Archived posting to the Leica Users Group, 2003/09/02
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]On 9/2/03 eric@jphotog.com (Eric Welch) thoughtfully wrote: >Wow! in the midwest our barns were much bigger! :-) >I did a photo essay on barns once. Grin - yep by lots. The barn is used as a measure of things like the absorbtion cross-section of a nucleus - which is a measure of the probability of a nucleus interacting with, say a neutron of a particular energy. Typical values range from numbers less than one to values of around 3,000,000 barns (for Xenon 135 which is a major fission-product). The control rods in nuclear reactors have cross sections for neutron absorbtion in the range of 300-500 barns. Look at it this way: you don't have to invest in a lot of paint for one of these...but the lighting is a bit tricky too. AB - -- To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html