GRB990123, a number of "firsts"
- brightest burst (top 0.3% in fluence)
- at z=1.6 intrinsically the most energetic burst
- first discovery of clear break in the optical afterglow
- first polarimetric observation in optical afterglow
- First radioflare (short lived radio emission)
- First prompt optical emission (ROTSE)
- X-ray afterglow too bright!
- First X-ray afterglow measured up to 60 keV
- First evidence of non-compliance with standard model
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