The unexpected features of a kilonova, the colossal explosion triggered by colliding neutron stars, have been discovered.
A group of researchers while studying a long gamma – ray burst ( GRB ) have discovered the unexpected characteristics of a kilonova . This is the colossal explosion triggered by the collision of neutron stars. A discovery that challenges the theory that long GRBs are derived only from supernovae, end-of-life explosions of massive stars.
Gamma-ray bursts come in two types: long and short . The long ones last from a couple of seconds to a minute, the short ones less than two seconds. Longs are formed when a star with a mass 10 times that of the sun explodes. I brevi when two compact objects collide to form a kilonova. Observing the aftermath of a long GRB in 2021 they discovered the startling signs of a neutron star merger. Not therefore the expected signal of a supernova. In practice, it is the first time that a kilonova has been associated with a long GRB.
Most GRBs originate in the distant early universe. The farthest GRB ever recorded traveled nearly 13 billion years before being detected here on Earth. A distinguishing feature of the kilonova is its brightness at near-infrared wavelengths compared to the brightness in visible light. This difference in luminosity is due to the heavy elements expelled by the kilonova. They effectively block visible light while allowing longer wavelength infrared light to pass through unhindered.
Other teams have also independently studied this phenomenon arriving at the same conclusion. In addition to providing a better understanding of the nature of kilonovas and GRBs, this discovery allows for a new way to study gold formation . Experts can identify sites that create heavy elements by looking for the signature of a kilonova after a long-duration gamma-ray burst.
- Cosmic flash seen closest: kilonova discovery challenges our understanding of GRBs (meteoweb.eu)