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Title: Measuring W photon couplings in a 500 GeV e sup + e sup - collider

Technical Report ·
DOI:https://doi.org/10.2172/5179194· OSTI ID:5179194

The Standard Model gives definite predictions for the W-photon couplings. Measuring them would test an important ingredient of the model. In this work we study the capability of a 500 GeV e{sup +}e{sup {minus}} collider to measure these couplings. We study the most general C and P conserving WW{lambda} vertex. This vertex contains two free parameters, {kappa} and {lambda}. We look at three processes: e{sup +}e{sup {minus}} {yields} W{sup +}W{sup {minus}}, e{lambda} {yields} W{nu} and {lambda}{lambda} {yields} W{sup +}W{sup {minus}}. For each process we present analytical expressions of helicity amplitudes for arbitrary values of {kappa} and {lambda}. We consider three different sources for the initial photon(s). The first two are breamsstrahlung and beamstrahlung (photon radiation induced by the collective fields of the opposite bunch). Both occur naturally in the collider environment. The third is a photon beam generated by scattering low energy laser light off a high energy electron beam. We examine potential observables for each process, calculating their sensitivity to {kappa} and {lambda}, and estimating the accuracy with which they can be measured. Assuming Standard Model values are actually measured, we present the region in the {kappa}-{lambda} plane to which the W couplings can be restricted with a given confidence level. We find that combining the three processes, one can measure {kappa} and {lambda} with accuracy of 0.01--0.02.

Research Organization:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Organization:
USDOE; USDOE, Washington, DC (United States)
DOE Contract Number:
AC03-76SF00515
OSTI ID:
5179194
Report Number(s):
SLAC-383; ON: DE92000888
Resource Relation:
Other Information: Thesis (Ph.D.)
Country of Publication:
United States
Language:
English