2005/03/02 by D. M. Palmer, S. D. Barthelmy, S. Barthelmy +34 · 15 citations
Physics and Astronomy · #Astronomy #Astrophysical Phenomena and Observations #Astrophysics #Flare #Gamma-ray bursts and supernovae #Glitch #Magnetar #Neutron star #Physics #Pulsar #Pulsars and Gravitational Waves Research #Solar flare #Stars #astro-ph
paper · pdf · doi:10.1038/nature03525
published as Nature 434 (2005) 1107-1109 · Submitted to Nature 2005-02-02, revised 2005-03-01. 21 pp, incl. 6 figures
arxiv created 2005/03/02 · openalex publication_date 2005/04/01 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Magnetars comprise two classes of rotating neutron stars (Soft Gamma Repeaters (SGRs) and Anomalous X-ray Pulsars), whose X-ray emission is powered by an ultrastrong magnetic field, B ~ 1015 G. Occasionally SGRs enter into active episodes producing many short X-ray bursts; extremely rarely (about once per 50 years per source), SGRs emit a giant flare, an event with total energy at least 1000 times higher than their typical bursts. Here we report that, on 2004 December 27, SGR 1806-20 emitted the brightest extra-solar transient event ever recorded, even surpassing the full moon brightness for 0.2 seconds. The total (isotropic) flare energy is 2x1046 erg, 100 times higher than the only two previous events, making this flare a once in a century event. This colossal energy release likely occurred during a catastrophic reconfiguration of the magnetar's magnetic field. Such an event would have resembled a short, hard Gamma Ray Burst (GRB) if it had occurred within 40 Mpc, suggesting that extragalactic SGR flares may indeed form a subclass of GRBs.