Gamma-ray burst
GRB 031203
GRB011211
GRB090423
GRB090423
GRB130925A
GW170817
Gamma-ray BurstsThe XMM-Newton team is making a big effort to observing Gamma Ray Bursts (GRB) in response to alerts provided by other higher-energy observatories. The absolute minimum reaction time reached is 6-8 hours after the alert. In all observations (conducted as Target Of Opportunity observations) the GRB afterglow has been detected and much has been learned of this phenomenon from the X-ray data.Perhaps the most interesting (first) case is that of GRB011211: [Ref 9] during the early 10 ks of that observation, the EPIC X-ray spectrum showed emission lines which were identified as Mg XI, Si XIV, SXVI, Ar XVIII and Ca XX but at a significantly blueshifted velocity ~0.1 c. If this interpretation is correct, then this would provide direct evidence for outflowing material. [Ref 4] Strong, delayed X-ray line emission was also detected with XMM-Newton in the afterglow of GRB 030227 near the end of the observations, about twenty hours after the burst: the observed flux in the X-ray lines sharply increased from an undetectable level (<1.7 10-14 erg/cm2/s, 3 sigma) to 4.1 10-14 erg/cm2/s in the final 9.7 ks. [Ref 21] These results seem to support the hypothesis that afterglows of long-duration GRBs have massive star progenitors with a catastrophic endpoint that seems to produce both a GRB and a supernova. |
| Gamma-ray burst | GRB 031203 | GRB011211 | GRB090423 | GRB090423 |
| GRB130925A | GW170817 |