An upper limit to the energy of gamma-ray bursts indicates that GRB/SNe are powered by magnetars

TL;DR

The paper suggests that the maximum energy observed in gamma-ray burst-associated supernovae aligns with the rotational energy of magnetars, proposing magnetars as the central engine for these luminous events.

Contribution

It introduces the idea that magnetars are the power source for GRB/SNe based on energy limits, contrasting with black hole models and explaining XRFs.

Findings

Supernova kinetic energy clusters near 2×10^52 erg.

This energy matches the maximum rotational energy of a 1 ms neutron star.

XRFs are linked to weaker magnetic fields or slower spins.

Abstract

The kinetic energy of supernovae (SNe) accompanied by gamma-ray bursts (GRBs) tends to cluster near E52 erg, with 2.E52 erg an upper limit to which no compelling exceptions are found (assuming a certain degree of asphericity), and it is always significantly larger than the intrinsic energy of the GRB themselves (corrected for jet collimation). This energy is strikingly similar to the maximum rotational energy of a neutron star rotating with period 1 ms. It is therefore proposed that all GRBs associated with luminous SNe are produced by magnetars. GRBs that result from black hole formation (collapsars) may not produce luminous SNe. X-ray Flashes (XRFs), which are associated with less energetic SNe, are produced by neutron stars with weaker magnetic field or lower spin.