First observations of Y(1S)->gamma pi(+)pi(-) and Y(1S)->gamma pi(0)pi(0)

Authors
Anastassov, A Duboscq, JE Gan, KK Hart, T Honscheid, K Kagan, H Kass, R Lee, J Schwarthoff, H Wolf, A Zoeller, MM Richichi, SJ Severini, H Skubic, P Undrus, A Bishai, M Chen, S Fast, J Hinson, JW Menon, N Miller, DH Shibata, EI Shipsey, IPJ Glenn, S Kwon, Y Lyon, AL Roberts, S Thorndike, EH Jessop, CP Lingel, K Marsiske, H Perl, ML Savinov, V Ugolini, D Zhou, X Coan, TE Fadeyev, V Korolkov, I Maravin, Y Narsky, I Stroynowski, R Ye, J Wlodek, T Artuso, M Dambasuren, E Kopp, S Moneti, GC Mountain, R Schuh, S Skwarnicki, T Stone, S Titov, A Viehhauser, G Wang, JC Bartelt, J Csorna, SE McLean, KW Marka, S Xu, Z Godang, R Kinoshita, K Lai, IC Pomianowski, P Schrenk, S Bonvicini, G Cinabro, D Greene, R Perera, LP Zhou, GJ Chan, S Eigen, G Lipeles, E Miller, JS Schmidtler, H Shapiro, A Sun, WH Urheim, J Weinstein, AJ Wurthwein, F Jaffe, DE Masek, G Paar, HP Potter, EM Prell, S Sharma, V Asner, DM Gronberg, J Hill, TS Lange, DJ Morrison, RJ Nelson, HN Nelson, TK Roberts, D Behrens, BH Ford, WT Gritsan, A Krieg, H Roy, J Smith, JG Alexander, JP Baker, R Bebek, C Berger, BE Berkelman, K Boisvert, V Cassel, DG Crowcroft, DS Dickson, M von Dombrowski, S Drell, PS Ecklund, KM Ehrlich, R Foland, AD Gaidarev, P Galik, RS Gibbons, L Gittelman, B Gray, SW Hartill, DL Heltsley, BK Hopman, PI Kandaswamy, J Kreinick, DL Lee, T Liu, Y Mistry, NB Ng, CR Nordberg, E Ogg, M Patterson, JR Peterson, D Riley, D Soffer, A Valant-Spaight, B Warburton, A Ward, C Athanas, M Avery, P Jones, CD Lohner, M Prescott, C Rubiera, AI Yelton, J Zheng, J Brandenburg, G Briere, RA Ershov, A Gao, YS Kim, DYJ Wilson, R Yamamoto, H Browder, TE Li, Y Rodriguez, JL Sahu, SK Bergfeld, T Eisenstein, BI Ernst, J Gladding, GE Gollin, GD Hans, RM Johnson, E Karliner, I Marsh, MA Palmer, M Selen, M Thaler, JJ Edwards, KW Bellerive, A Janicek, R Patel, PM Sadoff, AJ Ammar, R Baringer, P Bean, A Besson, D Coppage, D Darling, C Davis, R Kotov, S Kravchenko, I Kwak, N Zhou, L Anderson, S Kubota, Y Lee, SJ Mahapatra, R O'Neill, JJ Poling, R Richie, T Smith, A Alam, MS Athar, SB Ling, Z Mahmood, AH Timm, S Wappler, F
Citation
A. Anastassov et al., First observations of Y(1S)->gamma pi(+)pi(-) and Y(1S)->gamma pi(0)pi(0), PHYS REV L, 82(2), 1999, pp. 286-290
Citations number
10
Categorie Soggetti
Physics
Journal title
PHYSICAL REVIEW LETTERS
ISSN journal
00319007 → ACNP
Volume
82
Issue
2
Year of publication
1999
Pages
286 - 290
Database
ISI
SICI code
0031-9007(19990111)82:2<286:FOOYPA>2.0.ZU;2-X
Abstract
We report on a study of exclusive radiative decays of the Y(1S) resonance c ollected with the CLEO II detector operating at the Cornell Electron Storag e Ring. We present the first observation of the radiative decays Y(1S) --> gamma pi(+)pi(-) and Y(1S) --> gamma pi(0)pi(0). For the dipion mass regime m(pi pi) > 1.0 GeV, we obtain N(Y(1S) --> gamma pi(+)pi(-)) = (6.3 +/- 1.2 +/- 1.3) x 10(-5) and B(Y(1S) --> gamma pi(0)pi(0)) = (1.7 +/- 0.6 +/- 0.3 ) x 10(-5).