Related papers: Universe opacity and Type Ia supernova dimming
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…
Brighter Type Ia supernovae (SNe Ia) have broader, more slowly declining B-band light curves than dimmer SNe Ia. We study the physical origin of this width-luminosity relation (WLR) using detailed radiative transfer calculations of…
We studied the statistical properties of the luminosity distance and internal extinction data of type Ia supernovae in the lists published by Tonry et al. (2003) and Barris et al. (2004). After selecting the luminosity distance in an empty…
We analyze the influence of the evolution of light absorbtion by grey dust in SNe Ia host galaxies and the influence of the evolution of average total mass of coalescing double carbon-oxygen white dwarfs (progenitors of SNe Ia) under the…
We have discovered 16 Type Ia supernovae (SNe Ia) with the Hubble Space Telescope (HST) and have used them to provide the first conclusive evidence for cosmic deceleration that preceded the current epoch of cosmic acceleration. These…
The light curve of a distant Type Ia supernova acts like a clock that can be used to test the expansion of the Universe. SN~1995K, at a spectroscopic redshift of $z = 0.479$, provides one of the first meaningful data sets for this test. We…
The colour evolution of reddened Type Ia supernovae can place strong constraints on the location of dust and help address the question of whether the observed extinction stems from the interstellar medium or from circumstellar material…
Correctly interpreting observations of sources such as type Ia supernovae (SNe Ia) require knowledge of the power spectrum of matter on AU scales - which is very hard to model accurately. Because under-dense regions account for much of the…
Type Ia supernovae result when carbon-oxygen white dwarfs in binary systems accrete mass from companion stars, reach a critical mass, and explode. The near uniformity of their light curves makes these supernovae good standard candles for…
We investigate the potential of a future supernovae data set, as might be obtained by the proposed SNAP satellite, to discriminate between two possible explanations for the observed dimming of the high redshift type IA supernovae, namely…
Type Ia supernovae (SNe Ia) are useful distance indicators in cosmology, provided their luminosity is standardized by applying empirical corrections based on light-curve properties. One factor behind these corrections is dust extinction,…
We have made a quantitative calculation for the systematic evolution of average extinction by interstellar dust in host galaxies of high-redshift Type Ia supernovae, by using a realistic model of photometric and chemical evolution of…
Type Ia Supernovae (SNe Ia) are a critical tool in measuring the accelerating expansion of the universe. Recent efforts to improve these standard candles have focused on incorporating the effects of dust on distance measurements with SNe…
We analyze the magnitude-redshift data of type Ia supernovae included in the Union and Union2 compilations in the framework of an anisotropic Bianchi type I cosmological model and in the presence of a dark energy fluid with anisotropic…
Type Ia supernovae (SNe Ia) currently provide the most direct evidence for an accelerating Universe and for the existence of an unknown "dark energy" driving this expansion. The 5-year Supernova Legacy Survey (SNLS;…
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…
We present UBVRIJHK photometry and optical spectroscopy of the so-called 'peculiar' Type Ia supernova 1999by in NGC 2841. The observations began one week before visual maximum light which is well-defined by daily observations. The light…
Type Ia supernova (SNIa) are excellent probes of local distance, and the increasing sample sizes of SNIa have driven an increased need to study the associated systematic uncertainties and improve the standardisation methods in preparation…
We study the properties of low-velocity material in the line of sight towards nearby Type Ia Supernovae (SNe Ia) that have measured late phase nebular velocity shifts (v_neb), thought to be an environment-independent observable. We have…
The $m$-$z$ relation for Type Ia supernovae is compatible with the cosmological concordance model if one assumes that the Universe is homogeneous, at least with respect to light propagation. This could be due to the density along each line…