When the largest stars in the universe run out of fuel, they explode as supernovas, collapsing inward and leaving behind a neutron star or black hole, or evaporate altogether.
Understanding what’s happening inside the unfolding explosion is difficult, especially for so-called exotic supernovae, the rarest and brightest types of stellar explosions.
To better understand the dynamics of these rare supernovae, astronomers use powerful supercomputers to simulate the process. After years of real-world research and millions of hours of supercomputing time, researchers have completed the first high-resolution 3D hydrodynamic simulations of exotic supernovae.
Ki-Jong Chen of the Academia Sinica Institute for Astronomy and Astrophysics (ASIAA) in Taiwan led an international team and used supercomputers at Lawrence Berkeley National Laboratory and the National Astronomical Observatory in Japan. They published their findings in Astrophysical Journal.
Supernovas are magnificent, powerful explosions that mark the end of the lives of massive stars, and astronomers have a relatively comprehensive understanding of these explosions.
For example, for the majority of supernovae, their intrinsic brightness is always known, and scientists have been able to create computer models of what happens during a supernova explosion.
But in recent years, large-scale supernova observations have revealed rare types of cosmic explosions, one tens to hundreds of times brighter than normal supernovas, and others lasting for extremely long periods of time. These rare events, called exotic supernovae, challenge and overturn previously established understanding of supernova physics.
Superluminous supernovae are about 100 times brighter than ordinary supernovae, which typically maintain their brightness for only a few weeks to a few months.
Eternally luminous supernovae can maintain their brightness for several years or even longer. Other exotic supernovae show irregular and intermittent variations in brightness.
Suspects for the strange supernova are stars with masses ranging from 80 to 140 times the mass of the Sun. Scientists say that learning more about these unusual supernovae may hold the key to understanding the evolution of the most massive stars in the universe.
However, modeling what happens during these massive explosions is extremely difficult, and in this new paper, Ke-Jung Chen and his team say current models have been mainly limited to one-dimensional simulations.
Using state-of-the-art supercomputer simulations and millions of hours of computing time, researchers were able to model how turbulent structures in the interior of an exotic supernova explosion affect the brightness and explosion structure of the entire supernova.
“Turbulence plays a crucial role in the supernova explosion process, resulting from irregular fluid motion, leading to complex dynamics,” the team wrote.
“These turbulent structures mix and deform matter, affecting the release and transfer of energy, and thus affecting the brightness and appearance of the supernova.”
The team said more research is necessary to further understand strange supernovae, especially as next-generation supernova survey projects are likely to detect more such events.
The Vera Rubin Telescope in Chile is expected to detect three to four million supernovae during its decade-long survey over a wide range of distances. In addition, large-scale near-infrared missions, such as the Nancy Grace Roman Space Telescope and Euclid, will reveal more of these events.
Learning more about them through computer simulations and modeling will help increase our understanding of the death of very massive stars.
This article was originally published by Universe Today. Read the original article.
#model #strange #supernova #million #hours
