
Measurements by dust detectors on interplanetary spacecraft appear to indicate a substantial flux of interstellar particles with masses exceeding 10^{-12}gram. The reported abundance of these massive grains cannot be typical of interstellar…
The observation of SN 1997ff at redshift 1.7 has been claimed to refute alternative models such as grey dust or evolution for the faintness of distant supernovae, leaving only an accelerating Universe as a viable model. However, a very…
Observations of high-redshift Type Ia supernovae (SNe~Ia) are used to study the cosmic transparency at optical wavelengths. Assuming a flat $\Lambda$CDM cosmological model based on BAO and CMB results, redshift dependent deviations of SN~Ia…
Distance estimates derived from spectroscopy or parallax have been unified by considering extinction by large grains. The addition of such a population of what is called Dark Dust to models of the diffuse interstellar medium is tested…
Unless properly corrected for, the existence of intergalactic dust will introduce a redshift dependent magnitude offset to standard candle sources. This would lead to overestimated luminosity distances compared to a dust-free universe and…
Extinction due to intergalactic grey dust has been proposed as an alternative to accelerated expansion to account for the dimming of \s fluxes beyond $z \simeq 0.5$. The ``replenishing'' grey dust model, although fitting the observational…
Observations have demonstrated that supernovae efficiently produce dust. This is consistent with the hypothesis that supernovae and asymptotic giant branch stars are the primary producers of dust in the Universe. However, there has been a…
Recent observations suggest appreciable star formation activity in early-type galaxies down to redshift $z\sim 0.5$. If so, there is likely to be dust in these galaxies. We consider the possibility that obscuration by dust can reconcile the…
To discriminate between different dust formation processes is a key issue in order to understand its properties. We analysed six submillimeter galaxies at redshifts 4<z<5 and nine quasars at 5<z<6.4. We estimated their dust masses from…
This chapter discusses Galactic dust and how its thermal emission confuses CMBR measurements. Interstellar dust grains are composed of many differing species, and observational evidence has only begun to disentagle their composition and…
Recent observations of Type Ia SNe at redshifts 0 < z <1 reveal a progressive dimming which has been interpreted as evidence for a cosmological constant of Omega_Lambda ~ 0.7. An alternative explanation of the SN results is an open universe…
Colour measurements of quasars are used to constrain the abundance and properties of intergalactic dust and the related extinction effects on high-z sources. For Type Ia supernovae at z = 1, we derive an upper limit on the possible dimming…