November 2, 2024

Probing Mysterious “Afterglow” X-Ray Remnants From Extreme Cosmic Bursts of Light

For each short gamma-ray burst, the outcomes recommended that the residue neutron star is a millisecond magnetar: a neutron star with an extraordinarily effective magnetic field.

Brief gamma-ray bursts are extremely intense bursts of high-energy light that last for a couple of seconds. If the remnant of a brief gamma-ray burst is a neutron star, it should have a similar energy outflow as a supernova residue.

In our study, we obtained the fundamental physics from previous brief gamma-ray burst models to anticipate the luminosity and period of the X-ray plateau. For each brief gamma-ray burst, the outcomes recommended that the remnant neutron star is a millisecond magnetar: a neutron star with an extraordinarily effective electromagnetic field. All known magnetars have an extremely slow rotation frequency; similarly, all observed neutron stars with millisecond spins have weak electromagnetic fields. This gap in observations isnt unexpected because the electromagnetic field of the star converts the rotational energy into electromagnetic energy. For a magnetar-strength field, this procedure happens on a scale from seconds to days– precisely the period of most X-ray plateaux.
This paper is the very first effort at estimating the source of X-ray afterglows using this sort of model. As the model grows and more information is collected, well have the ability to make stronger conclusions about the source of X-ray plateaux and, if were fortunate, discover what these mysterious remnants are.
Referral: “Inferring homes of neutron stars born simply put gamma-ray bursts with a plerion-like X-ray plateau” by L. C. Strang, A. Melatos, N. Sarin and P. D. Lasky, 4 August 2021, Monthly Notices of the Royal Astronomical Society.DOI: 10.1093/ mnras/stab2210.

Artists impression of a gamma-ray burst. Credit: Carl Knox, OzGrav-Swinburne
Brief gamma-ray bursts are extremely bright bursts of high-energy light that last for a number of seconds. In a number of these bursts, there is a mystical material left behind: an extended afterglow of radiation, including X-rays. Despite the efforts of numerous researchers over many years, we still dont know where this afterglow originates from.
In our current paper in the Monthly Notices of the Royal Astronomical Society, we examined a simple model that proposes a turning neutron star– an extremely dense collapsed core of a massive supergiant star– as the engine behind a type of prolonged X-ray afterglows, referred to as X-ray plateaux. Utilizing a sample of six short gamma-ray bursts with an X-ray plateau, we exercised the homes of the main neutron star and the mystical residue surrounding it.
The model we utilized was influenced by residues from young supernova. While remnants from brief gamma-ray bursts and supernovae have lots of distinctions, the energy driving from a turning neutron star has the exact same underlying physics. So, if the remnant of a short gamma-ray burst is a neutron star, it needs to have a comparable energy outflow as a supernova remnant.