Physics

The Columbia Encyclopedia, 6th ed. A Dictionary of Architecture and Landscape Architecture Further reading

barn

The Columbia Encyclopedia, 6th ed. | 2011 | Copyright

barn abbr. b, in physics, unit of nuclear cross section, i.e., the effective target presented by a nucleus for collisions leading to nuclear reactions; it is equal to 10 ^-24 square centimeters. The barn is approximately the size of the geometric cross section of an atomic nucleus; the term was coined because an effective cross section that large would present a target "as big as a barn," i.e., an easy target for nuclear bombardment. In practice, effective cross sections of nuclei for many reactions are measured in millibarns (10 ^-3 barn) because, for most interactions, only a small fraction of collisions cause reactions.

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barn

A Dictionary of Architecture and Landscape Architecture | 2000 | | Copyright

barn. Building to store agricultural produce, especially grain, to protect it from the weather. Barns of the Middle Ages often had architectural pretensions. Examples include the C13 barn at Great Coxwell, Berks., and the (probably) C12 barley-barn at Cressing Temple, Essex, both with timber nave-and-aisle interiors.

Bibliography

Endersby et al . (1992);
Kirk (1994)

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JAMES STEVENS CURL. "barn." A Dictionary of Architecture and Landscape Architecture. 2000. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>.

JAMES STEVENS CURL. "barn." A Dictionary of Architecture and Landscape Architecture. 2000. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O1-barn.html

JAMES STEVENS CURL. "barn." A Dictionary of Architecture and Landscape Architecture. 2000. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O1-barn.html

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Free newspaper and magazine articles

	Barns reveal character of their owners Weathered wood, maint mute testament... Newspaper article from: Daily Herald (Arlington Heights, IL); 11/28/1997
	Barns: 'The Loss of an Era' Local farmland, historic barns disappear only to... Newspaper article from: Daily Herald (Arlington Heights, IL); 1/19/2004
	Barn tour to highlight vanishing American icons.(Neighbor) Newspaper article from: Daily Herald (Arlington Heights, IL); 10/7/2004