The χb1(3P) and χb2(3P) states are observed through their (3S)γ decays, using an event sample of proton-proton collisions collected by the CMS experiment at the CERN LHC. The data were collected at a center-of-mass energy of 13 TeV and correspond to an integrated luminosity of 80.0 fb-1. The (3S) mesons are identified through their dimuon decay channel, while the low-energy photons are detected after converting to e+e- pairs in the silicon tracker, leading to a χb(3P) mass resolution of 2.2 MeV. This is the first time that the J=1 and 2 states are well resolved and their masses individually measured: 10513.42±0.41(stat)±0.18(syst) MeV and 10524.02±0.57(stat)±0.18(syst) MeV; they are determined with respect to the world-average value of the ~(3S) mass, which has an uncertainty of 0.5 MeV. The mass splitting is measured to be 10.60±0.64(stat)±0.17(syst) MeV.

Observation of the χb1 (3P) and χb2 (3P) and Measurement of their Masses / Sirunyan, A.M., Tumasyan, A., Adam, W., Ambrogi, F., Asilar, E., Bergauer, T., Brandstetter, J., Dragicevic, M., Ero, J., Escalante Del Valle, A., Flechl, M., Fruhwirth, R., Ghete, V.M., Hrubec, J., Jeitler, M., Krammer, N., Kratschmer, I., Liko, D., Madlener, T., Mikulec, I., et al.. - In: PHYSICAL REVIEW LETTERS. - ISSN 0031-9007. - 121:9(2018), p. 092002. [10.1103/PhysRevLett.121.092002]

Observation of the χb1 (3P) and χb2 (3P) and Measurement of their Masses

Cipriani M.;Del Re D.;Longo E.;Organtini G.;Paramatti R.;Rahatlou S.;Santanastasio F.;
2018

Abstract

The χb1(3P) and χb2(3P) states are observed through their (3S)γ decays, using an event sample of proton-proton collisions collected by the CMS experiment at the CERN LHC. The data were collected at a center-of-mass energy of 13 TeV and correspond to an integrated luminosity of 80.0 fb-1. The (3S) mesons are identified through their dimuon decay channel, while the low-energy photons are detected after converting to e+e- pairs in the silicon tracker, leading to a χb(3P) mass resolution of 2.2 MeV. This is the first time that the J=1 and 2 states are well resolved and their masses individually measured: 10513.42±0.41(stat)±0.18(syst) MeV and 10524.02±0.57(stat)±0.18(syst) MeV; they are determined with respect to the world-average value of the ~(3S) mass, which has an uncertainty of 0.5 MeV. The mass splitting is measured to be 10.60±0.64(stat)±0.17(syst) MeV.
2018
hadron-hadron scattering (experiments); hadron spectroscopy; qcd; cms; lhc
01 Pubblicazione su rivista::01a Articolo in rivista
Observation of the χb1 (3P) and χb2 (3P) and Measurement of their Masses / Sirunyan, A.M., Tumasyan, A., Adam, W., Ambrogi, F., Asilar, E., Bergauer, T., Brandstetter, J., Dragicevic, M., Ero, J., Escalante Del Valle, A., Flechl, M., Fruhwirth, R., Ghete, V.M., Hrubec, J., Jeitler, M., Krammer, N., Kratschmer, I., Liko, D., Madlener, T., Mikulec, I., et al.. - In: PHYSICAL REVIEW LETTERS. - ISSN 0031-9007. - 121:9(2018), p. 092002. [10.1103/PhysRevLett.121.092002]
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11573/1354183
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