Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Carbon, Carbon, Everywhere; But Not from the Big Bang

13.05.2011
As Star Trek is so fond of reminding us, we’re carbon-based life forms. But the event that jump-started the universe, the Big Bang, didn’t actually produce any carbon, so where the heck did it – and we – come from? An NC State researcher has helped create supercomputer simulations that demonstrate how carbon is produced in stars, proving an old theory correct.

More than 50 years ago, an astronomer named Fred Hoyle deduced that when three helium nuclei – or alpha particles – come together inside the core of a star, they have difficulty combining to form carbon-12, the stuff we’re made of.

So he predicted a new state of carbon-12, one with an energy tuned just right to make the formation of carbon possible in stars. This new state is now known as the Hoyle state. Later experimentation demonstrated that the theory was correct, but no one had ever been able to reproduce the Hoyle state from scratch, starting from the known interactions of protons and neutrons. If the Hoyle state didn’t show up in those calculations, then the calculations must be incorrect or incomplete.

NC State physicist Dean Lee, along with German colleagues Evgeny Epelbaum, Hermann Krebs, and Ulf-G. Meissner, had previously developed a new method for describing all the possible ways that protons and neutrons can bind with one another inside nuclei. This “effective field theory” is formulated on a complex numerical lattice that allows the researchers to run simulations that show how particles interact. When the researchers put six protons and six neutrons on the lattice, the Hoyle state appeared together with other observed states of carbon-12, proving the theory correct from first principles.

... more about:
»Big Bang »Carbon »Physic »Physical »alpha particles

“We’ve had simple models of the Hoyle state using three alpha particles for a long time, but the first principles calculations weren’t giving anything close,” Lee says. “Our method places the particles into a simulation with certain space and time parameters, then allows them to do what they want to do. Within those simulations, the Hoyle state shows up.”

Their research appears in the May 13 issue of Physical Review Letters.

Lee adds, “This work is valuable because it gives us a much better idea of the kind of ‘fine-tuning’ nature has to do in order to produce carbon in stars.”

The Department of Physics is part of NC State’s College of Physical and Mathematical Sciences.

-peake-

Note to editors: An abstract of the paper follows.
“Ab initio calculation of the Hoyle state”
Authors: Dean Lee, North Carolina State University; Evgeny Epelbaum and Hermann Krebs, Institut fur Theoretische Physik II, Ruhr-Universitat Bochum, Germany; Ulf-G. Meissner, Helmholtz-Institut fur Strahlen-und Kernphysik and Bethe Center for Theoretical Physics, Universitat Bonn, Germany
Published: in Physical Review Letters
Abstract:
The Hoyle state plays a crucial role in the helium burning of stars heavier than our sun and in

the production of carbon and other elements necessary for life. This excited state of the carbon-12 nucleus was postulated by Hoyle as a necessary ingredient for the fusion of three alpha particles to produce carbon at stellar temperatures. Although the Hoyle state was seen experimentally more than a half century ago nuclear theorists have not yet uncovered the nature of this state from first principles. In this letter we report the first ab initio calculation of the low-lying states of carbon-12 using supercomputer lattice simulations and a theoretical framework known as effective field theory. In addition to the ground state and excited spin-2 state, we find a resonance at −85(3) MeV with all of the properties of the Hoyle state and in agreement with the experimentally observed energy.

Tracey Peake | Newswise Science News
Further information:
http://www.ncsu.edu

Further reports about: Big Bang Carbon Physic Physical alpha particles

More articles from Earth Sciences:

nachricht NASA finds newly formed tropical storm lan over open waters
17.10.2017 | NASA/Goddard Space Flight Center

nachricht The melting ice makes the sea around Greenland less saline
16.10.2017 | Aarhus University

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Osaka university researchers make the slipperiest surfaces adhesive

18.10.2017 | Materials Sciences

Space radiation won't stop NASA's human exploration

18.10.2017 | Physics and Astronomy

Los Alamos researchers and supercomputers help interpret the latest LIGO findings

18.10.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>