GRB 200522A Kilonova = Geburt eines Magnetars? | - Der Treffpunkt für Astronomie

GRB 200522A Kilonova = Geburt eines Magnetars?


Am 26. Mai 2020 registrierte das Swift Observatorium den besonders intensiven Gamma Ray Burst GRB 200522A

Auf die Nachricht unterbrachen mehrere Observatorien ihr reguläres Beobachtungsprogramm, um an der berichteten Position nachzuschauen. Dazu gehörte auch das Hubble Space Telescope, welches ein starkes Signal im nahen Infrarot registrierte:

The Broad-band Counterpart of the Short GRB 200522A at z = 0.5536: A Luminous Kilonova ...

Die Interpretation läuft darauf hinaus, dass man die Verschmelzung (Merger) zweier Neutronensterne zu einem Magnetar beobachtet hat:

Birth of a magnetar from neutron star merger (Animation)

GRB 200522A.jpg

This image shows the glow from a kilonova caused by the merger of two neutron stars. The merger of the neutron stars is believed to have produced a magnetar, which has an extremely powerful magnetic field.
Credit: NASA, ESA, W. Fong (Northwestern University), and T. Laskar (University of Bath, UK)


This illustration shows the sequence for forming a magnetar-powered kilonova, whose peak brightness reaches up to 10,000 times that of a classical nova. 1) Two orbiting neutron stars spiral closer and closer together. 2) They collide and merge, triggering an explosion that unleashes more energy in a half-second than the Sun will produce over its entire 10-billion-year lifetime. 3) The merger forms an even more massive neutron star called a magnetar, which has an extraordinarily powerful magnetic field. 4) The magnetar deposits energy into the ejected material, causing it to glow unexpectedly bright at infrared wavelengths.
Credit: NASA, ESA, and D. Player (STScI)

Neutron star merger results in magnetar with brightest kilonova ever observed


Konnte man schon die Masse des Mergers bestimmen? Sollte dann doch schon recht nahe an der Grenze zu einem schwarzen Loch sein.


Schon spannend, diese kosmischen Ereignisse! Gravitationswellen hat man wohl nicht empfangen können?



Konnte man schon die Masse des Mergers bestimmen?
Gravitationswellen hat man wohl nicht empfangen können?
So weit ist man noch lange nicht. Es könnte auch einen Zusammenhang mit FRBs (Fast Radio Bursts) geben:


Astronomers have counted up to 118 FRBs so far (and there are hundreds more in the pipeline that still need to be verified), but until now none of them has been associated with a known source. The flashes are so brief - mere milliseconds long - that astronomers have struggled to localize them, relying mostly on the few that repeat. Whole new instruments have been constructed to find and pinpoint FRBs.

Now, in the November 4th Nature, international collaborations make it official: The radio-wave flash coming from the Milky Way magnetar was indeed an FRB, now designated FRB 200428. And it has seriously narrowed the playing field for explanations of these mysterious sources.

Wobei FRB200428 = SGR 1935+2154 eben jenes andere lokalisierte Ereignis war, welches einen Zusammenhang mit Magnetaren nahelegte: Magnetare - warum funktionieren die eigentlich?
Zuletzt bearbeitet: