Related papers: Intermediate evolution using SNIa, and BAO
We examine the possibility of evolution with redshift in the mean rest-frame ultraviolet (UV; <4500A) spectrum of Type Ia Supernovae (SNe Ia) sampling the redshift range 0<z<1.3. We find new evidence for a decrease with redshift in the…
We present the temporal evolution of line profiles ranging from near ultraviolet to optical wavelengths by analyzing 59 Subaru telescope spectra of normal Type Ia Supernovae (SNe Ia) in the intermediate redshift range (0.05 < z < 0.4)…
The rate evolution of subluminous Type Ia Supernovae is presented using data from the Supernova Legacy Survey. This sub-sample represents the faint and rapidly-declining light-curves of the observed supernova Ia (SN Ia) population here…
Based on detailed models for the explosions, light curves and NLTE-spectra, evolutionary effects of Type Ia Supernovae (SNe Ia) with redshift have been studied to evaluate their size on cosmological time scales,how the effects can be…
The $\Lambda$CDM model is the current standard model in cosmology thanks to its ability to reproduce the observations. Its first observational evidence appeared from the type Ia supernovae (SNIa) Hubble diagram. However, there has been some…
Despite the ability of the cosmological concordance model ($\Lambda$CDM) to describe the cosmological observations exceedingly well, power law expansion of the Universe scale radius, $R(t)\propto t^n$, has been proposed as an alternative…
Considering a quadratic parametrization of the dark energy density, we explore signatures of evolution using data from gas mass fraction in clusters, type Ia supernova, BAO and CMB. We find -- excluding CMB data -- a preference for a…
Late-time power law expansion has been proposed as an alternative to the standard cosmological model and shown to be consistent with some low-redshift data. We test power law expansion against the standard flat $\Lambda$CDM cosmology using…
In this work, we have proposed a general dark energy density parametrization to study the evolution of the universe. We have also constrained the model parameters using the combination of Type Ia supernova (SNIa), baryonic acoustic…
We revise observational constraints on the class of models of modified gravity which at low redshifts lead to a power-law cosmology. To this end we use available public data on Supernova Ia and on baryon acoustic oscillations. We show that…
The study of Type Ia supernovae (SNIa) has lead to greatly improved insights into many fields in astrophysics, however a theoretical explanation of the origin of these events is still lacking. We investigate the potential contribution to…
Observations of Type Ia supernovae (\sne), which probe the late Universe, together with baryon acoustic oscillations (BAO) and the cosmic microwave background (CMB), which probe the intermediate and early epochs, provide complementary…
The detailed nature of type Ia supernovae (SNe Ia) remains uncertain, and as survey statistics increase, the question of astrophysical systematic uncertainties arises, notably that of the evolution of SN Ia populations. We study the…
Observations of high-redshift Type Ia supernovae (SNe Ia) have provided strong evidence that the dark energy is real, and making further accurate observations of high-redshift SNe Ia is the most promising way to probe the nature of the dark…
We study characters of recent type Ia supernova (SNIa) data using evolving dark energy models with changing equation of state parameter w. We consider sudden-jump approximation of w for some chosen redshift spans with double transitions,…
We explore the possible role of evolution in the analysis of data on SNe Ia at cosmological distances. First, using a variety of simple sleuthing techniques, we find evidence that the properties of the high and low redshift SNe Ia observed…
Future measurements of the nature of dark energy using Type Ia supernovae will require a precise characterization of systematic sources of error. Evolutionary effects remain the most uncertain contributor to the overall systematic error…
Observations from Supernovae Type Ia (SNe Ia) provided strong evidence for an expanding accelerating Universe at intermediate redshifts. This means that the Universe underwent a transition from deceleration to acceleration phases at a…
We study intermediate--z SNe Ia using the empirical physical diagrams which enable to learn about those SNe explosions. This information can be very useful to reduce systematic uncertainties of the Hubble diagram of SNe Ia up to high z. The…
Type Ia supernovae (SNIa) play a central role in constraining the late-time expansion history of the Universe and are directly implicated in current cosmological tensions. Motivated by the possibility of unaccounted redshift-dependent…