Superkilonova

News- Astronomers reported a possible first observation of a superkilonova in a study based on telescope and gravitational-wave data.

About superkilonova

• A superkilonova is a proposed cosmic explosion that combines the characteristics of a supernova and a kilonova in a single event.
• A kilonova occurs when two neutron stars collide, ejecting heavy radioactive elements such as gold, platinum, and neodymium.
• As these elements decay, they emit light mainly in the optical and infrared parts of the spectrum.
• A superkilonova differs because it has an additional energy source that makes the explosion brighter, bluer, and possibly longer lasting than a normal kilonova.

Formation Process

• A massive, rapidly rotating star runs out of nuclear fuel and undergoes a core-collapse supernova.
• Instead of forming one remnant, the collapsing core produces two neutron stars due to rapid rotation.
• This may occur through fission of the spinning core or through fragmentation, where a disk forms a second neutron star.
• The two newborn neutron stars form a tight binary system and spiral inward due to gravitational-wave emission.
• When the neutron stars merge, they trigger a kilonova explosion.
• The closely linked supernova and kilonova together appear as a combined event called a superkilonova.

Significance

• Element Factory: Like kilonovae, superkilonovae are key sites for creating heavy elements (gold, platinum, uranium).
• Black Hole Birth: They could explain how very massive black holes form.