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Model-independent bounds on the Hubble constant $H_0$ are important to shed light on cosmological tensions. We work out a model-independent analysis based on the sum rule, which is applied to late- and early-time data catalogs to determine…

Cosmology and Nongalactic Astrophysics · Physics 2025-09-17 Orlando Luongo , Marco Muccino

Gamma-Ray Bursts (GRBs) are interesting objects for testing the emission models in highly energetic regimes and are very promising standardizable candles, given their observability at high redshift (up to $z=9.4$) that allows the extension…

High Energy Astrophysical Phenomena · Physics 2023-11-28 Maria Giovanna Dainotti , Biagio De Simone

Most diffuse baryons, including the circumgalactic medium (CGM) surrounding galaxies and the intergalactic medium (IGM) in the cosmic web, remain unmeasured and unconstrained. Fast Radio Bursts (FRBs) offer an unparalleled method to measure…

In this paper, we perform a cosmological model-independent test of the cosmic distance-duality relation (CDDR) in terms of the ratio of angular diameter distance (ADD) $D=D_{\rm A}^{\rm sl}/D_{\rm A}^{\,\rm s}$ from strong gravitational…

General Relativity and Quantum Cosmology · Physics 2017-07-26 Xiangyun Fu , Pengcheng Li

The correlation between the peak spectra energy ($E_p$) and the equivalent isotropic energy ($E_{\rm iso}$) of long gamma-ray bursts (GRBs), the so-called Amati relation, is often used to constrain the high-redshift Hubble diagram. Assuming…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-16 Lu Huang , Zhiqi Huang , Xiaolin Luo , Xinbo He , Yuhong Fang

In this paper, we test the cosmic distance duality (CDD) relation using the luminosity distances from joint light-curve analysis (JLA) type Ia supernovae (SNe Ia) sample and angular diameter distance sample from galaxy clusters. The…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-02 J. Hu , F. Y. Wang

The typical spectra of gamma-ray bursts (GRBs) are discussed in the context of the compactness problem for GRB sources and how it is resolved in the popular fireball model. In particular, observational (model-independent) constraints on the…

Astrophysics · Physics 2009-11-11 V. V. Sokolov , G. S. Bisnovatyi-Kogan , V. G. Kurt , Yu. N. Gnedin , Yu. V. Baryshev

The redshift-distance modulus relation, the Hubble Diagram, derived from Cosmological General Relativity has been extended to arbitrarily large redshifts. Numerical methods were employed and a density function was found that results in a…

General Physics · Physics 2008-10-03 John G. Hartnett

Gamma Ray Bursts (GRBs) are among the most powerful sources in the Universe: they emit up to 10^54 erg in the hard X-ray band in few tens of seconds. The cosmological origin of GRBs has been confirmed by several spectroscopic measurements…

Astrophysics · Physics 2011-07-19 G. Ghirlanda , G. Ghisellini , C. Firmani

It is usual, in gamma-ray burst (GRB) studies, to compare the average properties of bright and faint GRBs, with the assumption that brightness classes reflect distance classes. When brightness is intented to reflect the distance to the…

Astrophysics · Physics 2008-02-03 J-L. Atteia

The polarization of the cosmic microwave background (CMB) can be used to search for parity-violating processes like that predicted by a Chern-Simons coupling to a light pseudoscalar field. Such an interaction rotates $E$ modes into $B$…

In this work Gamma Ray Burst (GRB) data is used to place constraints on a putative coupling between dark energy and dark matter. Type Ia supernovae (SNe Ia) constraints from the Sloan Digital Sky Survey II (SDSS-II) first-year results, the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 T. Barreiro , O. Bertolami , P. Torres

Gamma-Ray Bursts (GRBs), observed at high-z, are probes of the evolution of the Universe and can be used as cosmological tools. Thus, we need correlations with small dispersion among key parameters. To reduce such a dispersion, we mitigate…

We use a new method of analysis to determine parameters of cosmological gamma-ray bursts (GRBs), assuming that their distribution follows the star-formation history of the universe. Spectral evolution is calculated from an external shock…

Astrophysics · Physics 2015-06-24 M. Boettcher , C. D. Dermer

Recent optical afterglow observations of gamma-ray bursts indicate a setting and distance scale that many relate to star-formation regions. In this paper, we use $<V/V_{max}>$ and a set of artificial trigger thresholds to probe several…

Astrophysics · Physics 2009-10-31 H. Che , Y. Yang , R. J. Nemiroff

The possibility to use $\gamma$--ray data from the Galactic Center (GC) to constrain the cosmological evolution of the Universe in a phase prior to primordial nucleosyntesis, namely around the time of cold dark matter (CDM) decoupling, is…

High Energy Physics - Phenomenology · Physics 2010-10-27 F. Donato , N. Fornengo , M. Schelke

In this note, we consider the observational constraints on some cosmological models by using the 307 Union type Ia supernovae (SNIa), the 32 calibrated Gamma-Ray Bursts (GRBs) at $z>1.4$, the updated shift parameter $R$ from WMAP 5-year…

Astrophysics · Physics 2009-03-23 Hao Wei

Gamma-ray bursts (GRBs) are challenging to identify due to their transient nature, complex temporal profiles, and limited observational datasets. We address this with a one-dimensional convolutional neural network integrated with an…

We collect and reanalyze about 200 GRB data of prompt-emission with known redshift observed until the end of 2009, and select 101 GRBs which were well observed to have good spectral parameters to determine the spectral peak energy ($E_p$),…

High Energy Astrophysical Phenomena · Physics 2015-06-03 Daisuke Yonetoku , Toshio Murakami , Ryo Tsutsui , Takashi Nakamura , Yoshiyuki Morihara , Keitaro Takahashi

Gamma-ray bursts (GRBs) are intense pulses of high-energy emission associated with massive stars' death or compact objects' coalescence. Their multi-wavelength observations help verify the reliability of the standard fireball model. We…

High Energy Astrophysical Phenomena · Physics 2024-11-19 M. G. Dainotti , S. Bhardwaj , E. Bissaldi , N. Fraija , S. Sourav , A. Galvan-Gamez
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