Far out cosmology:another way carbon might have been made (Introduction)

by David Turell @, Friday, March 20, 2020, 21:10 (1707 days ago) @ David Turell

Fred Hoyle had a fusion in stars method of existing elements. This one uses neutron star collisions:

https://www.scientificamerican.com/article/carbon-conundrum-experiment-aims-to-re-creat...

"Our current understanding of the triple-alpha process largely came from astronomer Fred Hoyle, who famously predicted, in 1954, that a special excited state of carbon-12 must arise during synthesis. Later scientists observed this so-called Hoyle state and confirmed that the carbon then emitted gamma rays to de-excite down to its ground, or stable, state.

"Scientists have long suspected that other particles might play a role in that de-excitation, especially neutrons, which carry no electrical charge and can penetrate nuclei and take away extra energy. Measuring neutron energies has been difficult, however. A few years ago, physicist Lee Sobotka of Washington University in St. Louis decided the time was right to develop an experiment to test this idea.

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“'What we are doing here is to measure the cross section, or probability, of an inverse reaction of the original triple-alpha process,” Sobotka says. Because the Hoyle state can exist for only a blink of an eye, it is almost impossible to directly measure it. In the reverse reaction, neutrons will hit carbon nuclei, excite them to the Hoyle state, produce alpha particles and then leave the scene with a lower energy. “It’s a clever approach to measuring the probability that the Hoyle state is de-excited in a collision with the neutron by performing the inverse measurement,” says Martin Freer of the University of Birmingham in England, who is not involved in the experiment.

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"Once the data are available, the next step will be to invite astrophysicists to join the conversation and interpret the cosmic environment needed for such neutron-induced carbon formation, Sobokta says. The scenario could be quite different from the quiet burning processes in a star. It may be “a supernova or a neutron-star merger,” in which not only the density of particles is higher but more neutrons can be present, Freer says. Yet carbon created in such cataclysmic processes may not necessarily increase the total amount of carbon in the universe significantly because they act “as seeds for the synthesis of heavier elements produced in these explosions,” he notes. In other words, these carbon atoms may get absorbed in creating other members of the periodic table."

Comment: The research goes on and the idea is still based on Hoyle's concept. Carbon is the basis of the biochemistry of life and there is lots of it as part of the fine tuning of the universe for life.


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