Post AxUM97yweosbeZM2DI by AlanSill@mast.hpc.social
 (DIR) More posts by AlanSill@mast.hpc.social
 (DIR) Post #AxUM96yuNTFwYAKUW8 by kwf@social.afront.org
       2025-08-24T05:07:42Z
       
       0 likes, 0 repeats
       
       Some times when reading vintage American textbooks, I start to wonder if they're just fucking with me on the units.
       
 (DIR) Post #AxUM97yweosbeZM2DI by AlanSill@mast.hpc.social
       2025-08-24T05:17:16Z
       
       0 likes, 1 repeats
       
       @kwf  Although the term did originate in the US, itʻs widely used throughout nuclear and particle physics internationally as a unit of cross section, conceptuallly the likelihood that particles will interact when crossing each other. It can be viewed as the effective size of the interaction window and so has units of area, as you probably know. Most interaction cross sections are small in these units and so a barn is pretty big. More on the history at: https://www.symmetrymagazine.org/article/february-2006/hitting-the-broad-side-of-a-classified-barn?language_content_entity=und