After years of focused research and more than 5 million hours of calculations on a supercomputer, the team created the world’s first high-resolution 3D radiative fluid dynamics for exotic supernovae. Provides information about this study Astrophysical Journal.

Ke-Jung Chen from the Academia Sinica Institute for Astronomy and Astrophysics (ASIAA) in Taiwan led an international team and used powerful supercomputers at Lawrence Berkeley National Laboratory and the National Astronomical Observatory of Japan to achieve this breakthrough. Supernova explosions are the most spectacular end for massive stars; Because they end their life cycle in a self-destructive way, they instantly release a brightness equivalent to billions of suns, illuminating the entire universe.

During this explosion, the heavy elements formed inside the star are thrown out, paving the way for the birth of new stars and planets and playing an important role in the origin of life. Supernovae are a subject of significant interest in modern astrophysics, covering many important astronomical and physical questions, both theoretical and observational, and are of significant research value.

Research over the past half century has provided a relatively complete understanding of supernovae. However, recent large-scale supernova observations reveal many unusual stellar explosions (exotic supernovae) that challenge and overturn previously established understandings of supernova physics.

The most surprising among exotic supernovae are glowing supernovae and constantly glowing supernovae. Supernovae are about 100 times brighter than normal supernovae, usually lasting only a few weeks to a few months.

In contrast, persistently bright supernovae can maintain their brightness for several years or even longer. Even more surprising, some exotic supernovae exhibit irregular and periodic fluctuations in brightness, similar to fountain explosions. These strange supernovae may hold the key to understanding the evolution of the largest stars in the universe.

The origin of these exotic supernovae is still not fully understood, but astronomers believe they may originate from unusually massive stars. As stars with a mass of 80-140 times the mass of the Sun approach the end of their lives, their cores undergo carbon synthesis reactions.

During this process, high-energy photons can create electron-positron pairs, causing vibrations in the nucleus and leading to many strong contractions. These contractions release large amounts of fusion energy and cause explosions that lead to massive explosions in stars. These explosions themselves may resemble ordinary supernovae. Additionally, when materials from different explosion periods collide, events similar to supernova stars can be created.

Currently, such massive stars are relatively rare in the universe, consistent with the scarcity of strange supernovae. Therefore, scientists suspect that stars with masses between 80 and 140 times the mass of the Sun are likely to be the precursors of strange supernovae. However, the unstable evolutionary structures of these stars make their simulations very difficult, and existing models are mostly limited to one-dimensional simulations.

However, previous one-dimensional models were found to have serious shortcomings. Supernova explosions cause significant turbulence, and turbulence plays a critical role in the explosion and brightness of supernovae. However, one-dimensional models cannot simulate turbulence from first principles. These difficulties have hindered a deep understanding of the physical mechanisms behind exotic supernovae in modern theoretical astrophysics.

This high-resolution simulation of supernova explosions presented enormous challenges. As the scale of simulations increased, it became increasingly difficult to maintain high resolution; this greatly increased the complexity and computational requirements and required the consideration of numerous physical processes.

Ke-Jung Chen emphasized that their team’s simulation code has advantages over other competing groups in Europe and America. Previous relevant simulations were mostly limited to one-dimensional and a few two-dimensional fluid models; whereas in exotic supernovae multidimensional effects and radiation play a crucial role in influencing light emission and overall explosion dynamics.

Hydrodynamic modeling of radiation takes into account the propagation of radiation and its interaction with matter. This complex process of radiative transfer makes calculations extremely difficult, with computational requirements and difficulties much higher than those of fluid simulations.

But thanks to the team’s extensive experience modeling supernova explosions and running large-scale simulations; They eventually succeeded in creating the world’s first three-dimensional radiation hydrodynamic simulation of exotic supernovae.

The research team’s findings show that the periodic explosion phenomenon in massive stars may have characteristics similar to many faint supernovae. When materials from different explosion periods collide, approximately 20-30% of the kinetic energy of the gas can be converted into radiation, explaining the supernova phenomenon.

Moreover, the radiative cooling effect causes the expelled gas to form a dense but irregular three-dimensional sheet structure, and this sheet layer becomes the main source of light emission in the supernova. The results of their modeling effectively explain the features of the observation of exotic supernovae mentioned above.

Thanks to advanced supercomputer simulations, this work takes an important step in elucidating the physics of exotic supernovae. As the next generation of supernova research projects begins, astronomers will discover more exotic supernovae, further shaping our understanding of the final stages and explosion mechanisms of ordinary massive stars.