402 citations · 1.7k across the 54 of their papers we have counts for
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The ultra-fast afterglow of GRB 260226A
Biswajit Banerjee, Alessio Mei, Annarita Ierardi +13
Long-duration gamma-ray bursts are typically powered by relativistic jets launched after the core collapse of some rapidly rotating massive stars. Internal dissipation releases par…
Colour evolution in the radio afterglow of GRB 241025A
S. Giarratana, O. S. Salafia, L. Nava +10
We present the observing campaign of the afterglow of GRB241025A, a gamma-ray burst (GRB) whose prompt emission has been simultaneously detected by Swift, Einstein Probe, Fermi/GBM…
Early Optical Follow-up of Gamma-Ray Bursts: The Critical Role of Robotic Telescopes
Rahul Gupta, Judith Racusin, Gor Oganesyan +26
Gamma-ray bursts (GRBs) are the most luminous electromagnetic explosions in the Universe, and offer unique laboratories for studying relativistic jets, compact-object formation, pa…
Thermal Electrons in an Ultra-Relativistic Shock Shape the Optical Afterglow of GRB 250702F
Martin Jelínek, Annarita Ierardi, Filip Novotný +8
Observing early optical emission from gamma-ray bursts (GRBs) contemporaneous with the MeV prompt emission phase remains rare, requiring rapid-response robotic facilities. The Ondř…
MeV absorption in gamma-ray bursts as a probe of their progenitor environments
Gor Oganesyan, Om Sharan Salafia, Emanuele Sobacchi +8
A small fraction of X-ray photons from -ray bursts (GRBs), after escaping the relativistic jet, are scattered by electrons in the circumburst medium. Subsequent photon-photon ab…
Early X-ray emission of short Gamma-Ray Bursts: insights into physics and multi-messenger prospects
Annarita Ierardi, Gor Oganesyan, Stefano Ascenzi +3
Early X-ray emission of Gamma-Ray Bursts (GRBs) traces the transition between the prompt emission and the afterglow radiation, and its rapid flux decline is often interpreted as th…
Broadband Modelling of GRB 230812B Afterglow: Implications for VHE -ray Detection with IACTs
Shraddha Mohnani, Biswajit Banerjee, Davide Miceli +13
A significant fraction of the energy from the -ray burst (GRB) jets, after powering the keV-MeV emission, forms an ultra-relativistic shock propagating into the circumburst medi…
Ultra-long MeV transient from a relativistic jet: a tidal disruption event candidate
Gor Oganesyan, Elias Kammoun, Annarita Ierardi +11
On July 2, 2025, the Gamma-ray Burst Monitor (GBM) onboard the Fermi Gamma-ray space telescope detected three short-duration MeV transients with overlapping sky locations. These ev…
Gamma-ray burst prompt emission spectra at high energies
Samanta Macera, Biswajit Banerjee, Alessio Mei +3
Despite more than fifty years of gamma-ray burst (GRB) observations, several questions regarding the origin of the prompt emission, particularly at high energies, remain unresolved…
Prospects for optical detections from binary neutron star mergers with the next-generation multi-messenger observatories
E. Loffredo, N. Hazra, U. Dupletsa +13
Next-generation gravitational wave (GW) observatories, such as the Einstein Telescope (ET) and Cosmic Explorer, will observe binary neutron star (BNS) mergers across cosmic history…
Gamma-ray burst spectral-luminosity correlations in the synchrotron scenario
Alessio Mei, Gor Oganesyan, Samanta Macera
For over two decades, gamma-ray burst (GRB) prompt emission spectra were modelled with smoothly-broken power laws (Band function), and a positive and tight correlation between the…
Camelidae on BOAT: observation of a second spectral component in GRB 221009A
Biswajit Banerjee, Samanta Macera, Alessio Ludovico De Santis +8
Observing and understanding the origin of the very-high-energy (VHE) spectral component in gamma-ray bursts (GRBs) has been challenging because of the lack of sensitivity in MeV-Ge…
