The following sections of this BookRags Literature Study Guide is offprint from Gale's For Students Series: Presenting Analysis, Context, and Criticism on Commonly Studied Works: Introduction, Author Biography, Plot Summary, Characters, Themes, Style, Historical Context, Critical Overview, Criticism and Critical Essays, Media Adaptations, Topics for Further Study, Compare & Contrast, What Do I Read Next?, For Further Study, and Sources.
(c)1998-2002; (c)2002 by Gale. Gale is an imprint of The Gale Group, Inc., a division of Thomson Learning, Inc. Gale and Design and Thomson Learning are trademarks used herein under license.
The following sections, if they exist, are offprint from Beacham's Encyclopedia of Popular Fiction: "Social Concerns", "Thematic Overview", "Techniques", "Literary Precedents", "Key Questions", "Related Titles", "Adaptations", "Related Web Sites". (c)1994-2005, by Walton Beacham.
The following sections, if they exist, are offprint from Beacham's Guide to Literature for Young Adults: "About the Author", "Overview", "Setting", "Literary Qualities", "Social Sensitivity", "Topics for Discussion", "Ideas for Reports and Papers". (c)1994-2005, by Walton Beacham.
All other sections in this Literature Study Guide are owned and copyrighted by BookRags, Inc.
Hadrons are subatomic particles that are affected by the strong force, the force that binds the nucleus together. Two hadrons--the proton and the neutron--are found in the atomic nucleus. All others are created by high-energy collisions, from cosmic rays and particle accelerators. Hadrons are combinations of basic particles, quarks and gluons, held together by the strong force. Quarks contribute mass and determine the hadrons properties, including electronic charge and spin. Gluons carry the strong force and hold the quarks together. All known subatomic particles except bosons (such as photons) and leptons (such as electrons and neutrinos) are hadrons. They are divided into two categories: baryons, made of three quarks, and mesons, made of a quark and an anti-quark.
All mesons and all the baryons, except the proton, are unstable and decay into other particles. Most of them exist for less than a millionth of a second, and some can survive only for the amount of time that it takes for a light wave to pass from one side to the other. Their existence is known by observation of the products and process of particle decay. Although a free neutron will decay in an average of about 15 minutes, neutrons bound within an atomic nucleus are stable. Some theories indicate that the proton may have some instability, but its half-life is very much longer than the age of the universe.
Particle physicists have discovered a large number of hadrons. The Review of Particle Physics, published every other year, contains more than 300 pages, listing particle types and their observed decay processes.