Talk:CNO cycle

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"The CNO cycle may also be the dominant source of nitrogen and oxygen production"

Er, how? It doesn't create a net increase in the number of N or O nuclei. -- Bth

Maybe what is meant is that once there is carbon in the star, there will also be nitrogene and oxgene in a comparable amount. If there is no other direct synthesis for oxygene and nitrogene, then most of these two elements can come from aborted CNO cyles. andy 22:32, 29 Feb 2004 (UTC)

There is an equilibrium concentration N and O available in stars. When stars cool down, this can form N2 and O2. In heavier stars, when hydrogen/helium is depleted CNO starts reacting with other CNO molecules to form silicium (and slightly heavier components).

If the protons run out, you've still got a lot of CNO...Sikkema 14:23, 2 October 2007 (UTC)

Contents

[edit] energy notation

Is it a convention to write anenergy yield, so the liberation of energy, in the positive form ? This is contrary to chemical convention. Sikkema 14:23, 2 October 2007 (UTC)


[edit] HELP!!! :S

Hi i have a little question that you may just be able to help me with well here it goes... What type of radioactive particle was emitted by 13/7N and 15/7N? your help is much appriciated thank you

- 13N-> beta+ + 13C (no gamma) 15N stable, abundance 0.366%

[edit] Reference to the Bethe paper

The link below point to the paper of Hans Bethe in which he introduces the CNO cycle.

http://prola.aps.org/abstract/PR/v55/i5/p434_1

[edit] Bethe-Weizsäcker process

The german wiki calls it Bethe-Weizsäcker process is this also a name for it?--Stone 11:27, 30 June 2006 (UTC)

[edit] Initial synthesis of C, N & O

Out of interest, can anyone provide more information on where the elements in the CNO cycle come from? There doesn't appear to be any mechanism given in this article on how they're initially generated, and they aren't featured in the p-p chain. Do they then come from the triple alpha process? Thanks in advance --Xanthine 21:35, 29 July 2007 (UTC)