Symposium S9  3-4 July 2024

Gamma-ray bursts: a dynamic puzzle yet to be composed

Aims and scope

Half a century after the discovery of gamma-ray bursts (GRBs), a broad picture has emerged to explain the most powerful electromagnetic sources in the Universe. This picture includes two different progenitor channels (massive stars and binary compact object mergers), both leading to the formation of a central engine (an accretion-powered black hole or magnetar) capable of funneling baryon and magnetic energy into relativistic jets. Eventually, their energy is dissipated producing the prompt (gamma-ray) and afterglow (radio to TeV) emission.

Despite decades of observations, the last five years have seen new surprising discoveries, which have challenged key elements of this "standard model". The opening of the multi-messenger window, while directly tying short GRBs with binary mergers, has called for a substantially improved description of the jet dynamics and structure, also in light of the parent GRB population of orphan afterglows. Long-duration GRBs originated by binary mergers have blurred the historically established distinction between long and short GRBs, with implications for both populations, their tie to cosmic star formation and heavy element production. The discovery of very high energy (TeV) emission has reopened the question about dissipation and radiative processes during both the prompt and afterglow phases. In particular, exceptionally energetic events have pushed to their limits progenitor models and the properties of their environments. Such a fast evolving picture comes directly from the legacy of the Swift and Fermi spacecrafts, as well as the ground-based follow-up efforts.

In the next decade, the observational picture is going to be enriched and revolutionized by new GRB missions (like SVOM and Einstein Probe) and by the ongoing and forthcoming GW interferometers runs. So far, interpreting GRB features has proceeded along quite independent research pathways. It is time to critically review and discuss multi-wavelength and multi-messenger observations and their theoretical interpretation, in order to start redesigning the overall picture. The goal of this symposium is to establish a collaborative link among the many European researchers who have grown their expertise in the many branches of this field.


The proposed symposium aims at addressing the following topics, both from an observational and a theoretical perspective:

  • progenitors
  • central engines and jets
  • GRB emission from radio to TeV
  • GRBs as probes
  • GRBs as multi-messenger sources
  • the next decade of GRB science

Invited speakers

  • Bertrand Cordier (Université Paris-Saclay, FR)
  • Andrew Levan (Radboud University, NL)
  • Raffaella Margutti (University of California, Berkeley, USA)
  • Lara Nava (INAF - Osservatorio Astronomico di Brera, IT)
  • Om Sharan Salafia (INAF - Osservatorio Astronomico di Brera, IT)
  • Patricia Schady (University of Bath, UK)

Scientific organisers

  • Paolo D'Avanzo (co-chair; INAF-Osservatorio Astronomico di Brera, Italy)
  • Susanna Vergani (co-chair; GEPI, Observatoire de Paris, Université PSL, CNRS France)
  • Maria Grazia Bernardini (INAF-Osservatorio Astronomico di Brera, Italy)
  • Frédéric Daigne (Sorbonne Université, CNRS, Institut d'Astrophysique de Paris, France)
  • Phil Evans (University of Leicester, United Kingdom)
  • Giancarlo Ghirlanda (INAF-Osservatorio Astronomico di Brera, Italy)
  • Andreja Gomboc (University of Nova Gorica, Slovenia)
  • Daniele Bjørn Malesani (Cosmic Dawn Center, Niels Bohr Institute, University of Copenhagen, Denmark / Department of astrophysics, IMAPP, Radboud University, The Netherlands)
  • Kim Page (University of Leicester, United Kingdom)
  • Maria Petropoulou (National and Kapodistrian University of Athens / Institute of Accelerating Systems & Applications, Greece)
    • Contact

    • paolo.davanzo AT
    • susanna.vergani AT
    • Updated on Fri Feb 09 12:51:17 CET 2024