An Energetic Blast Wave from the December 27 Giant Flare of the Soft Γ-ray Repeater 1806-20

/ 05 02 08 5 v 1 4 F eb 2 00 5 An energetic blast wave from the December 27 giant flare of the soft γ - ray repeater 1806 - 20

An Energetic Blast Wave from the 2004 December 27 Giant Flare of the Soft Gamma-ray Repeater Sgr

Recent follow-up observations of the 2004 December 27 giant flare of SGR 1806 20 have detected a multiplefrequency radio afterglow from 240 MHz to 8.46 GHz, extending in time from a week to about a month after the flare. The angular size of the source has also been measured for the first time. Here we show that this radio afterglow provides the first clear evidence of an energetic blast wave sw...

A Two-component Explosion Model for the Giant Flare and Radio Afterglow from Sgr1806-20

The brightest giant flare from the soft γ-ray repeater (SGR) 1806-20 was detected on 2004 December 27. The isotropic-equivalent energy release of this burst is at least one order of magnitude more energetic than those of the two other SGR giant flares. Starting from about one week after the burst, a very bright (∼ 80 mJy), fading radio afterglow was detected. Follow-up observations revealed the...

A Re-brightening of the Radio Nebula Associated with the 2004 December 27 Giant Flare from Sgr 1806–20

On 2004 Dec. 27, a giant γ-ray flare was detected from the magnetar SGR 1806–20. A radio observation seven days later revealed an expanding radio nebula at this position. Here we present results from an on-going monitoring campaign of this source with the Australia Telescope Compact Array and Very Large Array. These data indicate that there was an increase in the observed flux ∼25 days after th...

Pure and Loaded Fireballs in Soft Gamma-ray Repeater Giant Flares

On December 27, 2004, a giant flare from SGR 1806−20 was detected on earth. Its thermal spectrum and temperature suggest that the flare resulted from an energy release of about 1047 erg/sec close to the surface of a neutron star in the form of radiation and/or pairs. This plasma expanded under its own pressure producing a fireball and the observed gamma-rays escaped once the fireball became opt...