Gamma Ray Bursts with BeppoSAX

Puzzling excess

X-ray emission

in the afterglow of

GRB990123

• Localizing GRBs: WFC-status report

• GRB990123, a number of "firsts"
  • prompt emission in gamma, X and optical range

  • extremely bright X-ray afterglow

  • peculiar optical afterglow

   

   

• First evidence of non-compliance with standard model