Measurement of the ${e}^{+}{e}^{{-}}{\rightarrow}{{\pi}}^{+}{{\pi}}^{{-}}{{\pi}}^{0}{{\pi}}^{0}$ cross section using initial-state radiation at BABAR

J.P. Lees (1) , V. Poireau (1) , V. Tisserand (1) , E. Grauges , A. Palano , G. Eigen , David Nathan Brown , Yu.G. Kolomensky , M. Fritsch , H. Koch , T. Schroeder , C. Hearty , T.S. Mattison , J.A. Mckenna , R.Y. So , V.E. Blinov , A.R. Buzykaev , V.P. Druzhinin , V.B. Golubev , E.A. Kravchenko , A.P. Onuchin , S.I. Serednyakov , Yu.I. Skovpen , E.P. Solodov , K.Yu. Todyshev , A.J. Lankford , J.W. Gary , O. Long , A.M. Eisner , W.S. Lockman , W. Panduro Vazquez , D.S. Chao , C.H. Cheng , B. Echenard , K.T. Flood , D.G. Hitlin , J. Kim , T.S. Miyashita , P. Ongmongkolkul , F.C. Porter , M. Röhrken , Z. Huard , B.T. Meadows , B.G. Pushpawela , M.D. Sokoloff , L. Sun , J.G. Smith , S.R. Wagner , D. Bernard (2) , M. Verderi (2) , D. Bettoni , C. Bozzi , R. Calabrese , G. Cibinetto , E. Fioravanti , I. Garzia , E. Luppi , V. Santoro , A. Calcaterra , R. de Sangro , G. Finocchiaro , S. Martellotti , P. Patteri , I.M. Peruzzi , M. Piccolo , M. Rotondo , A. Zallo , S. Passaggio , C. Patrignani , H.M. Lacker , B. Bhuyan , U. Mallik , C. Chen , J. Cochran , S. Prell , H. Ahmed , A.V. Gritsan , N. Arnaud (3) , M. Davier (3) , F. Le Diberder (3) , A.M. Lutz (3) , G. Wormser (3) , D.J. Lange , D.M. Wright , J.P. Coleman , D.E. Hutchcroft , D.J. Payne , C. Touramanis , A.J. Bevan , F. Di Lodovico , R. Sacco , G. Cowan , Sw. Banerjee , David Norvil Brown , C.L. Davis , A.G. Denig , W. Gradl , K. Griessinger , A. Hafner , K.R. Schubert , R.J. Barlow , G.D. Lafferty , R. Cenci , A. Jawahery , D.A. Roberts , R. Cowan , S.H. Robertson , B. Dey , N. Neri , F. Palombo , R. Cheaib , L. Cremaldi , R. Godang , D.J. Summers , P. Taras , G. De Nardo , C. Sciacca , G. Raven , C.P. Jessop , J.M. Losecco , K. Honscheid , R. Kass , A. Gaz , M. Margoni , M. Posocco , G. Simi , F. Simonetto , R. Stroili , S. Akar (4) , E. Ben-Haim (4) , M. Bomben (4) , G.R. Bonneaud (4) , G. Calderini (4) , J. Chauveau (4) , G. Marchiori (4) , J. Ocariz (4) , M. Biasini , E. Manoni , A. Rossi , G. Batignani , S. Bettarini , M. Carpinelli , G. Casarosa , M. Chrzaszcz , F. Forti , M.A. Giorgi , A. Lusiani , B. Oberhof , E. Paoloni , M. Rama , G. Rizzo , J.J. Walsh , A.J.S. Smith , F. Anulli , R. Faccini , F. Ferrarotto , F. Ferroni , A. Pilloni , C. Bünger , S. Dittrich , O. Grünberg , M. Heß , T. Leddig , C. Voß , R. Waldi , T. Adye , F.F. Wilson , S. Emery (5) , G. Vasseur (5) , D. Aston , C. Cartaro , M.R. Convery , J. Dorfan , W. Dunwoodie , M. Ebert , R.C. Field , B.G. Fulsom , M.T. Graham , C. Hast , W.R. Innes , P. Kim , D.W.G.S. Leith , S. Luitz , D.B. Macfarlane , D.R. Muller , H. Neal , B.N. Ratcliff , A. Roodman , M.K. Sullivan , J. Va'Vra , W.J. Wisniewski , M.V. Purohit , J.R. Wilson , A. Randle-Conde , S.J. Sekula , M. Bellis , P.R. Burchat , E.M.T. Puccio , M.S. Alam , J.A. Ernst , R. Gorodeisky , N. Guttman , D.R. Peimer , A. Soffer , S.M. Spanier , J.L. Ritchie , R.F. Schwitters , J.M. Izen , X.C. Lou , F. Bianchi , F. de Mori , A. Filippi , D. Gamba , L. Lanceri , L. Vitale , F. Martinez-Vidal , A. Oyanguren , J. Albert , A. Beaulieu , F.U. Bernlochner , G.J. King , R. Kowalewski , T. Lueck , I.M. Nugent , J.M. Roney , R.J. Sobie , N. Tasneem , T.J. Gershon , P.F. Harrison , T.E. Latham , R. Prepost , S.L. Wu

1 LAPP - Laboratoire d'Annecy de Physique des Particules
2 LLR - Laboratoire Leprince-Ringuet
3 LAL - Laboratoire de l'Accélérateur Linéaire
4 LPNHE (UMR_7585) - Laboratoire de Physique Nucléaire et de Hautes Énergies
5 DPhP - Département de Physique des Particules (ex SPP)

The process e+e-→π+π-2π0γ is investigated by means of the initial-state radiation technique, where a photon is emitted from the incoming electron or positron. Using 454.3  fb-1 of data collected around a center-of-mass energy of s=10.58  GeV by the BABAR experiment at SLAC, approximately 150000 signal events are obtained. The corresponding nonradiative cross section is measured with a relative uncertainty of 3.6% in the energy region around 1.5 GeV, surpassing all existing measurements in precision. Using this new result, the channel’s contribution to the leading order hadronic vacuum polarization contribution to the anomalous magnetic moment of the muon is calculated as (gμπ+π-2π0-2)/2=(17.9±0.1stat±0.6syst)×10-10 in the energy range 0.85  GeV

Mots clés: electron positron: annihilation; electron positron: colliding beams; pi: multiple production; radiation: initial-state interaction; higher-order: 0; channel cross section: measured; muon: magnetic moment: calculated; vacuum polarization: hadronic; photon: emission; fundamental constant: fine structure; narrow resonance; BaBar; SLAC PEP Stor; experimental results; electron positron --> pi+ pi- 2pi0 photon; electron positron --> omega(783) pi0; 10.58 GeV-cms

Domaines: Physique des Hautes Energies - Expérience [hep-ex]

J.P. Lees, V. Poireau, V. Tisserand, E. Grauges, A. Palano, et al.. Measurement of the ${e}^{+}{e}^{{-}}{\rightarrow}{{\pi}}^{+}{{\pi}}^{{-}}{{\pi}}^{0}{{\pi}}^{0}$ cross section using initial-state radiation at BABAR. Physical Review D, 2017, 96 (9), pp.092009. ⟨10.1103/PhysRevD.96.092009⟩. ⟨hal-01669720⟩