A bright megaelectronvolt emission line in -ray burst GRB 221009A
Maria Edvige Ravasio, Om Sharan Salafia, Gor Oganesyan +13
The highly variable and energetic pulsed emission of a long gamma-ray burst (GRB) is thought to originate from local, rapid dissipation of kinetic or magnetic energy within an ultr…
Pre-merger alert to detect the very-high-energy prompt emission from binary neutron-star mergers: Einstein Telescope and Cherenkov Telescope Array synergy
Biswajit Banerjee, Gor Oganesyan, Marica Branchesi +8
The current generation of very-high-energy ray (VHE; E above 30 GeV) detectors (MAGIC and H.E.S.S.) have recently demonstrated the ability to detect the afterglow emission…
Combined X-ray and optical analysis to probe the origin of the plateau emission in -ray bursts afterglows
Samuele Ronchini, Giulia Stratta, Andrea Rossi +5
A large fraction of gamma-ray bursts (GRBs) shows a plateau phase during the X-ray afterglow emission, whose physical origin is still debated. In this work we define a sample of 30…
Neutrino search from γ-ray bursts during the prompt and X-ray afterglow phases using 10 years of IceCube public data
Francesco Lucarelli, Gor Oganesyan, Teresa Montaruli +5
Neutrino emission from gamma-ray bursts (GRBs) has been sought for a long time, and stringent limits on the most accredited GRB emission models have been obtained from IceCube. Mul…
GeV emission from a compact binary merger
Alessio Mei, Biswajit Banerjee, Gor Oganesyan +9
An energetic -ray burst (GRB), GRB 211211A, was observed on 2021 December 11 by the Neil Gehrels Swift Observatory. Despite its long duration, typically associated with burs…
Perspectives for multi-messenger astronomy with the next generation of gravitational-wave detectors and high-energy satellites
Samuele Ronchini, Marica Branchesi, Gor Oganesyan +6
The Einstein Telescope (ET) is going to bring a revolution for the future of multi-messenger astrophysics. In order to detect the counterparts of binary neutron star (BNS) mergers…
Constrains on the physics of the prompt emission from a distant and energetic gamma-ray burst GRB 220101A
Alessio Mei, Gor Oganesyan, Anastasia Tsvetkova +6
The emission region of -ray bursts (GRBs) is poorly constrained. The uncertainty on the size of the dissipation site spans over 4 orders of magnitude (…
Exceptionally bright optical emission from a rare and distant ray burst
Gor Oganesyan, Sergey Karpov, Martin Jelínek +19
Long -ray bursts (GRBs) are produced by the dissipation of ultra-relativistic jets launched by newly-born black holes after the collapse of massive stars. Right after the lu…
The slope of the low energy spectrum of Gamma-Ray Burst prompt emission
M. Toffano, G. Ghirlanda, L. Nava +3
Gamma-ray Bursts (GRBs) prompt emission spectra are often fitted with the empirical ''Band" function, namely two power laws smoothly connected. The typical slope of the low energy…
Electromagnetic Counterparts of Compact Binary Mergers
Stefano Ascenzi, Gor Oganesyan, Marica Branchesi +1
The first detection of a binary neutron star merger through gravitational waves and photons marked the dawn of multi-messenger astronomy with gravitational waves, and it greatly in…
Spectral index-flux relation for investigating the origins of steep decay in -ray bursts
Samuele Ronchini, Gor Oganesyan, Marica Branchesi +9
-ray bursts (GRBs) are short-lived transients releasing a large amount of energy ( erg) in the keV-MeV energy range. GRBs are thought to originate from interna…
X-ray plateaus in -ray bursts explained by structured jets
Gor Oganesyan
The follow-up of -ray bursts (GRBs) by the X-ray telescope (XRT, 0.3-10 keV) on board the Neil Gehrels Swift Observatory led to the discovery of a shallow decay phase (the so-ca…