Related papers: Study of possible systematics in the L*X - Ta* cor…
Gamma-ray bursts (GRBs) are short and intense flashes at the cosmological distances, which are the most luminous explosions in the Universe. The high luminosities of GRBs make them detectable out to the edge of the visible universe. So,…
Gamma-Ray Bursts (GRBs) are fascinating events due to their panchromatic nature. Their afterglow emission is observed from sub-TeV energies to radio wavelengths. We investigate GRBs that present an optical plateau, leveraging on the…
Two different luminosity indicators have recently been proposed for Gamma Ray Bursts that use gamma-ray observations alone. They relate the burst luminosity (L) with the time lag between peaks in hard and soft energies, and the spikiness or…
We present the statistical analysis of the properties of gamma-ray bursts with measured host galaxy redshifts and peaked optical light curves in proper frames of reference. The optical transients are classified by comparing the time lag of…
Gamma-Ray Bursts (GRBs) are the most violent explosions in the Universe. Long duration GRBs are associated with the collapse of massive stars, rivaling their host galaxies in luminosity. The discovery of the most distant spectroscopically…
We present the Hubble diagram (HD) of 66 Gamma Ray Bursts (GRBs) derived using only data from their X - ray afterglow lightcurve. To this end, we use the recently updated L_X - T_a correlation between the break time T_a and the X - ray…
Due to their highly luminous nature, gamma-ray bursts (GRBs) are useful tools in studying the early Universe (up to z = 10). We consider whether the available subset of Swift high redshift GRBs are unusual when compared to analogous…
The variable activity of a gamma-ray burst (GRB) source is thought to be correlated with its absolute peak luminosity - a relation that, if confirmed, can be used to derive an independent estimate of the redshift of a GRB. We find that…
To reveal and understand astrophysical processes responsible for the Gamma Ray Burst (GRB) phenomenon, it is crucial to discover and understand relations between their observational properties. The presented study is performed in the GRB…
Gamma-ray bursts (GRBs) are traditionally classified into long (lGRBs) and short (sGRBs) durations based on their $T_{90}$, with lGRBs widely used as tracers of the cosmic star formation rate (SFR) due to their observed association with…
The origin of prompt emission from gamma ray bursts remains to be an open question. Correlated prompt optical and gamma-ray emission observed in a handful of GRBs strongly suggests a common emission region, but failure to adequately fit the…
Starting from the Swift sample we define a complete sub-sample of 58 bright long Gamma Ray Bursts (GRB), 55 of them (95%) with a redshift determination, in order to characterize their properties. Our sample (BAT6) allows us to study the…
Gamma-ray bursts (GRBs) can be probes of the early universe, but currently, only 26% of GRBs observed by the Neil Gehrels Swift Observatory GRBs have known redshifts ($z$) due to observational limitations. To address this, we estimated the…
The Gamma-Ray Bursts - GRBs are one of the most energetic astronomical events in the universe that have not yet an adequate explanation of what kind of mechanism is carried out. This question motivates the astronomical community to do…
The present common view about GRB origin is related to cosmology, what is based on statistical analysis, and on measurements of the redshifts in the GRB optical afterglows of long GRB. No correlation is found between redshifts, GRB…
We use the correlation relation between the energy emitted by the GRBs in their prompt phases and the X-ray afterglow fluxes, in an effort to constrain cosmological parameters and aiming to construct a Hubble diagram at high redshifts, i.e.…
The use of Gamma Ray Bursts as ``standard candles'' has been made possible by the recent discovery of a very tight correlation between their rest frame intrinsic properties. This correlation relates the GRB prompt emission peak spectral…
Gamma-ray bursts (GRBs), which have been observed up to redshifts z approx 9.5 can be good probes of the early universe and have the potential of testing cosmological models. The analysis by Dainotti of GRB Swift afterglow lightcurves with…
The present common view about GRB origin is related to cosmology. There are two evidences in favour of this interpretation. The first is connected with statistics, the second is based on measurements of the redshifts in the GRB optical…
The determination of distances is highly constrained to a small number of Gamma-Ray Bursts (GRBs) because it requires observations at different wavelengths. Some empirical functions to estimate redshifts have been identified using…