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carbon-nitrogen cycle[¦kär·bən ¦nī·trə·jən ‚sī·kəl]
A series of thermonuclear reactions, with release of energy, which presumably occurs in stars that are more massive than the sun; the net accomplishment is the synthesis of four hydrogen atoms into a helium atom, the emission of two positrons and much energy, and restoration of a carbon-12 atom with which the cycle began. Also known as carbon cycle; nitrogen cycle.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.