Higher-order multipole amplitudes in charmonium radiative transitions
| Autor: | Artuso, M, Blusk, S, Khalil, S, Mountain, R, Randrianarivony, K, Skwarnicki, T, Stone, S, Wang, JC, Zhang, LM, Bonvicini, G, Cinabro, D, Lincoln, A, Smith, MJ, Zhou, P, Zhu, J, Naik, P, Rademacker, J, Asner, DM, Edwards, KW, Reed, J, Robichaud, AN, Tatishvili, G, White, EJ, Briere, RA, Vogel, H, Onyisi, PUE, Rosner, JL, Alexander, JP, Cassel, DG, Ehrlich, R, Fields, L, Galik, RS, Gibbons, L, Gray, SW, Hartill, DL, Heltsley, BK, Hunt, JM, Kreinick, DL, Kuznetsov, VE, Ledoux, J, Mahlke-Krueger, H, Patterson, JR, Peterson, D, Riley, D, Ryd, A, Sadoff, AJ, Shi, X, Stroiney, S, Sun, WM, Yelton, J, Rubin, P, Lowrey, N, Mehrabyan, S, Selen, M, Wiss, J, Kornicer, M, Mitchell, RE, Shepherd, MR, Tarbert, CM, Besson, D, Pedlar, TK, Xavier, J, Cronin-Hennessy, D, Gao, KY, Hietala, J, Poling, R, Zweber, P, Dobbs, S, Metreveli, Z, Seth, KK, Tan, BJY, Tomaradze, A, Brisbane, S, Libby, J, Martin, L, Powell, A, Spradlin, P, Thomas, C, Wilkinson, G, Mendez, H, Ge, JY, Miller, DH, Shipsey, IPJ, Xin, B, Adams, GS, Hu, D, Moziak, B, Napolitano, J, Ecklund, KM, Insler, J, Muramatsu, H, Park, CS, Thorndike, EH, Yang, F, Collaboration, CLEO |
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| Jazyk: | angličtina |
| Rok vydání: | 2009 |
| Předmět: |
Physics
Nuclear and High Energy Physics Particle physics 010308 nuclear & particles physics Electron–positron annihilation Maximum likelihood Order (ring theory) FOS: Physical sciences 01 natural sciences 3. Good health High Energy Physics - Experiment Combinatorics Particle decay High Energy Physics - Experiment (hep-ex) Amplitude Angular distribution 0103 physical sciences High Energy Physics::Experiment 010306 general physics Multipole expansion |
| Zdroj: | PHYSICAL REVIEW D. 80(11) |
| ISSN: | 1550-2368 1550-7998 |
| Popis: | Using 24 million $\psi' \equiv \psi(2S)$ decays in CLEO-c, we have searched for higher multipole admixtures in electric-dipole-dominated radiative transitions in charmonia. We find good agreement between our data and theoretical predictions for magnetic quadrupole (M2) amplitudes in the transitions $\psi' \to \gamma \chi_{c1,2}$ and $\chi_{c1,2} \to \gamma J/\psi$, in striking contrast to some previous measurements. Let $b_2^J$ and $a_2^J$ denote the normalized M2 amplitudes in the respective aforementioned decays, where the superscript $J$ refers to the angular momentum of the $\chi_{cJ}$. By performing unbinned maximum likelihood fits to full five-parameter angular distributions, we determine the ratios $a_2^{J=1}/a_2^{J=2} = 0.67^{+0.19}_{-0.13}$ and $a_2^{J=1}/b_2^{J=1} = -2.27^{+0.57}_{-0.99}$, where the theoretical predictions are independent of the charmed quark magnetic moment and are $a_2^{J=1}/a_2^{J=2} = 0.676 \pm 0.071$ and $a_2^{J=1}/b_2^{J=1} = -2.27 \pm 0.16$. Comment: 32 pages, 7 figures, acceptance update |
| Databáze: | OpenAIRE |
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