We study charmonium resonances produced via two-photon interactions and decaying to the K0S K+ PI- and K+ K- PI+ PI- PI0 final states, using data collected by the BaBar experiment, located at the PEP-II asymmetric e+e- storage ring at SLAC National Accelerator Laboratory. We observe the eta_c(1S), chi_c0(1P) and eta_c(2S) resonances produced in two-photon interactions and decaying to K+ K- PI+ PI- PI0, with significances of 18.1, 5.4 and 5.3 standard deviations (including systematic errors), respectively, and report 4.0sigma evidence of the chi_c2(1P) decay to this final state. We measure the eta_c(2S)mass and width in K0S K+ PI- decays, and obtain the values m(eta_c(2S))= 3638.5 +/- 1.5 +/- 0.8 MeV/c^2 and Gamma(eta_c(2S)) = 13.4 +/- 4.6 +/- 3.2 MeV, where the first uncertainty is statistical and the second is systematic. We measure the two-photon width times branching fraction for the reported resonance signals, and search for the chi_c2(2P) resonance, but no significant signal is observed.

STUDY OF CHARMONIUM RESONANCES IN THE GAMGAM -> K0S K+PI- AND GAMGAM -> K+K-PI+PI-PI0 PROCESSES

BIASSONI, PIETRO
2012

Abstract

We study charmonium resonances produced via two-photon interactions and decaying to the K0S K+ PI- and K+ K- PI+ PI- PI0 final states, using data collected by the BaBar experiment, located at the PEP-II asymmetric e+e- storage ring at SLAC National Accelerator Laboratory. We observe the eta_c(1S), chi_c0(1P) and eta_c(2S) resonances produced in two-photon interactions and decaying to K+ K- PI+ PI- PI0, with significances of 18.1, 5.4 and 5.3 standard deviations (including systematic errors), respectively, and report 4.0sigma evidence of the chi_c2(1P) decay to this final state. We measure the eta_c(2S)mass and width in K0S K+ PI- decays, and obtain the values m(eta_c(2S))= 3638.5 +/- 1.5 +/- 0.8 MeV/c^2 and Gamma(eta_c(2S)) = 13.4 +/- 4.6 +/- 3.2 MeV, where the first uncertainty is statistical and the second is systematic. We measure the two-photon width times branching fraction for the reported resonance signals, and search for the chi_c2(2P) resonance, but no significant signal is observed.
17-feb-2012
Inglese
charmonium ; two-photon collisions ; BaBar
PALOMBO, FERNANDO
BERSANELLI, MARCO RINALDO FEDELE
Università degli Studi di Milano
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/20.500.14242/171028
Il codice NBN di questa tesi è URN:NBN:IT:UNIMI-171028