2021-07-08

Research: The star SMSS J200322.54-114203.3 may be formed in a “super supernova”

By yqqlm yqqlm

Research: The star SMSS J200322.54-114203.3 may be formed in a “super supernova”

It is reported that this star is located in the halo, approximately 7500 light years. It seems very old-it is a member of the second generation of stars born in the universe, dating back to 13 billion years ago.

In the sky observation, its metal content is very low compared to the same type of celestial body at the time (although in the astronomical sense, “metal” essentially refers to “anything heavier than helium”) . This is unusual in itself, but what is even more strange is that this star contains very high levels of heavy elements such as zinc, uranium, europium, and possibly even gold.

The corresponding author of this research paper, Dr. David Yong, said: “The star we are observing has about 3000 times lower iron and hydrogen than the sun, which means it is a very rare star: we Call it a star with extremely low metal content. However, the fact that it contains more heavy elements than expected means that it is rarer–it’s like looking for a needle in a haystack.”

Research: The star SMSS J200322.54-114203.3 may be formed in a “super supernova”(1)

The first-generation stars are mainly composed of hydrogen and helium. The heavier elements are only produced after they experience life, become supernovae, and collapse into neutron stars or black holes. When these neutron stars collide and merge, they produce more and heavier elements and release them into the universe.

The second-generation stars-some of which still exist today, such as J200322.54-were born in an environment that now has heavier elements, so trace elements are included. But in this case, the neutron star merger will not produce enough of these elements to explain the composition of the star.

So in this new study, astronomers investigated another possibility: a hypothetical star explosion that is far more powerful than an ordinary supernova explosion. The research team found that the abundance of these elements is consistent with the material ejected from a supernova with a mass of 25 suns. According to their calculations, the original star must spin very fast and possess a super strong magnetic field. After that, J200322.54 will be formed.

Chiaki Kobayashi, the co-author of this research paper, said: “The observational evidence we have now found directly indicates for the first time that there is a different type of supernova that produces all the stable elements in the periodic table at the same time- -The core of a rapidly rotating, strongly magnetized, massive star collapsed and exploded. This is the only thing that can explain the results.”

This study shows that the newly described mechanism may be the result of heavy elements in the early universe. Important sources, and studying other stars with strange compositions will help unlock more information.