|
Search over 100 encyclopedias and dictionaries: |
Research categories | Follow us on Twitter |
Research categories
View all topics in the newsView all reference sources at Encyclopedia.com |
|||
alpha particles
alpha particles (alpha rays) Stable, positively charged particle emitted spontaneously from the nuclei of certain radioactive isotopes undergoing alpha decay. They consist of two protons and two neutrons and are identical to the nuclei of helium atoms. Their penetrating power is low compared with that of beta particles (electrons) but they cause intense ionization along their track. This ionization is used to detect them. See also radioactivity; Rutherford
|
|
|
Cite this article
"alpha particles." World Encyclopedia. 2005. Encyclopedia.com. 1 Jun. 2012 <http://www.encyclopedia.com>. "alpha particles." World Encyclopedia. 2005. Encyclopedia.com. (June 1, 2012). http://www.encyclopedia.com/doc/1O142-alphaparticles.html "alpha particles." World Encyclopedia. 2005. Retrieved June 01, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O142-alphaparticles.html |
|
alpha particle
alpha particle one of the three types of radiation resulting from natural radioactivity . Alpha radiation (or alpha rays) was distinguished and named by E. R. Rutherford in 1909, who found by measuring the charge and mass of alpha particles that they are the nuclei of ordinary helium atoms. Alpha particles consist of two protons and two neutrons (see nucleus ). |
|
|
Cite this article
"alpha particle." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. 1 Jun. 2012 <http://www.encyclopedia.com>. "alpha particle." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. (June 1, 2012). http://www.encyclopedia.com/doc/1E1-alphapar.html "alpha particle." The Columbia Encyclopedia, 6th ed.. 2011. Retrieved June 01, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-alphapar.html |
|
alpha particle
alpha particle(α‐particle) The nucleus of a helium-4 atom. It consists of two protons and two neutrons and hence is positively charged. Alpha particles are emitted by the nuclei of atoms in a process of radioactive decay known as alpha decay.
|
|
|
Cite this article
"alpha particle." A Dictionary of Astronomy. 1997. Encyclopedia.com. 1 Jun. 2012 <http://www.encyclopedia.com>. "alpha particle." A Dictionary of Astronomy. 1997. Encyclopedia.com. (June 1, 2012). http://www.encyclopedia.com/doc/1O80-alphaparticle.html "alpha particle." A Dictionary of Astronomy. 1997. Retrieved June 01, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O80-alphaparticle.html |
|
Search over 100 encyclopedias and dictionaries:
HighBeam™ Research, Inc. © Copyright 2012. All rights reserved.
The Encyclopedia.com advertising network includes:
