The collision of neutron stars left a long trail: astronomers are surprised by X-rays

Neutron stars leave X-rays after merging

The scientists are surprised by the X-rays persisting that persist long after neutron stars collide. That stellar behavior, according to the astronomers, provides a complete new understanding of the process of neutron star merging. Three years have passed since the first that process, which the scientists called historical. Since then, an international team of scientists led by the University of Maryland has been observing the effects of neutron star mergers.

They are expressed in constant emission of radiation. They are trying to explain what is happening, because earlier models predicted that the X-rays would stop after the merger. By constantly monitoring the radiation associated with a single cosmic event of its kind, the astronomers are finding a new phase in understanding the interactions of neutron stars.

An astronomer Eleanor Troy notes that she and her colleagues were surprised to see the X-rays even 1000 days after the collision of neutron stars. Finding an answer to what is really happening can take years. The merger of neutron stars GW170817 was first identified by gravitational waves. They were recorded by the equipment installed in the observatory with a laser interferometer. The phenomenon took place in the constellation Virgo and was observed on August 17, 2017.

For several hours, the telescopes around the world have been recording powerful electromagnetic radiation emanating from the explosion provoked by the merger. A few seconds after the discovery of the phenomenon, the scientists recorded the first stream of gamma-ray burst energy, and then a slower one, in the form of a cloud of gas.

The light from the kilon jet was scattered for three weeks, and then completely extinguished. Nine days after detecting the first gravitational wave, the telescopes discovered something that shouldn't be the X-rays from the scene.

Models based on well-known astrophysics predicted that the initial jet of energy from the collision of neutron stars could travel through space, creating its own shock wave that forms the X-rays, a beam of radio waves and a glow. But nothing like that had ever been observed before.

The postglow reached its maximum after 160 days and then disappeared, but the X-rays remained. The astronomers believe these rays represent a completely new feature of the collision afterglow, and the dynamics of the gamma-ray burst is significantly different from what is expected.