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Measurement of initial-state–final-state radiation interference in the processes e+eμ+μγ and e+eπ+πγ [Measurement of ISR-FSR interference in the processes e+eμ+μγ and e+eπ+πγ ]

Journal Article · · Physical Review. D, Particles, Fields, Gravitation and Cosmology
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Charge asymmetry in the processes e+e → μ+μγ and e+e → π+πγ is measured using 232 fb–1 of data collected with the BABAR detector at e+e center-of-mass energies near 10.58 GeV. An observable is introduced and shown to be very robust against detector asymmetries while keeping a large sensitivity to the physical charge asymmetry that results from the interference between initial- and final-state radiation (FSR). The asymmetry is determined as a function of the invariant mass of the final-state tracks from production threshold to a few GeV/c2. It is compared to the expectation from QED for e+e → μ+μγ, and from theoretical models for e+e → π+πγ. A clear interference pattern is observed in e+e → π+πγ, particularly in the vicinity of the f2(1270) resonance. As a result, the inferred rate of lowest-order FSR production is consistent with the QED expectation for e+e → μ+μγ, and is negligibly small for e+e → π+πγ.
Research Organization:
Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Organization:
USDOE; USDOE Office of Science (SC); USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
Contributing Organization:
The BABAR Collaboration
Grant/Contract Number:
AC02-05CH11231; AC02-76SF00515
OSTI ID:
1259207
Alternate ID(s):
OSTI ID: 1224581
OSTI ID: 1392975
Report Number(s):
SLAC-PUB--16361; arXiv:1508.04008
Journal Information:
Physical Review. D, Particles, Fields, Gravitation and Cosmology, Journal Name: Physical Review. D, Particles, Fields, Gravitation and Cosmology Journal Issue: 7 Vol. 92; ISSN PRVDAQ; ISSN 1550-7998
Publisher:
American Physical Society (APS)Copyright Statement
Country of Publication:
United States
Language:
English

References (31)

Nonresonant asymmetry in {ie305-1} journal June 1974
BHAGEN95: a Monte Carlo program for Bhabha scattering at LEP1/SLC and LEP2 energies journal May 1997
Complete QED NLO contributions to the reaction e + e − → μ + μ − γ and their implementation in the event generator PHOKHARA journal February 2014
Four pion final states with tagged photons at electron positron colliders journal January 2001
Photos — a universal Monte Carlo for QED radiative corrections in decays journal July 1991
KORALB — an upgrade to version 2.4 journal March 1995
High-energy-physics event generation with PYTHIA 5.7 and JETSET 7.4 journal August 1994
Radiative corrections to the resonant particle production journal July 1968
ππ Phase-shift analysis from 600 to 1900 MeV journal November 1973
Distributions in the process e+e− → μ+μ−(γ) journal January 1981
The precision Monte Carlo event generator for two-fermion final states in collisions journal August 2000
The BABAR detector
  • Aubert, B.; Bazan, A.; Boucham, A.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 479, Issue 1 https://doi.org/10.1016/S0168-9002(01)02012-5
journal February 2002
Measuring σ(e+e−→hadrons) using tagged photons journal July 1999
Time-integrated luminosity recorded by the BABARdetector at the PEP-IIe+e- collider
  • Lees, J. P.; Poireau, V.; Tisserand, V.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 726 https://doi.org/10.1016/j.nima.2013.04.029
journal October 2013
The BaBar detector: Upgrades, operation and performance
  • Aubert, B.; Barate, R.; Boutigny, D.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 729 https://doi.org/10.1016/j.nima.2013.05.107
journal November 2013
Charge asymmetry and radiative ϕ decays journal March 2005
Large angle QED processes at e + e colliders at energies below 3 GeV journal October 1997
Radiative corrections for pion and kaon production at e + e colliders of energies below 2 GeV journal October 1997
Hadronic cross sections in electron-positron annihilation with tagged photon journal December 1998
Exclusive production of pion pairs in γ*γ collisions at large Q2 journal September 2000
Pion pair production in e + e − annihilation journal May 2006
Erratum: Pion pair production in e + e − annihilation [Phys. Rev. D 73 , 094021 (2006)] journal May 2007
Review of Particle Physics journal July 2012
Precise measurement of the e + e − → π + π − ( γ ) cross section with the initial-state radiation method at BABAR journal August 2012
Precise Measurement of the e + e − → π + π − ( γ ) Cross Section with the Initial State Radiation Method at BABAR journal December 2009
Precision Measurements of the Timelike Electromagnetic Form Factors of Pion, Kaon, and Proton journal December 2005
The Physics of the B Factories journal November 2014
Confronting spectral functions from ee annihilation and $\tau$ decays: consequences for the muon magnetic moment journal April 2003
Nucleon form factors, B-meson factories and the radiative return journal July 2004
Radiative return at $\Phi$ - and B-factories: FSR for muon pair production at next-to-leading order journal February 2005
Spectroscopy at B-Factories Using hard Photon Emission journal December 1999

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