Related papers: Does Amati Relation Depend on Luminosity of GRB's …
Gamma-ray bursts (GRBs) are widely proposed as an effective probe to trace the Hubble diagram of the Universe in high redshift range. However, the calibration of GRBs is not as easy as that of type-Ia supernovae (SNe Ia). Most calibrating…
Long-duration gamma-ray bursts (GRBs) provide a premier tool for studying high-redshift star-forming galaxies thanks to their extreme brightness and association with massive stars. Here we use GRBs to study the galaxy mass-metallicity…
The recently-discovered Fundamental Metallicity Relation (FMR), which is the tight dependence of metallicity on both mass and SFR, proves to be a very useful tool to study the metallicity properties of various classes of galaxies. We have…
By dividing a sample of 48 long-duration gamma-ray bursts (GRBs) into four groups with redshift from low to high and fitting each group with the Amati relation log Eiso = a + b log Epeak, I find that parameters a and b vary with the mean…
We present optical and near-IR observations of the host galaxy of GRB 020127, for which we measure R-K=6.2 mag. This is only the second GRB host to date, which is classified as an ERO. The spectral energy distribution is typical of a dusty…
Gamma-ray bursts (GRBs) are extremely powerful stellar explosions that have been observed to huge distances with redshifts exceeding 9. Although GRBs are not standard candles, one may standardize them by calibrating certain correlations…
The well-known hardness-duration correlation of gamma-ray bursts (GRBs) is investigated with the data of the 4B catalog. We find that, while the hardness ratio and the duration are obviously correlated for the entire set of the 4B catalog,…
We analyze a sample of 16 absorption systems intrinsic to long duration GRB host galaxies at $z \gtrsim 2$ for which the metallicities are known. We compare the relation between the metallicity and cold gas velocity width for this sample to…
We investigate the nature of the mass-metallicity (M-Z) relation for long gamma-ray burst (LGRB) host galaxies. Recent studies suggest that the M-Z relation for local LGRB host galaxies may be systematically offset towards lower…
With optical and near-infrared follow-up observations of gamma-ray bursts (GRBs) it is possible to study the chemical enrichment of galaxies at high redshift. Especially interesting are measurements of the metallicity of GRB host with…
We use a sample of \textit{Swift} gamma-ray bursts (GRBs) to analyze the Amati and Yonetoku correlations. The first relation is between $E_{p,i}$, the intrinsic peak energy of the prompt GRB emission, and $E_{iso}$, the equivalent isotropic…
We present spectroscopic observations of the host galaxy and explosion site of the long-duration gamma-ray burst GRB 020819. We determine a metallicity for this host environment of log(O/H) + 12 = 9.0 +/- 0.1, by far the highest metallicity…
Gamma-ray bursts (GRBs) are promising cosmological probes for exploring the Universe at intermediate redshifts ($z$). We analyze 151 Fermi-observed long GRBs (datasets A123 and A28) to simultaneously constrain the Amati correlation and…
The association of some short-duration gamma-ray bursts (GRBs) with elliptical galaxies established that their progenitors, unlike those of long GRBs, belong to an old stellar population. However, the majority of short GRBs appear to occur…
We discuss the host galaxy metallicity distribution of all long gamma-ray bursts (GRBs) whose redshifts are known to be $< 0.4$, including newly obtained spectroscopic datasets of the host galaxies of GRB 060614, 090417B, and 130427A. We…
We have conducted the first dedicated spectroscopic survey of long-duration gamma-ray burst (LGRB) host galaxies at z < 1, and use these observations along with data from the literature to determine a wide range of ISM properties and a…
Models of chemical enrichment and inhomogeneity in high-redshift galaxies are challenging to constrain observationally. In this work, we discuss a novel approach to probe chemical inhomogeneities within long Gamma-Ray Burst (GRB) host…
Aims. We have gathered optical spectra of 8 long-duration GRB host galaxies selected from the archival data of VLT/FORS2. We investigated whether or not Wolf-Rayet (WR) stars can be detected in these GRB host galaxies. We also tried to…
Long gamma-ray bursts (GRBs) have been suggested to occur preferentially in low metallicity environment. We discuss the possibility and theoretical aspects of using Lyman alpha emission properties of long GRB host galaxies as a metallicity…
The correlation between the peak photon energy of the internal spectrum Ep,i and isotropic equivalent radiated energy Eiso (the Amati relation) is explored in a scalar field model of dark energy. Using an updated data set of 109 high…