Abstract

High-precision measurements of electron-positron annihilation into final states of two, three, and four photons are presented. The data were obtained with the MAC detector at the PEP storage ring of the Stanford Linear Accelerator Center, at a center-of-mass energy of 29 GeV. The measured e+e−→γγ differential cross section is used to test the validity of quantum electrodynamics (QED) in this energy range; it agrees well with QED, and the limit on cutoff parameters for the electron propagator is Λ>66 GeV. The measurement of e+e−→γγγ is used to test the QED calculations of order α3 and to search for anomalies that would indicate the existence of new particles; the agreement with QED is excellent and no anomalies are found. Two events from the reaction e+e−→γγγγ are found, in agreement with the QED prediction.Received 23 June 1986DOI:https://doi.org/10.1103/PhysRevD.35.1©1987 American Physical Society

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.