Can someone please tell me the history of high-energy electron-positron collisions? In specific when was it discovered that such collisions can create hadrons? Any information would be useful. Thanks.
That does not answer your exact question - when was it discovered that you could make hadrons in electron-positron collisions - because, even before these colliders went online, physicists knew that you could produce pion pairs that way, and they were even able to estimate production cross sections. How they got there, I don't know, maybe it involved observing cosmic ray positrons somehow.
The hadron pair production e-+e+ → h-+h+ can be considered and calculated as a cross channel of the known elastic electron scattering off hadrons e-+h+ → e-+h+.
Thanks for your quick reply guys. A few more questions: In addition to creation via collisions are you aware of any other way that hadrons come about. For instance do charged proton-anti-proton pairs appear, theoretically, in electric fields via the Schwinger Effect?