Gold is one of the most desirable metals in the world, but its formation from heavy metals such as gold, thorium, and uranium requires energetic conditions such as stellar explosions or collisions between neutron stars. This means that all heavy elements on Earth formed under extreme conditions in astrophysical environments.
Today, astrophysicists have an incomplete understanding of how elements heavier than iron are formed. Researchers are intrigued by the question of which of these astrophysical events create the right conditions for the formation of heavy elements. surprises, New study It shows that these elements can form in the accretion disks of black holes.
An accretion disk is called the circular chaos that surrounds a newborn active black hole as it swallows up dust and gas from the space around it. In these extreme environments, the high rate of neutrino emission should facilitate the conversion of protons into neutrons, which could lead to an increase in the latter, which is just what is needed for the process that produces the heavy elements.
“In our study, we systematically investigated for the first time the conversion rates of neutrons and protons for a large number of disk configurations using elaborate computer simulations, and found that disks are very rich in neutrons as long as certain conditions are met.” Explain Dr Oliver Just, from the Relativistic Astrophysics group in the Department of Theoretical Research at GSI.
just say AN: The decisive factor is the total mass of the disc. “The larger the disk, the more neutrons are formed from protons by electron capture under neutrino emission, and are available for the synthesis of heavy elements via the r process.”
On the contrary, if the mass of the disk is very high, the reverse reaction plays a more important role, so that the neutrinos are recovered to a greater extent by the neutrinos before leaving the disk. These neutrinos are converted back into protons, making the fast neutrino capture, or r process, difficult.
The study indicates that the optimum mass for the disk to become a factory for gold and other heavy materials ranges between 0.01 and 0.1 solar masses. Since it is currently unclear whether and how often these accretion discs occur in implosion systems, the research remains inconclusive.
“This data is currently insufficient. But with the next generation of accelerators, such as the Facility for Proton and Ion Research (FAIR), it will be possible to measure them with unprecedented precision in the future.” He said Astrophysicist Andreas Bauswin of the GSI Helmholtz Center for Heavy Ion Research.
It is known that a large number of elements are produced inside stars, but when we turn to elements heavier than iron, cataclysmic events are used literally. The most dangerous events occur during the birth of black holes. However, astrophysicists aren’t sure that conditions really exist, aside from the relative contributions of these factors to the overall abundance of heavy elements in the universe.
The team has been hard at work, using simulations to determine if this is indeed the case. We could rhetorically call it the magical moment when astrophysics and computing come together to retrace the history of the things we have in common today, but as we’ve seen, it has its origins in cosmic events that also include exotic black holes.
Research published in Monthly Notices of the Royal Astronomical Society.
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