Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Measurements at CERN help to re-evaluate the element of life


Results from experiments at CERN and the Jyväskylä Accelerator Laboratory in Finland, reported in Nature today, cast new light on the primary reaction that creates carbon in stars. All the carbon in the Universe, including that needed for carbon-based life forms such as ourselves, has been made in the hearts of stars through what is known as the “triple alpha reaction”. The new findings modify the rate at which the reaction occurs and have broad implications for astrophysics, from the formation of the first stars to the creation of the heaviest elements in supernovae.

"The connection between the subatomic world and the cosmos is fascinating. The example of carbon is an old problem with contributions from many heroes in the field. It is a pleasure to be able to answer some of the questions they have left for us. It is the technological development in the intervening years, for example at ISOLDE, that has made this possible," says from Hans Fynbo of the University of Aarhus, lead author of the paper.

The big bang created mainly only hydrogen (mass 1) and helium (mass 4), because there are no long lived atomic nuclei with mass 5 and 8 to make the bridge to heavier elements such as carbon (mass 12). But in the hearts of stars the formation of carbon is possible through the triple-alpha reaction, where three helium nuclei (alpha particles) fuse to make to make a nucleus of carbon-12.

Rather than recreate the scorching conditions inside stars, the team from CERN and eight other European universities and institutes watched the reaction unfold in reverse, as nuclei of carbon-12 broke into three alpha particles. To do this, they created boron-12 and nitrogen-12, which are short-lived isotopes of the elements that flank carbon in the Periodic Table. The boron-12 was produced at CERN’s ISOLDE facility, while the nitrogen-12 was created at the IGISOL facility at the Jyväskylä Accelerator Laboratory at the University of Jyväskylä. These unstable nuclei soon transformed into carbon-12, through beta decay, in which a proton changes into a neutron or vice versa; the carbon-12 then broke into three alpha particles.

The ISOL method – isotope separation on line - originally pioneered and developed mainly at CERN played an important role in these experiments. “While ISOLDE at CERN could make the boron-12, IGISOL in Jyväskylä was needed to produce the nitrogen-12. This facility in Finland was specifically developed to complement ISOLDE’s performance through its ability to produce very short-lived radioisotopes of chemically reactive elements such as nitrogen," said Juha Äysto, head of the group responsible for the experiment at the University of Jyväskylä.

By measuring precisely the timing and energies of alpha particles shooting from the samples, the researchers were able to infer the energy states of the carbon nuclei just before decay. With this information in hand, they were able to determine the rate for the triple alpha process over a wide range of temperatures, from 0.01 – 10 billion K.

For the conditions in most stars, the researchers’ calculated rates for the triple alpha process agree with previous calculations. But their findings suggest the triple alpha rate at the relatively low temperatures of the Universe’s first stars (around 0.05 billion K), which began without carbon, was much faster. This in turn implies that the amount of carbon that could catalyze hydrogen burning in the first stars was produced twice as fast as previously thought.

At high temperatures, above 1 billion K, the new results indicate that the triple alpha process would work significantly slower than previous estimates, modifying the process of element production - nucleosynthesis – in supernovae. These explosions of old massive stars are a major source of the heaviest elements, those more massive than iron, through interactions in the surrounding shock wave. The new results suggest a reduction in the amount of nickel-56 produced with subsequent effects for heavier elements.

This work was carried by a team from CERN and eight other European universities and institutes.

James Gillies | alfa
Further information:

More articles from Physics and Astronomy:

nachricht Move over, lasers: Scientists can now create holograms from neutrons, too
21.10.2016 | National Institute of Standards and Technology (NIST)

nachricht Finding the lightest superdeformed triaxial atomic nucleus
20.10.2016 | The Henryk Niewodniczanski Institute of Nuclear Physics Polish Academy of Sciences

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

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

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Resolving the mystery of preeclampsia

21.10.2016 | Health and Medicine

Stanford researchers create new special-purpose computer that may someday save us billions

21.10.2016 | Information Technology

From ancient fossils to future cars

21.10.2016 | Materials Sciences

More VideoLinks >>>