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Related papers: Probing cosmological parameters with GRBs

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We discuss the prospects of using Gamma Ray Bursts (GRBs) as high-redshift distance estimators, and consider their use in the study of two dark energy models, the Generalized Chaplygin Gas (GCG), a model for the unification of dark energy…

Astrophysics · Physics 2007-05-23 O. Bertolami P. T. Silva

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…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 V. F. Cardone , M. G. Dainotti , S. Capozziello , R. Willingale

Gamma ray bursts (GRBs) are short and intense pulses of $\gamma$-rays arriving from random directions in the sky. Several years ago Amelino-Camelia et al. pointed out that a comparison of time of arrival of photons at different energies…

Astrophysics · Physics 2009-11-10 Tsvi Piran

We present precise constraints on the normalization of the power spectrum of mass fluctuations in the nearby universe, sigma_8, as a function of the mean local matter density, Omega_m. Using the observed local X-ray luminosity function of…

Astrophysics · Physics 2008-11-26 S. W. Allen , R. W. Schmidt , A. C. Fabian , H. Ebeling

In this paper, the effect of the intrinsic distribution of cosmological candles is investigated. We find that, in the case of a narrow distribution, the deviation of the observed modulus of sources from the expected central value could be…

We present the constraints on the cosmological parameters obtained with the $E_{\rm peak}$--$E_{\gamma}$ correlation found with the most recent sample of 19 GRBs with spectroscopically measured redshift and well determined prompt emission…

Astrophysics · Physics 2009-11-11 G. Ghirlanda , G. Ghisellini , C. Firmani , L. Nava , F. Tavecchio , D. Lazzati

We present a study of the baryonic fraction in galaxy clusters aimed at constraining the cosmological parameters Omega_m, Omega_Lambda and the ratio between the pressure and density of the ``dark'' energy, w. We use results on the…

Astrophysics · Physics 2008-11-26 S. Ettori , P. Tozzi , P. Rosati

A sample of 20 powerful extended radio galaxies with redshifts between zero and two were used to determine constraints on global cosmological parameters. Data for six radio sources were obtained from the VLA archive, analyzed, and combined…

Astrophysics · Physics 2015-06-24 Erick J. Guerra , Ruth A. Daly , Lin Wan

One of the most important discoveries in the observation of gamma-ray bursts (GRBs) is that the total energy emitted by a GRB in gamma-rays has a very narrow distribution around 10^51 erg, which has led people to claim that GRBs are…

Astrophysics · Physics 2008-07-16 Li-Xin Li

Galactic Gamma-Ray Bursts (GRBs) are copious sources of gamma-rays that can pose a threat to complex life. Using recent determinations of their rate and the probability of GRBs causing massive extinction, we explore what type of universes…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-02 Tsvi Piran , Raul Jimenez , Antonio J. Cuesta , Fergus Simpson , Licia Verde

Millilensing of Gamma-Ray Bursts (GRBs) is expected to manifest as multiple emission episodes in a single triggered GRB with similar light-curve patterns and similar spectrum properties. Identifying such lensed GRBs could help improve…

High Energy Astrophysical Phenomena · Physics 2022-05-25 Shi-Jie Lin , An Li , He Gao , Lin Lin , Bin-Bin Zhang , Zi-Ke Liu , Jin-Hang Zou , Zhao Zhang , Huan Zhou , Zheng-Xiang Li , Lin Lan

Fermi satellite discovered that cosmological gamma-ray bursts (GRBs) are accompanied by long GeV flashes. In two GRBs, an optical counterpart of the GeV flash has been detected. Recent work suggests that the GeV+optical flash is emitted by…

High Energy Astrophysical Phenomena · Physics 2015-11-04 Romain Hascoët , Indrek Vurm , Andrei M. Beloborodov

Probing the evolution of the universe at high redshifts with standard candles is a powerful way to discriminate dark energy models, where an open question nowadays is whether this component is constant or evolves with time. One possible…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-01 R. F. L. Holanda , V. C. Busti

An $E_{\gamma,{\rm jet}}\propto {E'_p}^{1.5}$ relationship with a small scatter for current $\gamma$-ray burst (GRB) data was recently reported, where $E_{\gamma,{\rm jet}}$ is the beaming-corrected $\gamma$-ray energy and $E'_p$ is the…

Astrophysics · Physics 2016-08-30 Z. G. Dai , E. W. Liang , D. Xu

We have identified seven (field) elliptical galaxies acting as strong gravitational lenses and have used them to measure cosmological parameters. To find the most likely value for Omega_m (= Omega_matter) and Lambda, we have used the…

Astrophysics · Physics 2009-10-28 Myungshin Im , Richard E. Griffiths , Kavan U. Ratnatunga

Fourteen classical double radio galaxies with redshifts between zero and two were used to determine the cosmological parameters $\Omega_m$, $\Omega_{\Lambda}$, and $\Omega_k$, where these are the normalized values of the mean mass density,…

Astrophysics · Physics 2007-05-23 Ruth A. Daly , E. J. Guerra , Lin Wan

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,…

High Energy Astrophysical Phenomena · Physics 2016-02-17 Patrick Petitjean , F. Y. Wang , X. F. Wu , J. J. Wei

Several correlations among Gamma-Ray Bursts (GRBs) quantities, both in the prompt and afterglow emissions, have been established during the last decades, thus enabling the standardization of GRBs as cosmological probes. Since GRBs are…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-29 Giada Bargiacchi , Maria Giovanna Dainotti , Salvatore Capozziello

With the understanding that the enigmatic Gamma-Ray Burts (GRBs) are beamed explosions, and with the recently discovered ``Ghirlanda-relation'', the dream of using GRBs as cosmological yardsticks may have come a few steps closer to reality.…

Astrophysics · Physics 2009-07-29 E. Mortsell , J. Sollerman

Ground based extensive air showers arrays can observe GRBs in the 1-1000 GeV energy range using the "single particle" techique. The sensitivity to detect a GRB as a function of the burst parameters and the detector characteristics are…

Astrophysics · Physics 2011-05-23 Silvia Vernetto
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