space Paradigm Challenge

We used to think long cosmic explosions only came from dying stars, but some are actually from black holes smashing together.

arXiv · March 17, 2026 · 2603.15531

R. Maccary, C. Guidorzi, L. Amati, M. Bulla, S. Kobayashi, M. Maistrello, A. Rossi, G. Stratta, A.Tsvetkova

The Takeaway

Gamma-ray bursts are historically split into two strict camps: short ones from collisions and long ones from star deaths. This study identifies a hidden population of long-duration bursts that break this rule, proving that black hole and neutron star mergers can 'scream' much longer than we previously thought possible.

From the abstract

Context. The prompt-emission time profiles of GRB 230307A and other long-duration compact object merger (COM) candidates exhibit a unique set of temporal properties, characterised by a deterministic evolution of waiting times and pulse widths.Aims. We searched the Fermi/GBM catalogue for other unidentified long COM candidates exhibiting temporal properties similar to those observed in GRB 230307A.Methods. We examined the temporal and spectral prompt-emission properties of GRBs featuring at least