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Title: Hard photon processes in electron-positron annihilation at 29 GeV

Abstract

The hard photon processes ..mu mu gamma.. and hadrons + ..gamma.. in e/sup +/e/sup -/ annihilation at 29 GeV have been studied. The study is based on an integrated luminosity of 226 pb/sup -1/ taken at PEP with the Mark II detector. For the ..mu mu gamma.. process, a small fraction of non-planar events are observed with missing momentum along the beam direction. The resulting missing energy spectrum is consistent with that expected from higher order effects. The observed cross section is consistent with the predicted cross section for this process, sigma/sup exp/sigma/sup th/ = .90 +- .05 +- .06. The observed hard photon energy spectrum and mass distributions are found to be in agreement with O(..cap alpha../sup 3/) QED. The measured charge asymmetry is in good agreement with the predicted value, A/sub exp/A/sub th/ = .83 +- .25 +- .12. The ..mu gamma.. invariant mass distribution is used to place a limit on a possible excited muon coupling G..gamma../M* for excited muon masses in the range 1 < M* < 21 GeV of (G..gamma../M*)/sup 2/ < 10/sup -5/ GeV/sup -2/ at a 95% confidence level. In the hadrons + ..gamma.. process, evidence for final state radiation is found inmore » an excess of events over that predicted from initial state radiation alone of 253 +- 54 +- 60 events. Further evidence for final state radiation is found in a large hadronic charge asymmetry A/sub Had+..gamma../= (-24.6 +- 5.5)%.« less

Authors:
Publication Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
OSTI Identifier:
7059641
Report Number(s):
LBL-22433
ON: DE87006248
DOE Contract Number:  
AC03-76SF00098
Resource Type:
Technical Report
Resource Relation:
Other Information: Thesis. Portions of this document are illegible in microfiche products
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ELECTRON-POSITRON INTERACTIONS; ANNIHILATION; ASYMMETRY; FINAL-STATE INTERACTIONS; GEV RANGE 10-100; HADRONS; MUONS; PEP STORAGE RINGS; PHOTONS; QUANTUM ELECTRODYNAMICS; REST MASS; BASIC INTERACTIONS; ELECTRODYNAMICS; ELECTROMAGNETIC INTERACTIONS; ELEMENTARY PARTICLES; ENERGY RANGE; FERMIONS; FIELD THEORIES; GEV RANGE; INTERACTIONS; LEPTON-LEPTON INTERACTIONS; LEPTONS; MASS; MASSLESS PARTICLES; PARTICLE INTERACTIONS; QUANTUM FIELD THEORY; STORAGE RINGS; 645101* - High Energy Physics- Particle Interactions & Properties-Experimental- Electromagnetic Interactions & Properties

Citation Formats

Gold, M S. Hard photon processes in electron-positron annihilation at 29 GeV. United States: N. p., 1986. Web. doi:10.2172/7059641.
Gold, M S. Hard photon processes in electron-positron annihilation at 29 GeV. United States. https://doi.org/10.2172/7059641
Gold, M S. 1986. "Hard photon processes in electron-positron annihilation at 29 GeV". United States. https://doi.org/10.2172/7059641. https://www.osti.gov/servlets/purl/7059641.
@article{osti_7059641,
title = {Hard photon processes in electron-positron annihilation at 29 GeV},
author = {Gold, M S},
abstractNote = {The hard photon processes ..mu mu gamma.. and hadrons + ..gamma.. in e/sup +/e/sup -/ annihilation at 29 GeV have been studied. The study is based on an integrated luminosity of 226 pb/sup -1/ taken at PEP with the Mark II detector. For the ..mu mu gamma.. process, a small fraction of non-planar events are observed with missing momentum along the beam direction. The resulting missing energy spectrum is consistent with that expected from higher order effects. The observed cross section is consistent with the predicted cross section for this process, sigma/sup exp/sigma/sup th/ = .90 +- .05 +- .06. The observed hard photon energy spectrum and mass distributions are found to be in agreement with O(..cap alpha../sup 3/) QED. The measured charge asymmetry is in good agreement with the predicted value, A/sub exp/A/sub th/ = .83 +- .25 +- .12. The ..mu gamma.. invariant mass distribution is used to place a limit on a possible excited muon coupling G..gamma../M* for excited muon masses in the range 1 < M* < 21 GeV of (G..gamma../M*)/sup 2/ < 10/sup -5/ GeV/sup -2/ at a 95% confidence level. In the hadrons + ..gamma.. process, evidence for final state radiation is found in an excess of events over that predicted from initial state radiation alone of 253 +- 54 +- 60 events. Further evidence for final state radiation is found in a large hadronic charge asymmetry A/sub Had+..gamma../= (-24.6 +- 5.5)%.},
doi = {10.2172/7059641},
url = {https://www.osti.gov/biblio/7059641}, journal = {},
number = ,
volume = ,
place = {United States},
year = {Sat Nov 01 00:00:00 EST 1986},
month = {Sat Nov 01 00:00:00 EST 1986}
}