The Carbon-Nitrogen-Oxygen Fusion Cycle



Simplified picture of the Carbon-Nitrogen-Oxygen fusion cycle
Click on image for full size (43K GIF)
When the temperature of the core of a star reaches about 16 million degrees Kelvin (that's REALLY hot!), Helium is made through another fusion cycle. This cycle is named the Carbon-Nitrogen-Oxygen (CNO) cycle. Here Carbon gets the cycle going, but it is not used up.

Watching the movie below may help you to understand this process.

Particle list for the movies (6K GIF)

Creating Carbon from Helium (744K MPEG)

Movie courtesy of University of Oregon

The Carbon-Nitrogen-Oxygen Fusion Cycle



Simplified picture of the Carbon-Nitrogen-Oxygen fusion cycle
Click on image for full size (43K GIF)
When the temperature of the core of a star reaches about 16 million degrees Kelvin (that's REALLY hot!), the production of Helium occurs through another fusion cycle. This cycle is named the Carbon-Nitrogen-Oxygen (CNO) cycle. Here Carbon gets the cycle going, but it is not used up.

Watching the movie below may help you to visualize this process.

Particle list for the movies (6K GIF)

Creating Carbon from Helium (744K MPEG)

Movie courtesy of University of Oregon

The Carbon-Nitrogen-Oxygen Fusion Cycle



Simplified picture of the Carbon-Nitrogen-Oxygen fusion cycle
Click on image for full size (43K GIF)
When the temperature of the core of a star reaches about 16 million degrees Kelvin the production of Helium occurs through another fusion cycle, called the Carbon-Nitrogen-Oxygen (CNO) cycle. Here Carbon acts as a catalyst, it participates in the reaction but it is not "burned".

The cycle involves a total of four protons that react one after the other with the heavy nucleus (Carbon first). After the first reaction Carbon is turned into Nitrogen, then Oxygen is produced that finally decays back into Carbon emitting an alpha particle (Helium nucleus). During the cycle two neutrinos, three photons and two antielectrons are also emitted. The antielectrons will annihilate with electrons producing two more photons.

Particle list for the movies (6K GIF)

Creating Carbon from Helium (744K MPEG)

Movie courtesy of University of Oregon


Last modified prior to September, 2000 by the Windows Team

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